Tom Tobin: yeah I think we're good to go.
Man Lu: Okay, well, we go.
Man Lu: into the.
Man Lu: Actual Mr man on the right footing, and it was like good in parallel look like I don't sound like.
Man Lu: me.
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Man Lu: You must have an Obama.
Man Lu: The posters.
Man Lu: Up sounds like.
Man Lu: let's get started.
Man Lu: Okay, after everyone, my name is mango and post on working at the University of Alabama time off my puppet is crazy world quite frankly say initiated by Murray organic haven't barrier as a freemium to premium function.
Man Lu: What choir is one of the nature's most dramatic precisely and it has a purpose as a concept.
Man Lu: They can change the right patient structure and communicate, they can also alter the soil and water chemistry.
Man Lu: or two major indicators for what prior first one is chuckles so on these slides the LIFE photo show how the mold and chaka look like and that's a prototype of the incomplete combustion of.
Man Lu: And then from this photo you can find their fibrous like an open MIC here we are showing you the cellular structure.
Man Lu: And when you observe the Chapel under the microscope called them, as you know, the nights and this photo show how the you know the night.
Man Lu: Like under them reflect a microscope the here, we have some great holiday here we're shall we should night as a remains of the vascular plants.
Man Lu: And you can also find some brighter color them with here, we are here at the you know, Nice and the you know the Nice you perform compared to unburden what your career how high reflectance and our secular actually fragments.
Man Lu: that's a important indicator for wealth wire is preventing pH.
Man Lu: pH are organic compounds released by Bernie and they have been widely accepted as effective know chemical markers acquire active on the geological time scale on this slide I show three pack call project page compounds and the my study I also use them as he.
Man Lu: saw how the wealth, while he was doing the devonian and this fever some wise of global wildfire crisis from the signaling to the left for me.
Man Lu: And stupider all this evidence for fire was observed from the latest research they doing rocks and from this bigger and the occurrences remain low from the Arctic devonian don't the middle.
Man Lu: And then we look at the labels will mean we can find that there is wrapped wise in fire currencies from the Left wrong in order for me, however, so far that only several status reporting continuous temperature change in.
Man Lu: Our frequency during the maintenance.
Man Lu: So you might call today i'm getting into q3 on previous studies, the first one is dreamer published in 2015 my or the United maestro from the black shells are in Kentucky and Ohio State, and this sections a contender for me.
Man Lu: And the from this fever, you have fun today of increasing what not enough abundance days, so the communion.
Man Lu: The next time they is Lou published in 2020 they might know that you know not much from from the actual the five five offices in New York state.
Man Lu: And in this finger the black dots represent during dinner tonight data and they absorb higher abundances of again not in it for me in for the frog in water, you know i've only heard from several samples from the pmc call and you can't find it have positive is crucial, as I found.
Man Lu: My study is Cairo and others population in 2013 they have stagnated you the project page as fire paper and they might have them from the black shirts and lunch in Belgium.
Man Lu: And the this finger, the last column is there on pH they have under they found the high concentration of power, Jan pH in the Arctic for me in fiber this data has been questioned by others, that is due to the lack of tackle.
Man Lu: Some of these three previous studies, first, but you have fun with the items from the black shells and limestone.
Man Lu: On this link they won't even pay your geographic Mike for the staffing sections here under the copper color represent the shadow mine your island and you have fun all the study sections what updated Inshallah.
Man Lu: So just keep that the occurrences of hustle travels and he worried rocks and continuous riker of wildfire based on day three studies can find that continuous high resolution time for change or wildfire prophecy across Africa quandary to do need to be domesticated.
Man Lu: So you must study i'm going to answer to research questions, the first one is hoggy the wealth by wall across Africa on second is what cause i'm Boucher of our fire across if I.
Man Lu: wasn't, the first question, for what the hypotheses at there was a rise of wildfire for office, the crows if i'm on and for the second question, we have for the side that changes from is related to can happen barrier and affinity.
Man Lu: So to test my first hypothesis be collecting samples from Upper devonian channel Shell from central Tennessee.
Man Lu: And from this live a long period of geographic map and find the Channel show you this section was also updated shalimar environment and this photo is i'm sure how my study section look like the client is a whole race of the Channel will show you that the section.
Man Lu: The location of boundary in this section once they come in the my paper published on us and the exact study with project that the if I found the ratio of her about.
Man Lu: Her about the base of the triangle shoe proclivities based on the folly of this.
Man Lu: Is fabulous I found pottery link is wrong and content.
Man Lu: and understand, they also recalled a crisis of latest thronging condom go, which is i'm inserting.
Man Lu: The winning this Ms 13 don't we have everything we are kind of actually reaching Center here what can he which was sort of her right pillows I found.
Man Lu: Another important evidence is where Mayra the cabin surfing value prop they observe a part of a discussion here this part of a person has been observed over the world around.
Man Lu: But based on this evidence, we put our location of the iPhone.
Man Lu: In this study with climate is certainly samples at 20,000 unbeatable in mobile crop and then we collected certainly five samples right below the iPhone.
Man Lu: And then we did the organic material chemical analysis on first way these are getting.
Man Lu: All the samples or choco analysis and then we also contact is about macro analysis.
Man Lu: This is my personal choco result and this photo show valve my sample look like under my I think my.
Man Lu: scope and you have fun some Greek Helen what here we are, which are which night, you can also find some brighter color what here we are, we shine you know.
Man Lu: We count them on my phone call and then packers a ratio between the year or the ratio has been used to reply to fire from the from this feeling of funds mutual swimming consistent throw the frog in after the afa Andre to showing current trends.
Man Lu: And you must study, so this is my pH they have, and this is about macro macro gram of I love my samples and so right paler highlight the progenitor pH.
Man Lu: In my concentrations of thumb and then calculate the ratio between the power Daddy he published 27 no mountain cabin $27 outcome with soap derived from the fans and the original because i'm has been are used refiners fire from.
Man Lu: The from this theory of funds to produce women consistently lower throw the frog interval the after the film, you need to have fundraisers showing increasing trend.
Man Lu: Of the significant positive correlation between nine you know, the ratio and a pH ratio so both of them show the increased by Friday afternoon, if I.
Man Lu: know you must add a hypothesize that he has organic carbon barrier cost of fire frank's a change, I by Andre is known for the global scale reputation of my organic crisis.
Man Lu: On this laid on this data volume pillow geographic my August us up like that represent the occurrences of organic might share and limestone around five boundary so you can find that day there was updated report, as I time.
Man Lu: of organic carbon can generate long build up while most and she can't create a focus of fire at that time.
Man Lu: to quantify the amount of carbon barrier I in this study we use our forward box model for the globe, of having cycle and this model would propose is on this too sad patients.
Man Lu: As the left side of the patient I I represent, have a Max for the marine rise up.
Man Lu: And the day comprising and they comprise the cabin flux, they were from the continental widening the, what can the innovation.
Man Lu: And the third eye here at present their carbon isotope compensation left side of the ocean, the right side of the to represent up carbon flat an FC right present the file cabinets carbon right reasons, if I have any part of the Thursday under the referees and there is a compensation.
Man Lu: Here we will find there is a bias twins I put comments last and up.
Man Lu: And there is a compensation which are status.
Man Lu: and based on this basic patients have other propose a time dependent equation, and my style, they will use this equation to calculate for which is equal to the organic carbon bond your rate.
Man Lu: We have our writing though the values today's climate, and this is a quote from the previous studies and the indices mission and use a lot.
Man Lu: Of highlights a parameter, we should suffice from the previous from other studies first time in his wishes have been searching for cabin certain why they have cabinet.
Man Lu: And the size of I do from available status of either leave the building and rocks and as a life outside of a, we also need to determine the time to be assigned age to each covenant eyes.
Man Lu: I suppose the ages are calculated by using the veil geographic donation given by the other advice absolutely the ages given by the powers of Congress.
Man Lu: After we go them, how do we calculate the organic carbon barrier rate and on this slide to white line is a trend line and just focus on the leap frog in the fall and then you have find out why newsroom in Florida other.
Man Lu: The here I use orange line to highlight, if you have fun approaching the i'm wondering why do we place an Irish the highest value.
Man Lu: So just keep that in the organic carbon barrier is if I so combine it with by are worthwhile, they have a record it just organic carbon Barrio as if I boundary the English is a rise of the office during the communion.
Man Lu: So you might say, can hypothesis, we propose that we hypothesize that organic carbon earlier on, is related to the welfare changes, so how it can change the wildfire from the.
Man Lu: First, they can change as much oxygen level and the oxygen can be removed from the atmos during the respiration and that they have the organic carbon.
Man Lu: So you can use organic haven't Barbara with a quiz on hulu hulu will liberate more oxygen at most and the further increase i'm frank was.
Man Lu: This finger some why the modeling results are showing how the oxygen level change both of us history and there's a paper here highlighted label your inbox and we can fill your agreement with our result because fun, all the studies showing increasing trend with you in the lake.
Man Lu: Saxon late on so you have organic carbon barrier can have direct influence on the climate change and the my study I use this process.
Man Lu: to fly the climate change first one is chemical effects of occupation, the second one is about my vision for why we have so just on fighting climate.
Man Lu: And from this theoretical fun afters if I found also have them show the door decreasing trend, though, the Philippines, so just picking up on climate.
Man Lu: Climate and.
Man Lu: So on so we suggest that I see this can come and barrier where they create a CO2 concentration at the most, it will lower the temperature.
Man Lu: which were other cooling climate where produce life and what are we are in that mode, which will be our products are trying climate and then further increase the frequency of.
Man Lu: So the punk lawyers of my star, the first what choir pharmacy your priest after that I found on.
Man Lu: Fire for atlas it is linked to the organic carbon area as the iPhone.
Man Lu: is writing organic carbon borrow money to hire and most most reliable and dryer climate during the minion pulls off may have he may have.
Man Lu: So here i'm going to thank the support from these findings, and I welcome any questions.
Man Lu: So I think I still have a couple minutes.
Man Lu: Three minutes.
Tom Tobin: Do we have any questions, people can raise their hand or just turn on their.
Tom Tobin: Video and ask question if they want or you can ask a question, via the chat.
Man Lu: On.
Tom Tobin: I can ask you a quick question man that when people are figuring things out.
Tom Tobin: The more oxygen things he's pretty well linked with forest fires, but my understanding is that most conditions.
Tom Tobin: A lower temperature would be associated with a lower risk of wildfires all other things being equal, if you put much thought into looking at other time periods with lower temperatures.
Man Lu: So for my study I didn't guys.
Man Lu: think you guys have proxy for the temperature change, based on the other studies, there is a calling parents and latest for me.
Man Lu: which was a blessing virtualization a look hi the.
Man Lu: temperature the temperature is still pretty high i'd like hi Oh, they only think Chris critically during the latest me.
Man Lu: um.
Man Lu: No more question, I think we can move to our next speaker, which is in China.
Tom Tobin: You should probably wait and started on the 50 mark just because to keep ourselves on schedule, people are jumping around from session to session.
Man Lu: Okay yeah.
Just because.
Tom Tobin: that's my feeling on this subject, but i'm happy to.
Tom Tobin: Do differently, we want.
Tom Tobin: Do you want to get your screen sharing going and things like that, though, we can get that rolling.
Jian Chen: see my screen.
Tom Tobin: Can you, I want to make it full screen on the presentation, but.
Tom Tobin: Give it one more minute.
Tom Tobin: hello, are you doing interest.
Man Lu: yeah i'm still on our let's welcome our next speaker.
Man Lu: From your voice of Alabama.
Man Lu: Is the title of our talk is micro Community response to the point where i'm going home.
Man Lu: alright.
Man Lu: guys welcome.
Jian Chen: Thank you for your introduction and welcome to my presentation.
Jian Chen: My research is about microbial Community response to OSHA Annika anoxic events so after that, the only metric conditions as a hypothesis of global cooling.
Jian Chen: Hello cooling oceanic acid occasion for Kenny his own and and Maria Nancy are is all are often proposed, our thoughts are live at the bone mass extinction events.
Jian Chen: At the Marina nexia is a while also most popular opposed to support our live with the owner mass extinctions because many studies that have new builders.
Jian Chen: association all of my real enough crb late at the mass extinctions like studies suggest relationship between your senior and too late at the volumetric financial studies indicate that relationship between an oxy and FM mass extinction in Europe and Australia some studies.
Jian Chen: reveal the anoxic or you have not doing an elitist our feminine power broker event in the South China.
Jian Chen: He stated that manager chemical proxies also revealed itself association all related to only appear arguments, but he's a marine anoxic environments.
Jian Chen: are left with the comments 13 of companies and organic carbon suggest a toxic environment having a doing the upper and a lower work how rest, are you are you.
Jian Chen: Are markers can help us.
Jian Chen: An oxy cotton environments have, in the form of our teams are your events event and the trees medal in I can kill as an oxy for humans happened that into a horrible good balance sheet metal data data often also can show us similar story about it.
Jian Chen: On oxygen environments and from the funnier to feminine.
Jian Chen: anoxic environments, it can cause more ecosystem class, but at the same time Murray, where we microbial.
Jian Chen: microbial communities have some very interesting response to the toxic environments many studies.
Jian Chen: How discover the changes in microbial communities are doing different them as it country bands like is our perimeter Isaac.
Jian Chen: PTT messy finishing an observation as attention, but until now know people have cable asked.
Jian Chen: If we fancy will study about as a leader who anoxic EBS and responses or more microbial communities that through the anoxic how humans, so I have to research questions so first one is how many and what anoxic.
Jian Chen: o'shea anoxic or you guys have into into later the role now the second one is what are their responses, also a little the volunteer microbial community to oceanic.
Jian Chen: anoxic events in order to answer my research questions I have started my research into, you know as vision, so you know it was.
Jian Chen: In Eastern Europe, and it was advertising no savings, please.
Jian Chen: Please at the owner sediments from the Illinois basin are who the printer of the archival or what your chemistry and some sentiment orgy related to.
Jian Chen: Your mental changes and the changes in microbial communities, because of the position was a continuous and some wonderful summer maturity is a very low in the one and share.
Jian Chen: My studies side is that humans are ways to Kentucky actually it is treating hall as a core is archived in Turkey hockey geological survey.
Jian Chen: operative sediments from Illinois basin is a Shell Shell and that's the monitor Shell or license middle stellar spoken number of funds bottom to the top of the militia has six members, they are blogger sameer martinsville Cameron correct correct and Canada.
Jian Chen: So me that the only our service broker number is lemon stone.
Jian Chen: So, most of the communist top far so in this number is a black hat this Member has the week coverage intensity and initiative has a look to see data about I don't have a QC data for this number.
Jian Chen: Blocker member is a precarious black Shell fossils like Cree noise and Brett Brett has occurred in this Member not in this number this number has a little higher Tuesday and stronger camry intensity Center service order number.
Jian Chen: We killed me so Samuel member is black Shell, but we can offend some localized Dr Michelle the ratio is a centimeter scale, it is Monday.
Jian Chen: December to keep this number to say is a little bit higher and a camera intensity intensity is stronger as well.
Jian Chen: So Morgan to remember is this King to buy his load your state and a big company that has paid in this involving slow to say, we can offend a sound bath patients and standard lamanna.
Jian Chen: They indicated in your grammar into the moments should be oximeter to support and increase the lander inputs.
Jian Chen: But we also can find some black show you this number.
Jian Chen: To Cameron number has already relatively high, but a flag to eating QC we also can find some pros and send a green in this number.
Jian Chen: so clever creek Member has the highest he will say and stroke, is the memory intensity so outer the outer Shell in my studies site, the lead story in this Member is a very simple is the actual parents are very common in this number.
Jian Chen: The top stuff however man bra sizes all lowest Tuesday and with his family intensity, so the surgery in this number is green barstow we can find some intense perturbations locally in case number.
Jian Chen: I have collected at samples of funds or block remember to that and of our Members and our reach assembling interval it's about a meter.
Jian Chen: In order to reconstruct anoxic events and the changes that you made rubio communicator I have finished up for your camera your chemical analysis manager and the trees Meta analysis and analysis by different instruments.
Jian Chen: So let us see what we can't stand the results of this curve is after the concert team all organic carbon based on Saturday Constantine values and.
Jian Chen: The story of the Members are how temporarily identified or false value and so Avatar liquid ammonia myself side because the hand about Member is our costs etc boundary, so I think, as our topics and biggest.
Jian Chen: concern is corrosion is a corresponding to the hammer.
Jian Chen: To F F boundary is roughly in the camera camera remember, so I think that is why, is our cancer Vance now, this one is a corresponding to the lower commercial batch.
Jian Chen: After the middle of on your part three, there are multiple elements, they are we are straight middlesex team.
Jian Chen: can do.
Jian Chen: But at this moment i'm not sure just kind of shooting excursion is corresponding to fish, one on zoom because the best to the profit is not available, it will be easier for me to identify this one one telstra telstra the profit is available data.
Jian Chen: is not your chemical boxes of the current 13 all companies are getting the carbonate mulligan live I don't know enrichment factor uranium enrichment factor.
Jian Chen: As a ratio of sample or was a ratio of water and cover 18 to 20 arrow as open noise or normalized to accuse say I have identified to anoxic events so first one is a phones are early for nia today and also made or the second one is a form of the latest stuff for nia to.
Jian Chen: need a feminine.
Jian Chen: I also found intimidator you see screen, if you want between the two anoxic or events as a DC boundary with CAFE and.
Jian Chen: you've seen it, but you grant before this PC bottle you see Nikki banjo I can fend.
Jian Chen: off the environments or oxygenate.
Jian Chen: The value adds all X and the lbw I related to the first half anoxic or events or the UK UK w is it related to.
Jian Chen: intermittent senior and it's our 30th is always our second or Nazi for the Heidelberg usps a little bit complicated.
Jian Chen: orifice or However, the environment, was an oximeter say became opposite and the family became a percentage.
Jian Chen: Let us say the responses all microbial communities.
Jian Chen: We cash and a few others are later Florida and a famine yeah land inputs or increase them, as indicated by the ratio or launching our kinzer over workshop to outcomes and of the ratio or America or aluminum.
Jian Chen: Because it has this is doing is it's two periods of we also can find that intimidating in terminator are you feeling, even as and another you've seen it, so I think you can do intermittent senior and as a hamburger senior or related to increase the landing puts.
Jian Chen: This curve is.
Jian Chen: bacterial ready to have about this this abundance was a higher doings for anoxic events and was a low means.
Jian Chen: Not intermittent senior and the PC bottle you've seen it for us, so I think bacteria relative about the changes secular secular equally.
Jian Chen: or January follows us and you're back three, we can say either boom the forms of are you today later feminine.
Jian Chen: But it's a bonus all sound the bacteria decline since the latest stuff.
Jian Chen: about it much more topic bacteria is interesting because a the highest to to me, even as adults are doing as a little family I ended data from maybe it isn't related to the input as well.
Jian Chen: Apparently, is about our communities, we can say from the first unlocks hagar was intermittent senior so second an oxy and so PC partner you've seen, we can say to our abundance of red LG was the videos they'll pass the abundance of reality was the increase.
Jian Chen: So changing trends are for the two communities that were reversed into oxy learners, so I think that the logic and explaining QA environments for fear about to reality, but after your road to read energy.
Jian Chen: Family a hell fell conclusions so first of all, is neither colonia ocean was all the lead in oxygen in the eastern Europe, America.
Jian Chen: Why intermittent tell us senior and senior occurred in the middle of run out and ended up this a boundary respectively Atlanta imposed increase that during the UK w and Harvard and the word related foods are intermittent intermittent that you've seen it and a PC boundary cynical Iranians.
Jian Chen: Back three or four the moon cycles see on the back to school in anoxic and you've seen a few moments mass not troughs increase the during.
Jian Chen: intermission that you've seen it and, as a BC powder you've seen a car you guys anoxic or add that you've seen if the government's more favorable to.
Jian Chen: Our community, but I feel about to read our community are Finally I would like to send people have a base level analysis field workers sample collections and the sample.
Jian Chen: level Members now some of that our research found us into our scholarships.
Jian Chen: Time to kind of Christians.
Jian Chen: yeah.
Oh.
Man Lu: Go ahead.
Tom Tobin: Can I can ask you a quick question, while people are adjusting.
Tom Tobin: can hear me okay.
Tom Tobin: yeah i'm in the previous talk we thought positive excursion associated with the FF boundary that went to something like look, if I remember correctly, something in the neighborhood of negative.
Tom Tobin: And you don't see a similar much of an excursion here associated with the boundary and certainly not have the same magnitude, but we are pretty close.
Tom Tobin: and geographic proximity um do you have any thoughts on why you don't see the same record here, as he did in a relatively nearby area in the previous talk.
Jian Chen: Oh no oh yeah in the lobby that i'm the one that is, and you have your ab initio as well.
Jian Chen: In the outer Shell forms are elevating the FF roderick is in the Opera opera on your Shell so that's why I think FF boundary is here because of our democracy is a form the organ trio tucson Clara creek Member.
Tom Tobin: I guess what i'm getting at, though, is like the interpretation of these carbon isotope records, as if that represents a global shift.
Tom Tobin: i'd be curious why you don't see that global shift in your section that makes sense.
Jian Chen: I think.
Jian Chen: So global shift of order to have the ability to.
Jian Chen: resolve is it similar to others.
Jian Chen: about it that they're concerned me.
Tom Tobin: Think of a question from candy yeah.
Rindsberg, Andrew: hi i'm.
Rindsberg, Andrew: trace fossil person.
Rindsberg, Andrew: like to ask a trace fossil question Oh, the you mentioned that one of the Members, is what is quite low and burrows is there a cut off point in terms of.
Rindsberg, Andrew: oxygen or or some other parameter that you can identify that that could be useful to acknowledges.
Jian Chen: Oh, you mean.
Rindsberg, Andrew: yeah some point at which you don't see any more burrows that were the conditions are too too difficult.
Jian Chen: Oh in this Member I can find some birds patients, and those are topics I can stand for, so I think, maybe the indicator to the government's was a little bit of oxygen oxygenated.
Rindsberg, Andrew: Thank you.
Tom Tobin: good time for maybe one or two more questions if there are any.
Tom Tobin: chicken for anyone who has any questions feel free to ask him via chat.
Tom Tobin: Or to raise your hand like we just saw there.
Tom Tobin: Alright, well, we can.
Tom Tobin: kind of thank john again with us a little slow reaction since well, if you want, but who's the next you are you next.
Yuehan Lu: Year will be prison.
Tom Tobin: Sorry.
Tom Tobin: you're in bold on the thing which.
Usually.
Man Lu: means for.
Man Lu: Everyone.
Tom Tobin: yep.
Okay.
Tom Tobin: And you're good timing wise to start whenever you're ready.
John Fronimos: able to hear you are.
Tom Tobin: You speaking.
Yuehan Lu: We cannot hear you.
Man Lu: Okay.
Tom Tobin: Now we can.
Man Lu: Go no sound coming up what's going on.
Tom Tobin: We can hear you now.
Man Lu: But not from Aleppo then.
Tom Tobin: Oh, you playing recording.
Tom Tobin: yeah oh no it couldn't hear any recording so now.
Tom Tobin: If you go to when you're sharing screen I think in the top, one of the buttons is share sound and you might need to do to turn that on if you haven't.
Rindsberg, Andrew: And in the first session they recommended that we not do the share sound feature.
Rindsberg, Andrew: You might want to go to the bottom of the screen left hand, where it says mute and change select a microphone and use instead of the top one change to the second one stereo mix that should work.
Rindsberg, Andrew: But you'll have to change it back after yeah.
Tom Tobin: we're not hearing any sound UK for supposed to.
Man Lu: know.
Man Lu: No.
Tom Tobin: Just you just you talking to hear the sound from like narration or anything.
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Yuehan Lu: Fine, no, we cannot hear you.
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Tom Tobin: cool I think we're basically out of time it's been Thank you okay.
Tom Tobin: He gave us we're going to share the poster for the next talk, or do you want me to take care of that.
Man Lu: Our next speaker.
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Tom Tobin: We still still.
Man Lu: hold on.
Man Lu: Can you see the poster now.
Tom Tobin: Yes, yep.
Man Lu: Okay i'm going to play.
Tom Tobin: move don't hear the sound from it again.
Man Lu: Oh sorry.
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Tom Tobin: Let me try from my end i'll see if I can share it.
Man Lu: Okay sorry about it.
Tom Tobin: Can you all see that Okay, yes i'll try the sound hopefully it will work from the sun and we'll see.
Tom Tobin: My name is Kathleen ducky and today we able to hear that.
Man Lu: Yes, yeah cool.
Tom Tobin: All right, i'll go.
Man Lu: Talking about late devonian rocks from a new site in Southwest or Mongolia.
So the light devonian is characterized by prolonged climate instability periods oceanic and nexia and multiple mass extinctions.
The problem is our understanding of the late event Ian Ian oxiana extinction events is compromised by Paleo geographic sample bias, as nearly all study locations are in North America, Europe and South China.
North America and Europe were Paleo geographically Jason at the time as NGOs form.
On the way to the inbox shows in the US included the marcellus shale on the central appalachians and and try to new Michelle and the southern applications which are important because they hold all the available oil in that watch mountains.
The cause of the antioxidants and late, if anyone has long been debated many studies have explained these events as deep oceanic events associated with upwelling or transgression.
But a newer top down model involves land atmosphere ocean interactions that cause algal blooms in each location.
So now we're sampling devonian arcs throughout the Central Asian organic belt or the CEO be to provide a more geographically comprehensive data set and test the new top down model.
So we sampled the buying hoshi ruin section of Southwestern Mongolia which likely represents and isolated volcanic island Arc environment.
While we did not find bombshell we did find evidence of explosive volcanism volcanic ashes and salts and now we're trying to figure out the type time maturity of the island are the deposition environment how the basalt flows are related and so on.
We found meter thick ash deposits and pillow salts that are indicative of an open ocean environment.
And this environment is important because, if it is anoxic It means that the an oxy must be global and not restricted to tropical at the con and will seize.
The problem is that the anoxic here isn't presentable in a visual way due to a lack of typography that would support black Shell preservation.
So we're testing the degree of alteration to determine if tectonics and metamorphosis and had destroyed the chemical signals that will tell us whether or not we are dealing with an oxy conditions.
So far, we've used optical microscopy xperia fraction catheter luminescent and scanning electron microscopy.
And thus far they indicate that the buying COSI ruins are characterized by mixture of sedimentary rock volcanic rocks and volcanic classic rocks that have experienced low grade my Marxism up through print it familiar faces.
And if you look at these images of the one on the top left is optical microscopy image showing evidence and some logo a metamorphosis as well as the bottom left, which is SEM also showing low grade metamorphosis on.
The top.
Right is showing cemetery rocks amateur cemetery rocks and it is capitalism in essence and the bottom right is also Catherine Catherine luminescent image showing alteration product.
Like clay or potentially see lives.
So much of this island okay Mongolia to find black shale and and ice events and said found these metamorphic sequences so i'm there for trying to decouple the amount of market mineral and chemical signatures from the original geochemical signatures.
So we found green shirt species metamorphosis and an event in Ireland, our environment.
Any anoxic signals that were originally here we're probably metamorphosed and are no longer detectable.
The metamorphosis and mineral assemblages are consistent with the tectonic setting but preclude our ability to detect the primary mineralogy and stable isotopes dangers associated with the extinction event horizons.
Although the new data collected for the site is not appropriate for determining the cause of the lead dominion extinction events, it has produced a revised strata graphic and metamorphic framework for this understudy region.
And that is all I have today Thank you so much for listening.
Tom Tobin: All right, i'm going to stop sharing and get the right way for back always just reshare that if we need to does anyone have any questions.
Tom Tobin: As soon, I think I saw Kathleen here earlier.
Katie Duckett: Yes.
Tom Tobin: So i'll ask you a question quickly.
Tom Tobin: Forgive me if you touched on this, I was trying to do some tech stuff on the bit in the background.
Tom Tobin: A simple extract some pretty some or they've been paper and people extracted organic material some pretty deformed pretty old rocks is there any chance that there's like just karajan in there, that you can get at the MIC preserve some kind of signal.
Katie Duckett: So last time we saw so so far no evidence of black show so thanks so from my knowledge, most of my research is about the.
Katie Duckett: More than mineral mineralogy to see if we can do a couple of the geo chemical signals.
Katie Duckett: So.
Katie Duckett: As knowledgeable about the black show in particular.
Tom Tobin: We have other questions either via chat or raise your hand or just.
Tom Tobin: buy them.
Tom Tobin: Just for future reference on posters I believe everyone can look at the posters online themselves so if you do we have a few more posters coming up here.
Tom Tobin: So if you want to kind of follow along and have a look around the poster as well beyond with presenters presenting feel free to do that, to go forward.
Tom Tobin: Alright, well, we don't have any other questions let's thank our speaker again and.
Tom Tobin: You can always chat with her, if you do other questions in the chat window and i'll guess for my other Co chairs i'll just queue up since i've got this queued up, I can queue up the next poster as well.
Man Lu: I know.
Tom Tobin: I can't hear what you're saying, but I assume you want me just to play the next poster.
Tom Tobin: Thanks katie.
Tom Tobin: So you give me one moment to get us queued up for the next one.
Tom Tobin: Make sure i'm queuing up the correct one.
And 40.
Tom Tobin: alright.
Tom Tobin: double check is the correct talk cool girl can see that okay.
Tom Tobin: During Paleo ecological studies larger specimens are commonly used based on their ease of collection, processing and identification.
Tom Tobin: This study aim to gather Paleo ecological insight from the often excluded smaller size fraction of fossils just want to double check that everyone's able to hear that okay.
Tom Tobin: cool Thank you.
Tom Tobin: All right, i'll resume that.
Tom Tobin: I guess i'll start that over again just so we get the title slide back in.
During Paleo ecological studies larger specimens are commonly used based on their ease of collection, processing and identification.
This study aim to gather Paleo ecological insight from the often excluded smaller size fraction of fossils.
be collected a full assemblage of large and small gastropods and analyzed both sides fractions in order to find out if the smaller gastropods different taxonomic Lee from the larger gastropods or if the smaller were immature or small adult versions of the larger kind of hurts.
We collected book Simon samples from the Pennsylvania and finance shale in West Texas at three localities within 10 kilometers of one another.
We then separated the fossils in the two sides fractions a large fraction contained fossils greater than two millimeters and the small fraction contained fossils between point eight five and two millimeters.
The small fractions were split into 420 5% sub samples corresponding to 100% large fraction for each sample all gastropods were then separated and identified to the genius level.
And here we have a comparison photo of the small versus large gastropods used in this study.
So each sample location and corresponding started graphics collection height are split into the two sides fractions shown on the X axis.
With the small fractions represented in purple and large fractions in blue, the total number of gastropods in each sample is shown on the y axis.
And at all strata graphic positions and locations in a given sample there as many as two to five times more small specimens in a single 25% split as there were in the entire large fraction.
This may be the result of preservation or a tough gnomic differences between these two sides fractions with the smaller gastropods preserved in greater numbers, then larger.
Another possibility is that the larger specimens are more susceptible to damage during sample processing, which left the smaller fraction with a higher intact number, it may also be that the Environment was just able to support greater numbers of the smaller gastropods.
We examine the relative abundance of the most abundant individual general and the color scheme here is the same with small being purple and large being blue.
The sample locations are still on the X axis and the relative abundance percentages are shown on the y axis.
service for President in both large and small fractions of the West spillway into the three strata graphic heights but they're absent completely from the highest traffic sample.
In the spillway samples small fraction serbia's were present in all three strata graphics samples, but the large Derby is for completely absent.
Similarly me go spire a smaller and larger larger fractions we're intermittently President and absent from some locations and heights.
and small fraction left or tecmo more present in all locations in depth well large fraction looked at it not more found only in two of the seven samples.
Large strap rallies were prevalent throughout all locations, with their small counterparts only in some samples.
In you from ids and Calabro singular them followed similar patterns throughout most of the samples exhibiting presence of both small and large fractions throughout most of the samples.
Again, we have the same color scheme and samples on the X axis and richness and evenness and relative abundance values are shown on the y axis.
Although there were differences in individual taxonomic relative abundances between various samples.
richness and evenness throughout all the samples are made broadly similar with the total relative abundance of all taxes, showing similar patterns, corresponding to each of the forecaster pod morphology is found within these samples.
So the smaller gastropods do not appear to be immature versions of the larger.
As the ornamentation in boyle number did not differ significantly between the two fractions indicating that the small gastropods are adults.
They appear to be miniature versions of the same taxa represented in the large fractions.
richness and even as between the two fractions both Bradley similar patterns, as did the relative abundance of the four main mythologies.
However, the small fractions plotted separately from the large fractions in ordination space suggesting ecological differences affecting tax on abundances.
So these are likely to similar but distinct communities operating at different scales within the same environment which, in turn, resulted in differing ecological patterns.
The smaller gastropods may have utilized resources differently than larger counterparts each requiring fewer resources to survive compared to the larger ones.
predators may have just preferred larger gastropods over smaller ones in both scenarios could result in higher abundances of smaller gastropods.
On the other hand, conditions during or after preservation may have resulted in more complete Community representation of the smaller factions, then in the larger factions.
And further research could investigate the possible role of tapping on me or differential preservation or damaged during processing.
Overall, based on the higher abundance of smaller specimens present in the same book samples, it may be beneficial to include these smaller individuals, alongside the larger ones in order to gain more complete understanding of the Paleo ecological community.
Tom Tobin: will stop the sharing their, hopefully, thank you very top, we have one of the speaker and one of the presenters with us.
Tom Tobin: cool awesome.
Tom Tobin: Does anyone have any questions for Austin.
John Fronimos: I have a question um so first of all thank you for the talk, I really enjoyed that.
John Fronimos: very interesting subject so you mentioned that the smaller size fraction that you are finding could be recognized as adults, rather than juveniles where they're also juveniles President small fraction or did you find that the Community seemed to only have adult gastropods President.
Austin Lloyd: So overall looking at the ornamentation and the number of worlds and growth patterns in both the small and the larger specimens they were very similar which kind of told us, but they were both more mature versus immature because they had more developed ornamentation on both types so.
John Fronimos: If you.
Tom Tobin: Remember any other questions.
Tom Tobin: asked you go, you know one he go for.
Man Lu: Your vacation on Monday and.
Tom Tobin: You can troll picking up your audio well enough there.
Tom Tobin: Are JEREMY keep chatting your question, maybe.
Tom Tobin: Meanwhile he's chatting that real quick Austin.
Tom Tobin: I don't work with gastropods a ton, but I do work with ammonites and when we work with emanates we see those, like the two sizes, we often think of like maybe sexual dwarfism is that a thing that happens in gastropods and could that be going on here.
Austin Lloyd: um i'm not sure about that that wasn't really something we looked into, we were really focusing on the structure of them and just comparing the two sides variations, but that could that might be something that we're looking at here as well.
Frank Forcino: Top top this is frank here tell that's a good question, it is possibility that we didn't really explore yet, but that absolutely could be the case.
Tom Tobin: I don't know as much know you'd look forward to confirm that but yeah there is a question in the chat which is from.
Tom Tobin: This echoes did you find a lot of fragments in the course fraction broken big shells If so, did you try to correct for that.
Austin Lloyd: So even even looking at the broken shells, there were such a higher number of smaller gastropods.
Austin Lloyd: Size fraction numbers in the one fourth split.
Austin Lloyd: Compared to the 100% large fraction of big bigger shells that we were pretty sure that that wouldn't have been a huge factor in why there's such a different amount in each section.
Tom Tobin: And we have one more question if there is one.
Tom Tobin: cool all right well let's thank our speaker again.
and
Tom Tobin: I think we have another poster coming up next.
Tom Tobin: Do you want me to just to keep rolling with the poster sharing.
Tom Tobin: And this is where we're going to transfer to you, but.
John Fronimos: sure if we've got those queued up that I think would be efficient and while you're doing that i'll quickly mentioned that.
John Fronimos: For those of you who have joined us midway through, although the official title of this session is interactions of environments in life during the paleozoic.
John Fronimos: that's meant to be fantastic, so this first set of talks have been on the paleolithic era and now we're starting to head into some talks on the mesozoic era and later we'll have some centers of excellence for you just thought you know where we're at thematically.
Tom Tobin: And will be progressing gradually through time and getting pretty much to the modern by the end of this afternoon.
Tom Tobin: I think I should be ready to share our screen.
Tom Tobin: And Richard anything.
Tom Tobin: All right, i'll assume it's going to work well for the last few work, but if it doesn't someone yell at me go from there.
alright.
Our new study presented here a colleague and I described the rich array of the Marine reptile fossil from the lake rotations of South Carolina.
Despite fossil prospect in the relevant Ross, notably the donahoe creek formation and TV formation it's quite possible prospect enrollment process since the 19th century.
Only too generic of marine reptile and i've ever been identified.
For NASA dod a title for us.
The lack of specimen probably goes back to the lack of exposures, which is a classic problem in eastern North American paleontology.
In this study we described what may well be awards collection relevant fossils mostly shed teeth in existence, unfortunately, the specimens have sub optimal but not existent locality data not non existent locality data, since they originally were found by private sector.
can't be choosy what's best for this study we rang the data for all the work.
With careful more.
analysis.
So i'll run through the.
breach.
We have labeled here at the diagnostic characteristics of support or identification.
So first up.
We have first evidence of the genius Moses, or the state level specimens like the one picture top and Center probably represent the gigantic super predator.
Which is exciting, we also have a specimen that may well represented Moses North Missouri in the tooth masters very well with what we would expect with you no imagery and says, based on the relevant literature.
But given that most or dental into specific variation and especially rp genetic variation remain fully characterized just in general across the group we opted for a more conservative, but he hits the cf.
similar situation with a to present blaine cook modalities for Python their top left excellent Marina for what we expect the species in terms of morphology but, again, we felt this was the case where occurred in the better part of valor.
Both these, though certainly are either the forms describe from the state before.
allosaurus and.
So they represent new branch and.
We also have first, please, yes or material diagnostic low or low level bottom Center some allows my story.
But they're just take your shape shape region.
And lastly.
Some other Moses doors.
liar dawn and the bottom right why it on.
A.
sort of a camaro features in this festival I kind of arrow feature seen in different species of birds will dance why it on doesn't really match any of them well.
But certainly has characteristics of the cluster of species.
Maybe it's a new species endemic to this region, but only future fun.
And finally, we have.
projects.
That are fairly normal.
For the region.
similar to the ones that have been described for quite they're quite common in this collection.
Tom Tobin: Do we have any of the presenters there are john you want to take over now.
John Fronimos: sure.
John Fronimos: So if we have any of the.
John Fronimos: presenters here we have time for some questions.
Tom Tobin: don't see.
Tom Tobin: either of them here.
Tom Tobin: Different name.
John Fronimos: either, but if you are here.
John Fronimos: Now, raise a hand.
Tom Tobin: And if not, we can take a little five minute break and resume and.
Tom Tobin: double check the timings right it.
John Fronimos: should be 3pm for the next one cool.
Tom Tobin: But to you yeah.
Tom Tobin: cool so we'll take a little five minute break then resume at 3pm for the next.
John Fronimos: hi everyone it's 3pm so we'll go ahead and move on with our session so first of all thank you for all of you who've been with us so far I hope you're.
John Fronimos: Getting a lot out of the schedule of talks that we've had so my name is john farnham most i'm going to be introducing the next few few of the talks and the first one that i'll be bringing in here is talking my own.
John Fronimos: So let's go ahead and get started with that.
John Fronimos: So hopefully you can all now see.
John Fronimos: see my slides Okay, please let me know if there's any issues seeing most.
John Fronimos: So this talk will be by myself and Daniel the part, we will be talking about airspace proportions in the pneumatic Axial and APP and peculiar skeleton of a titanosaur sauropod from the upper cretaceous of texts or shorter terms i'm going to be talking to you about some airfield dinosaurs.
John Fronimos: So, before I get into that I want to quickly acknowledge a few of my colleagues, including those at Texas tech who are involved in the collection of this material.
John Fronimos: Some colleagues at auburn university who provided some advice on the quantitative methods and some former students of mine at vassar college who contributed to the data collection.
John Fronimos: So i'm interested in the sauropod dinosaurs, as a group, for a variety of reasons, but especially because they include some of the include the largest land animals of all time among their number.
John Fronimos: So if we're interested in biomechanics and the way that the vertebrate skeleton deals with extreme stresses there's a few better groups or equal groups to look at.
John Fronimos: So if we want to understand how these animals are able to hold up so much body mass, we need to look for a special traits that might help them with this.
John Fronimos: One feature that's often been recognized as contributing to to dealing with this body mass issue is the fact that sauropod dinosaurs typically have parts of their skeleton that are filled with large aerospace This is known as pneumatic.
John Fronimos: These pneumatic chambers are connected to extensions of the lung tissue and you commonly see this within vertebrae.
John Fronimos: Particularly the neck and the DORSAL region or torso but also sometimes the tail and it can extend into the ribs the upper pelvic elements, particularly the alien and on rare occasions into the pectoral girdle as well.
John Fronimos: And so, if we can understand this new entity that we can potentially.
John Fronimos: recognize how much weight is being saved by the presence of these hollow spaces within otherwise solid bones and potentially consider other functional amplification implications of where you see the airspace and how much.
John Fronimos: So, in order to better understand this, we need to quantify urbanization the amount of air within each bone.
John Fronimos: That wasn't came up with a metric for this known as the airspace proportion, which is essentially on the.
John Fronimos: internal air volume of the bone divided by the total volume occupied by the bone, including the airspace, and so this gives us a decimal value that can be thought of is comparable to percentages.
John Fronimos: The big challenge when it comes to working with the airspace proportion in this way is that it's very difficult to measure these volumes, especially when the air spaces are fully per mineralized are filled in with sediment.
John Fronimos: And so it's much more common to use airspace portion from cross sectional areas, either by cutting the bones or X rays CT scanning them or looking at natural breaks.
John Fronimos: We can do this in two dimensions, using the Cross sectional area of airspace relative to the total cross sectional area of the bone.
John Fronimos: Previous studies have have looked at this across a range of sauropod taxa including.
John Fronimos: bazell titanosaur forums and titanosaur.
John Fronimos: And this is shown a range of values, but we see the greatest range of values within individual body regions and usually within a single bone from one part of the bone to another that we have sections.
John Fronimos: So you can see, particularly large ranges in the cervical region, the neck a more limited ranges in the DORSAL region or the torso between shoulders and hips.
John Fronimos: And then we have limited data for the tail the lamb and the ribs but that's in part because those are regions that are not new monetized and all groups.
John Fronimos: For the DORSAL vertebrae we do have some data deficiencies there we don't have as many samples.
John Fronimos: I can say across the board, the number of individual skeletons that have been analyzed in this way is limited so we're dealing with smaller sample sizes, then we'd really like and that limits, some of the questions we can currently answer.
John Fronimos: One of the questions that interests me the most is the evolution of airspace proportion.
John Fronimos: So the taxi you see marked in red and marked with be at the bottom have these airspaces that consists of a small number of large Chamber is called gamma Ray as in camera source.
John Fronimos: While those marked in blue the titanosaur of forms, including titanosaur is have a large number of individually small chambers called MLA.
John Fronimos: And so there seems to be a transition from camera to compel a new material it with the rise of the titanosaur forums that become dominant.
John Fronimos: Towards the end of the cretaceous period, and so I would love to know what the functional implications of that are.
John Fronimos: um but unfortunately we don't currently have enough data to say if there's a significant difference in the aerospace proportion between Cameron and calculate bones, we might predict, for example, MLA might have more.
John Fronimos: bony structure tribeca around them that decrease the airspace proportion in exchange for some other benefit, but we can't currently say that, based on previously published data.
John Fronimos: So the objective of this study is really to expand upon our overall sampling.
John Fronimos: With a focus in this case on the Titanic souls trying to add to the single measurement we have of titanosaur aerospace proportion in the DORSAL region.
John Fronimos: As well as to expand to include the alien which has not been sampled before and the ribs which have not been sampled before.
John Fronimos: Although I won't be presenting any rib results today, those are still pending, but will have results for DORSAL vertebrae and for the helium.
John Fronimos: So hopefully this will enable us to make better comparisons and get a better understanding of how airspace proportion varies between taxa and why that might be.
John Fronimos: So the study of the specimen i'm going to describe today is one that Tom Lehman and myself, published on in 2014.
John Fronimos: it's looks like it could be allosaurus San Juan, and says, but it's not quite it doesn't quite have enough diagnostic features, to be sure.
John Fronimos: That the bones marked in blue represents one semblance that we're confident is a single individual we have comparable size elements we have paired left and right elements and nothing redundant.
John Fronimos: So for the blue material i'm confident and treating it as one individual and we have DORSAL vertebrae we have the alien and the ribs which aren't marked in here, so we can expand our sampling for those critical areas.
John Fronimos: The methods we've used here.
John Fronimos: require us to work with cross sectional areas.
John Fronimos: And in this case we've sampled the material using natural breaks so while preparing the specimen we saw that many of these natural brakes were relatively clean and enabled us to look closely and identify the bone in the aerospace proportion.
John Fronimos: So this is a cheap and efficient method, but it does have some drawbacks compared to either cutting the bones or using X rays CT scanning.
John Fronimos: Particularly being that we cannot control the location of the brakes, although we can be choosy among the brakes that we have.
John Fronimos: And also, we can't control to make sure that all the brakes are a flat plane, so we have a risk if we're not careful, of picking some breaks that might curve into a third dimension and create some perspective distortion.
John Fronimos: So we have to be picky to exclude parts of the breaks that are sticking into a third dimension, so it does limit some of the sampling we do, but we still have a lot of good breaks, we can look at.
John Fronimos: And finally there's also an issue that occurs, regardless of your method of getting the Cross sectional area, which is that sometimes the outer layer of bones falls away and that can lead to a.
John Fronimos: artificially inflated airspace proportion and i'll try to address that when it when it appears i'll try to mention that that might be an issue.
John Fronimos: So our methods were to take photographs of these natural breaks and then digitize them color coding bone in one color and aerospace in another, as you can see here in this neural spine.
John Fronimos: And so, in a perfect world we'd be able to automate this and we would have clear differences in the color of the bone versus the matrix that's filled them in.
John Fronimos: This is not a perfect world, and so you can see all sorts of color data here, and so we had to manually digitize these differences, fortunately, you can tell the difference quite clearly when you're up close with that, based on texture.
John Fronimos: But this required us to take the photographs and then digitize them while looking at the actual bone in front of us to make sure we didn't mistakenly mislabeled anything.
John Fronimos: But with that we were able to digitize bone and aerospace put them into these two tone images and then take them into image editing software to calculate the percentage of airspace.
John Fronimos: And a lot of people use image J for this, but we used our GIs because, being a geo science department, we have a lot of.
John Fronimos: Students and faculty here are very well versed in our GIs and so it's good at these um classification issues to turn these two color coded and basically pixel accounts into an aerospace proportion.
John Fronimos: And so i'm going to show you some of the results for a few major body regions and then we'll discuss what they might mean.
John Fronimos: So here, you can see an anterior DORSAL vertebra This is one from close to the shoulders, where we have three sections Nero spine transverse process and the posterior rim of the centrum we have a lengthwise.
John Fronimos: section in the works as well, and so you can see, the highest value here is point seven seven that's 77% air and just 23% bone which is considerable it's not record setting but it's fairly high.
John Fronimos: The other values are lower closer 2.6 you can see the rim of the centering here with some of these closely spaced chambers.
John Fronimos: Now let's compare that as we move backward through the vertebral column towards the hips.
John Fronimos: here's a similar vertebra from close to the hips we see the neural spine pictured it right has a airspace proportion of point seven which is equal to 70% air.
John Fronimos: But values are as low as almost 50% in the the rim of the post area margin of the central me here.
John Fronimos: So there's similar values, but we do see somewhat higher values in the anterior DORSAL vertebra currently we don't have enough systematic data across tax to see if that's a common pattern, or if that's.
John Fronimos: You know within normal variation whether that means something functionally significant about the two regions, we can get a feel for the range of values, we see in different parts of the DORSAL vertebra.
John Fronimos: The results i'm most excited about our from the alien because no one has to the best of my knowledge, published airspace proportion values for a sauropod alien before, this is the upper most hit bone.
John Fronimos: And so let's take this section here through the base of the illiac blade that gives us a pretty high aerospace proportion of point seven six.
John Fronimos: here's what that looks like there is some potential for this being enhanced by some of the loss of cortical bone so it could be a little bit lower than that.
John Fronimos: We also look looked at a mark part of the medial surface that you can't see here and got a value of point seven four and we have some others in the works through the rest of the blade so we seem to be getting values initially over Point seven.
John Fronimos: But now let's take a look closer to the asset tabular surface of the base here, which is the the joint surface for the hip socket.
John Fronimos: me see through the issue pinnacle a value of just point four two and through the pubic key dunkle a value of absolutely zero there are no air chambers there it's fully a pneumatic.
John Fronimos: And so, this shows us that when we start to sample across the whole element, and we are attentive to that we can see variation from very high to very low values.
John Fronimos: We can even map out the extent of new materiality within the bone showing a couple of major regions around the joint surface and the.
John Fronimos: Pre assa tabular process, which is a major muscle insertion area that do not seem to be new metal is this may be, for reasons of strength, where there are much greater stresses being applied.
John Fronimos: And so the big lesson for me here is that there's a region in this phone that is new monetized with seemingly comparable amounts of airspace to what we see in the vertebral column, but there are also these regions that are not new monetized.
John Fronimos: So let's take those results and feed them back into what we've seen from previous studies.
John Fronimos: So we've expanded our sampling of titanosaur DORSAL vertebrae where previously, we had one measurement of just point five, five now we've seen a greater range so that was not entirely representative, and now it seems to overlap pretty well with what we previously seen with camera source.
John Fronimos: we've also added the data for the helium which includes comparable values to the vertebrae but also some a pneumatic regions and then, as I said, the written values are pending.
John Fronimos: So we're still adding to what I hope will someday be a very large data set to give more statistically significant conclusions, but right now, what I can say for the DORSAL vertebrae is they don't appear to be dramatically different from what we see in.
John Fronimos: Despite the fact that those tax I have these.
John Fronimos: Fewer but larger chambers, the camera and the titanosaur is have a larger number of small chambers, the MLA.
John Fronimos: If there's a significant difference between them and airspace proportion, we might think that that was somehow an evolutionary driver to either increase the airspace proportion or get some other functional benefit that would come.
John Fronimos: That would.
John Fronimos: be worth more to the organism, then the weight reduction from the aerospace but we don't see any systematic pattern here, and this is something that matt well previously proposed.
John Fronimos: Was that Cameron and Camilla new Mississippi despite their obvious differences might be seeming to work out to similar airspace proportions in the living animal, at least in a given region of the body.
John Fronimos: I definitely think we need a larger sample size to establish that clearly, but what we see so far, you know I might have hoped to go into this and see some some great differentiation of the two that would make it obvious there was some functional difference and we don't really see that.
John Fronimos: So to summarize what we've taken away so far we've expanded our sampling of measured airspace proportions in titanosaur is to include more DORSAL vertebrae and the first results for the helium with ribs pending.
John Fronimos: To give us a better sense for weight reduction and the function of this pneumatic chambers in these animals.
John Fronimos: The results are at least, broadly speaking, comparable across sauropod plaids despite variations from La to camera internal structures.
John Fronimos: there's not enough data here to be statistically confident in that, but within the spread of data so far there's substantial overlap to where we can't you know start to say that there's an obvious difference.
John Fronimos: And if it turns out to be true that calculate and Cameron new materiality provide similar aerospace proportions.
John Fronimos: than the evolution from one to the other would seem to be neutral with respect to aerospace proportion and body mass and we would have to look for some other functional explanation for what drove that change.
John Fronimos: So those are the big takeaways that I see here and in the future we really look forward to expanding to bigger and bigger sample sizes, especially for things like the alien where this is the first of its kind, and I look forward to seeing the patterns that emerged from that.
John Fronimos: So i'd like to thank you all for your time and attention and i'm happy to take any questions, it looks like there's about three to four minutes remaining where I can take those questions.
Tom Tobin: There is a question in chat john.
Tom Tobin: When Lou says good talk, did you see any patterns of the new mentality morphology and body size.
John Fronimos: that's an excellent question is one of the biggest things, we might ask is, do we see a greater aerospace proportion in larger bodied animals as as sort of something compensatory for.
John Fronimos: compensating for that body mass and currently unfortunately we don't have a large enough sample size to plot this against body mass.
John Fronimos: But that's something that I definitely want to reach a point of doing long term is to sample enough if we see a clear trend that you know, the largest.
John Fronimos: bodied sauropods have a very high aerospace proportion that would lend some support to you know body mass as a driver of these these counter balancing features so that's a long term goal, but not something that we have data on yet.
Rindsberg, Andrew: i'm forgive me if I miss something obvious like I came back a couple of minutes late from the break how far back does new materiality extend in the fossil record.
John Fronimos: that's an excellent question, so I didn't talk about the evolution of it before outside of sauropods but we see new entity evolve several times among archosaurs and i'm talking purely about post cranium limited city, because many other organisms have sinuses and things like that stone.
John Fronimos: But post colonial new entity in archosaurs independently seems to evolve in pterosaurs in theropods where it's shared by birds today and in sauropods so.
John Fronimos: It seems to be to the best of my knowledge, I don't have a pre triassic example of post cranium limited city, although if someone's aware of one i'd be very happy to know about it.
Rindsberg, Andrew: But not in any of the pre mammal or pre mammal lineages.
John Fronimos: So we don't see any post cranium luminosity in mammals outside of some married maybe very hard cases like perhaps some.
John Fronimos: You know, some throat chambers and certain primates or something like that, but.
John Fronimos: It seems to be something that coincides and archosaurs with a very complex long morphology with a they basically have lungs that have these additional air chambers that come off that vent.
John Fronimos: that's what i'm looking for ventilate the lungs and they seem to expand and other regions of the body and nothing like that is known in mammals, so there is some possibility that.
John Fronimos: Body size limitations in mammals compared to sauropods might be in part due to differences in the respiratory system.
Rindsberg, Andrew: Well, thank you.
John Fronimos: Thank you.
John Fronimos: I have, if I have time, I have one more question in the chat from rowan lockwood about other possible functions for new entity, please cut me off if I if I am go long on that, but.
John Fronimos: Other possible functions for new entity that's an interesting question when i've thought about and I haven't come up with something other than specifically weight reduction.
John Fronimos: I don't expect that those extensions of the lung tissue into the the post cranial skeleton are actually involved in gas exchange that's only an intuition I haven't actually seen testing of that.
John Fronimos: that's just based on the unlikelihood of being able to force air through all of these um these small passages, and the fact that I don't think the air sacs beyond the lungs themselves and birds or respiratory are involved in gas exchange.
Tom Tobin: Think we're basically out of time, so if you could you could switch over to.
Tom Tobin: That David tremors up next if you're ready to share your screen.
Thank you all for your presence.
David Schwimmer: me get to the.
David Schwimmer: The work.
David Schwimmer: So, assuming everything works i'm going to talk about some current updates on the dinosaur record in the southeast and start with, let me define the term.
David Schwimmer: southeast province in this concept for the lake cretaceous includes everything from Missouri up through North Carolina.
David Schwimmer: There is a distinct northeastern province that's been pretty much centralized in Delaware New Jersey and Maryland but nothing really much in the lake cretaceous in Virginia, so we have a natural boundary there.
David Schwimmer: what's really interesting is that we've vastly increased our knowledge of dinosaurs in the southeast and the past 30 years.
David Schwimmer: I pick 30 years because essentially there's about three decades of new material to report prior to 1990 this was the published systematic dinosaur record.
David Schwimmer: And i'm only discussing formal systematics here not just anecdotal reports.
David Schwimmer: And pretty much you'll see that, to my knowledge, everything before 1990 was essentially from Western Alabama and the so called Selma jock a single hadrosaur road hadrosaur more of lower limb from Mississippi in the San Antonio and actually information and.
David Schwimmer: material from North Carolina entirely from previous landing reported by halsey Miller and then updated by Baird and horner and 79, this is the, to my knowledge, when I arrived in the south, the pre 1990 data.
David Schwimmer: The only skull we had of any kind, any cranium material was the type of the fourth one which is not in great shape, but it was a definite hadrosaur morph.
David Schwimmer: At the time, referred to as a header sorted by one langston and, by the way, there is currently an updated.
David Schwimmer: Publication by Terry gates and James lamb on another specimen and look for a thon I.
David Schwimmer: I just asked Terry about this yesterday it hasn't yet been impressed but there's going to be a revision of a fourth on also making an older than the original publication date it's apparently the type is actually San Antonio not campaign.
David Schwimmer: This is the current status of our dinosaur knowledge in the southeast and, in addition to a number of tax or which i'm going to go through the also increase the range.
David Schwimmer: The geographic range, as well as the our knowledge will get to the specifics i'm going to go through each of these very quickly, of the updated publications.
David Schwimmer: And another way of looking at this, we also now have fossils from Georgia dinosaurs from Georgia Tennessee.
David Schwimmer: up a phone from South Carolina which i'll be talking about and we've also probably most interesting these exes are Mr mission dinosaurs, which had not been reported until fairly recently.
David Schwimmer: Actually i'll be honest, one of them isn't reported, because one of my specimens but it hasn't been published, yet so i'm i'm fudging a little bit.
David Schwimmer: But we also have new San Antonio material and a fair amount of new campaigning material so basically we have dinosaur foreigners in southeast all the way from the San Antonio through the very end of the discussion.
David Schwimmer: So chronologically here's some of the new updates and if you even need specific publications, I can provide data or.
David Schwimmer: pdfs if anyone's interested.
David Schwimmer: First reports of dinosaurs from Tennessee was publication by john Ryan at all in 1991 and it's basically pretty worn parts of a large hadrosaur more.
David Schwimmer: From the coon creek formation, which would be at the time, probably campaign Ian, although the dealings little rough.
David Schwimmer: In 93 I and others published the first phone from Georgia and East Alabama with both tyrannosaur road and hadrosaur material.
David Schwimmer: At the time I tend to be for this to the fourth on the Alabama mature specimen and I tentatively referred this to Alberta source.
David Schwimmer: This subsequently i'm pretty sure is actually appalachia source which we'll get to in a moment, interesting bone, by the way, this is the fourth metatarsal of this hadrosaur these bones, are all in association, the fourth metatarsal is a little tiny splint leftover bone.
David Schwimmer: Basically vestigial bone is very rarely seen.
David Schwimmer: In.
David Schwimmer: K Karen and I described the first dromey a sore, which is a tiny little tooth know the size of this thing it's about four millimeters long.
David Schwimmer: it's a very small jamia sore but it the teeth are identical to the teeth of this guy from the learn mode side of the continent, which is sort of less these lengths tonight.
David Schwimmer: This comes from the mortal formation and it's probably early campaigning little hard to date this tooth it was it was basically in float.
David Schwimmer: Probably the most notable dinosaur we've have in the southeast now was the 2005 description of appalachia source by Tom Williamson Tom car myself and the white portion of this is the actual bones that had been found.
David Schwimmer: At that in the in the type specimen we have additional referred specimens, including from Western Georgia.
David Schwimmer: But this was the first theropod with a skull that's been known from the southeast not complete, but good enough to recognize it as being a basal tyrannosaur ride it's got some ornamentation on the measles, and a few other details which suggests fairly basal in the Toronto sort of clade.
David Schwimmer: There is a minor controversy about the forearms I have to say a little bit Florida when I saw the reconstruction with the gigantic forearms and three fingers, because this would be the more plausible.
David Schwimmer: Reconstruction, given that we had actually know for limb material in the type specimen but apparently was based on this specimen which was assumed to be the humorous, but I think I can argue that that's not really a humorous failsafe just very briefly, partly because this.
David Schwimmer: This flange was supposed to be the death delta pectoral CREST.
David Schwimmer: And if you took this reconstruction with the delta pectoral CREST in that position that would pull the arm straight into the shoulder from outside the body cavity which is not very plausible.
David Schwimmer: Rather than being being a lateral excursion, which is the normal way the delta pectoral CREST works, if you look at every of theropod.
David Schwimmer: The delta pectoral CREST and the month breaky Alice with will the the femoral COR COR COR COR Rico ideas basically pulls it into a rotation, not a lateral excursion.
David Schwimmer: If you look at the reconstruction with the short arms that makes a whole lot more sense.
David Schwimmer: And if you look at this bone and you look at this bone you'll notice they're almost a perfect mirror image.
David Schwimmer: And that bone happens to be a pubic bone from source as as a model so i'm.
David Schwimmer: pretty sure that's a pubis however it may not be from the same individual that's another interesting story, because it is larger than the other pubic bone in the reconstruction, so there is still a little bit of a mystery here.
David Schwimmer: Moving on, in time, because time is limited.
David Schwimmer: In.
David Schwimmer: l Sanders and I and number of people published a monograph in the American philosophical society transaction on cretaceous reptiles and vertebrates from South Carolina and including.
David Schwimmer: Some good ortho items for material a femur and bunch of uncles and a few vertebrae and a bunch of small theropod teeth.
David Schwimmer: And that particular set of teeth looks very much like the sauna felicities from the from Western Alabama and i'm pretty sure we're looking at a population of little bitty dromey sores in the southeast that are finally getting recognized.
David Schwimmer: In 2016 page markets that all ever erickson and ebersole reported a very nice skull of a basal hadrosaur more if they refer to it as to track done Orientalist they it's from the mortal.
David Schwimmer: it's from the San Antonio and portion of the mortgage information, and when I first thought I thought wow that's a wonderful specimen i'm just showing the skull is lots of good post cranium is do.
David Schwimmer: I was a little curious about the relationship between Eo track it on and the fourth on looking at the skulls simply because.
David Schwimmer: Part of the diagnosis is the nasal CREST and I noticed that the nasal CREST on their type specimen is a bladed right there.
David Schwimmer: So I am a little curious about just what it would look like compared to that, but i've been assured.
David Schwimmer: by several people who are more knowledgeable of hadrosaurs than me that they really are different, so will you know will assume there are two basal hadrosaurs.
David Schwimmer: In the southeast One of the interesting questions is going to be, why are all these basal dinosaurs in the southeast are they a relative.
David Schwimmer: or a pioneering fauna, and that is an interesting question we're going to resolve in the future that still is not resolved.
David Schwimmer: or basically and i'll get to this later just how did the dinosaurs get here, did they reject some of these originate here or did they migrate from Asia before the interior see opened.
David Schwimmer: By the way, here's a mandible from Tennessee that's not been published from that.
David Schwimmer: john Brian shared with me now sorry my bad.
David Schwimmer: That it wasn't john's it was Tom give him my gibson's specimen and it's from the concrete formation he's believed working on this, it looks very much.
David Schwimmer: Like the mandible and to track down specimen so we may have a wider distribution of your track done up into the concrete Tennessee.
David Schwimmer: Finally, the last interesting update refers to Sarah tops ian's the presence or absence of Sarah thompson's.
David Schwimmer: In the southeast is a really interesting question because Sarah thompson's generically a lot directly as a large clade appear in the lake cretaceous around the campaign in.
David Schwimmer: In the Western side, North America and during that time we were cut off from learn mode side of the continent by the interior seat.
David Schwimmer: So we would not expect sort of topsy ins to be in the eastern southeastern United States unless they either came in from Europe or originated in the southeast and yet.
David Schwimmer: Nick long rich reported a leptospirosis topsy and Joe fragment of Max Larry fragment which he found in the LP buddy collection he and I exchanged him data about this before he published it.
David Schwimmer: He is he claims that it's a Sarah topsy and fragment because there is this interesting angle in this doll fragment which corresponds to the same angle in the MAC silla of leftists are tops i'm.
David Schwimmer: i'm pretty skeptical, to be perfectly honest, on that because two reasons, one is here's a crocodilians jaw fragment in my collections from Dinesh Lucas.
David Schwimmer: Where it's been twisted literally at right angles in tough tough economic Lee and i'm pretty aware that croc jaws especially are subject to fletcher during preserved preservation because they're just basically long and thin.
David Schwimmer: So when you break off the link leave the wall of a crocodilians joy you're going to probably bend it somehow Secondly, I noticed if I look at the alveoli on the Sarah Thompson specimen or long riches legend so topsy and it doesn't look like the.
David Schwimmer: alveoli you typically find in order efficient material, this is a address or Max Larry fragment but they the tooth sockets tend to be long ridges and rather vertical as opposed to crocodilians alveoli so bottom line is i'm not really sure that's not a crocodilians fragment.
David Schwimmer: So i'm not convinced that we have evidence of certain options based on this, however.
David Schwimmer: In 2017.
David Schwimmer: We have the population of this specimen from the owl creek formation, which is latest administration, and this is definitely a neo Sarah topsy in truth that's it's unmistakable the the fourth group and the ground structure is on the stable and.
David Schwimmer: George Phillips was nice enough to share this with me.
David Schwimmer: This chart from their their publication, which shows very plausibly that by the end of the menstruation we actually did have a land bridge between laryngitis and appalachia so invasion of Sir topsy ins is much more plausible at the very end.
David Schwimmer: Of the cretaceous than earlier in the period and since we can run out of time quickly, let me just summarize.
David Schwimmer: We have a lot of fossils that have not been published here's a large beetle failings from San Antonio and Mississippi.
David Schwimmer: A whole raft of theropod teeth and amateur collections from North Carolina.
David Schwimmer: This is a hadrosaur tibia that i've worked on for a while, from the ripley formation in Georgia, which unfortunately is now back in a private collection, because the.
David Schwimmer: person who found it wants it back and sadly it's going to be lost a science from Fred but some mistakenly a small hadrosaur and weapon or tibia and it's from the latest it's on the description in Georgia.
David Schwimmer: And so, let me conclude we've gotten a great number of new publications about dinosaurs in the southeast we've extended the range to six states from three.
David Schwimmer: We now have some skeleton from skulls usually in marine deposits and there's a huge amount of unpublished material, which means we're going to have many more dinosaur discoveries in the in the future.
David Schwimmer: And with that I think people who contributed to my work over the years and hopefully have a minute or so left a question, so I picked up so much time.
John Fronimos: Actually, you should have several minutes for questions.
David Schwimmer: i'll be glad.
John Fronimos: That four to five, and I see one coming in from man Lou in the chat.
David Schwimmer: Okay, great.
John Fronimos: So the question is, I guess, from Ek, why is Sarah tops and materials so rare in the southeast.
David Schwimmer: it's never been found before, in my opinion before the discovery in the latest version because Sir tops ian's appeared late in dinosaur history.
David Schwimmer: And at that time the interior see blocked migration from the Western side of the continent to the east and we're pretty sure the Sarah tops ian's appear in Asia first.
David Schwimmer: Therefore they had no way to they could migrate from Asia to learn micah during the cretaceous but they could migrate across from Jeremiah across to appalachia.
David Schwimmer: It was that interior see blockage and in all the years of looking for dinosaurs in the entire eastern continent, no one had previously found legitimate certain obscene material.
David Schwimmer: it's one of the that so that pretty much evidence that we were blocked from the West, most of the time during the late cretaceous.
John Fronimos: so that he can also asked, besides the Mississippi specimen do you know of any others.
David Schwimmer: No none whatsoever well again Nick long rich published the paper on that specimen from North Carolina.
David Schwimmer: that's my opinion, this is not a certain topsy in but it isn't press right now so professionally it still exists as a report i'm just will skeptical of it, because to me that looks at my first guess would be that was a crocodilians pregnant.
John Fronimos: And we have a question from Lewis sacco's asking that are most of the SE dinosaurs founded in marine deposits.
David Schwimmer: entirely period, however doesn't mean they were living in the ocean, of course, but they're all basically floating or shore living.
David Schwimmer: specimens that we're watching to see, I have a paper and in 1997 about the telephone interview teflon to me of marine dinosaurs in the East if anyone's interested i'll be glad to send a PDF.
John Fronimos: And I have question in my own, I was wondering I don't know how far back the record goes, I know you mentioned, they are mostly.
John Fronimos: I forget the earliest stage that you said, but is there any evidence of.
John Fronimos: vicarious events associated with the opening of the formation of the western interior seaway or does the record in the East, not go back far enough to detect that.
David Schwimmer: Well, we have a big break between the early cretaceous and the San Antonio we have early cretaceous dinosaurs in Virginia and Maryland in the Iran deal formation, then, is a fairly long temporal break and then we get the late cretaceous record.
David Schwimmer: So we're not quite sure exactly how things got here, in addition to dinosaurs, we have freshwater fish that somehow are found in both sides of the continents.
David Schwimmer: We have crocodilians I, we will pterosaurs easily could fly we have we have some east, west relations in amongst a foreigner but.
David Schwimmer: Clearly dinosaurs worn swimming across the ocean, so it is most probable we cannot prove it, yet that they arrive before these interior see way made a complete block during the San Antonio that's our best or most plausible explanation.
David Schwimmer: And it's but i'm still studying that i'm very much interested in the question that by carrie and sort of how how dinosaurs and other phone got across the interior see way it's one of those things i'd like to focus on for a while.
David Schwimmer: There may have been some islands in between that's one hypothesis, we do have some evidence of volcanic islands in Oklahoma and Arkansas at the time.
David Schwimmer: So there could have been a bit of island hopping but unlike modern mammals, we don't expect them floating across on mangrove rafts during the late cretaceous they're just too big and I don't think mangroves were thing then anyway.
David Schwimmer: So you know.
David Schwimmer: not sure true but, but yet.
John Fronimos: Right Thank you that's a really interesting talk for.
John Fronimos: Those of us here in the southeast and this brings us up now two.
John Fronimos: To 340, which is our break time, so we have a 15 minute break resuming with talks at 355 also drop that into the chat so you have that as a.
John Fronimos: As a reminder, if any of our remaining presenters have any questions or want to try anything out with the The co chairs, please let us know, otherwise we will resume here at 355.
RISE Rowan Lockwood (she/her): hey john.
RISE Rowan Lockwood (she/her): Yes, so I was wondering john and Tom weather and folks that have been sort of back behind the scenes.
RISE Rowan Lockwood (she/her): Whether there's any interest in people getting together and saying hello to each other, we see each other every year at southeast GSA and.
RISE Rowan Lockwood (she/her): You know this year is a little different and I, you know I don't know whether there's interest in doing that, but I wondered if it was okay for folks to say hi to each other, during this break.
John Fronimos: Oh absolutely I think we can leave both available, and you know people can turn their microphones on I think you have the control to do that, so the chance to check in absolutely I think that would be great great.
Tom Tobin: Thanks john Rowe and that would have been kind of my as PS person that I thought about it and, to be honest i'm undergoing a bit of pandemic fatigue with zoom meeting.
RISE Rowan Lockwood (she/her): Oh, my God no anytime anytime I have the opportunity to do.
RISE Rowan Lockwood (she/her): phone these days I do phone, but I gotta say it is really nice to see all of you folks I think I see David Campbell and of course we just saw David schwimmer I think I see tricia and Diana it's really lovely to see folks and Tom I feel like I recognize is that your office.
Tom Tobin: Is yeah.
RISE Rowan Lockwood (she/her): yeah.
RISE Rowan Lockwood (she/her): i've been there, so.
Patricia Kelley: When Carl sold office.
Tom Tobin: I am in carl's old office actually yes yeah.
Patricia Kelley: i've been there too.
Tom Tobin: If i've told us one foot larger than the other offices in the hallway for reasons I don't fully understand.
RISE Rowan Lockwood (she/her): Oh, my God you lucked out look at.
Patricia Kelley: That.
Patricia Kelley: i'm saying that.
Tom Tobin: I would trade that for a window to the.
Tom Tobin: outside any day but.
RISE Rowan Lockwood (she/her): I see Andy.
RISE Rowan Lockwood (she/her): i'm really missing missing myself these GSA buddies i'm missing our like our usual lunchtime out or you know get together.
Patricia Kelley: For now.
So.
David Schwimmer: The next fall's SVP online again.
RISE Rowan Lockwood (she/her): Oh, did they decide.
Patricia Kelley: Oh yeah just shared that is that in September.
David Schwimmer: Usually, but they I think they were just anticipating too much trouble you know shutting it down if necessary.
David Schwimmer: huh yeah it's too bad I was kind of hoping to go up there.
Patricia Kelley: i'm still hoping portland's in person hmm.
RISE Rowan Lockwood (she/her): yeah they haven't made a decision on that yet have they.
know.
RISE Rowan Lockwood (she/her): And Diana Where are you located for you based.
Diana Ortega-Ariza: Lawrence Kansas.
RISE Rowan Lockwood (she/her): gotcha okay.
Diana Ortega-Ariza: hey David.
Diana Ortega-Ariza: I was an assistant professor at Columbus State University yeah I was there for three years and happy to see David.
RISE Rowan Lockwood (she/her): Oh Jennifer Nestor you know is saying and the GSA will definitely be in person in portland.
Patricia Kelley: Oh yeah.
RISE Rowan Lockwood (she/her): That is exciting yeah.
Patricia Kelley: Right.
RISE Rowan Lockwood (she/her): And shout out to Jennifer, thank you for holding the career events and things for students at this meeting really appreciate it.
David Schwimmer: yeah no you in clink we're gonna have a field trip on this meeting do that.
Diana Ortega-Ariza: What happened, yes, actually we we let a virtual field trip yesterday.
David Schwimmer: Okay virtual field.
Diana Ortega-Ariza: Well, good attendance.
David Schwimmer: You were lucky because we had incredible range stroke lesson.
Diana Ortega-Ariza: Where people.
Tom Tobin: chuck want to do the Bosco landing trip they like yeah if it had been in person that places complete, like all of our rivers are almost being fully now.
RISE Rowan Lockwood (she/her): That tell me that time i'm supposed to do field work, I think, in May.
RISE Rowan Lockwood (she/her): yeah down in Alabama so.
It might.
Diana Ortega-Ariza: Over filter it, you know getting wet and talking and doing that thrives on.
Diana Ortega-Ariza: As part of the.
adventure.
David Schwimmer: Also really heavy rain does a great job of scaring the outcrop remember when you create.
David Schwimmer: The bones pop out.
David Schwimmer: You need.
Rindsberg, Andrew: I need to know I enjoyed your field trip and one of the things I enjoyed was being able to see the strat sections, without being in the front row.
Diana Ortega-Ariza: Back yeah.
Rindsberg, Andrew: and your photo micro graphs and the other.
Rindsberg, Andrew: and using Google Street View That was something i've never seen.
Rindsberg, Andrew: So you were quite inventive, I really appreciate it.
Diana Ortega-Ariza: You know you have to be so creative when this like instead of going to the field and hearing the rocks and creating a filter and trying to make it as engaging as if you were looking at the rocks that's challenging.
Diana Ortega-Ariza: So so yeah we were.
Diana Ortega-Ariza: Trying to make it.
Diana Ortega-Ariza: Like yeah you're enjoying the rocks as much as.
Diana Ortega-Ariza: You go in the virtual world.
Rindsberg, Andrew: Well, we didn't have the chatter in the bus, but on the other hand, we didn't have to smell 40 but geologists.
either.
RISE Rowan Lockwood (she/her): Thank you for that and.
Rindsberg, Andrew: And I must say if i'm sitting here in my own home the bathrooms are better.
RISE Rowan Lockwood (she/her): how's everybody doing I know it's been just such an incredibly difficult year.
RISE Rowan Lockwood (she/her): Everybody hanging in there, I know tricia you're out in the Pacific Northwest right.
Patricia Kelley: yeah I haven't been home since February of last year, but my husband came out or we could go, and so I have seen it, I went for a whole year and 10 days without seeing my husband.
Patricia Kelley: But on the other hand, i've had lots of time with the grandsons no no time to see my granddaughter in Virginia, but yeah i'm primary child care for my grandson's.
There you go.
RISE Rowan Lockwood (she/her): How about everybody else has everybody has to.
David Schwimmer: learn how to do online courses.
RISE Rowan Lockwood (she/her): So one of my students rosemary's here and.
RISE Rowan Lockwood (she/her): Rosemary guardado.
RISE Rowan Lockwood (she/her): And she can tell you I think in in William and Mary we have all in theory we've learned how to do online courses, but i'm not really sure in practice we've learned how to do it we're trying that we definitely haven't easy as i'm in the geology department which we're trying or.
Tom Tobin: i'm feeling right now it's like.
Tom Tobin: We did we canceled our spring break and so like right now is when i'm normally like refreshed and ready to go and now it's like oh my God so kind of the month.
RISE Rowan Lockwood (she/her): yeah we have spring break dates.
RISE Rowan Lockwood (she/her): That are distributed they're supposed to be distributed out but um I don't know how Rosemary feels, but I feel like I Those are my days to catch up on all the work I didn't manage to get done on the other days.
Rosemary Guardado (she/her): I haven't been able to fully take a.
Rosemary Guardado (she/her): break off on on any of my screen right days so far, because, like rowan said.
Rosemary Guardado (she/her): I either I I knew this is going to happen, the met in the moment they mentioned that we had spring break days I was like okay well, will you marry students are going to use those days of catch up on work that they fell behind on so.
Rosemary Guardado (she/her): fortunate but.
David Schwimmer: On the other hand, will be so nice to get back to the office and classes next fall, which I assume we're going to do.
David Schwimmer: i've scheduled online courses for the summer, but i'm going to definitely have fall in love in person courses in the fall.
David Schwimmer: i'm sure it'll really feel refresh just getting back in you know actually seeing a student or two.
Rindsberg, Andrew: yeah.
Rindsberg, Andrew: Sure sure yeah you're in your recently retired, how do you feel.
Patricia Kelley: me.
Rindsberg, Andrew: that's has covered made much difference in your lifestyle.
uh.
Patricia Kelley: Well, I haven't been in a store since February, a year ago I spent all my time taking care of grandchildren and you know time I squeeze in my failure society and awt responsibilities when I can but yeah i'm so glad i'm retired and I didn't have to pivot into online teaching yeah yeah.
Patricia Kelley: i'm going to pop out and go here Tony Martin give this talk I think he's up now so i'm so glad.
Rindsberg, Andrew: He was in this session.
Patricia Kelley: I think he's in a different room.
Rindsberg, Andrew: What Oh well, I better.
Patricia Kelley: Thanks for suggesting this round so glad to see.
You.
RISE Rowan Lockwood (she/her): hey Kate welcome.
RISE Rowan Lockwood (she/her): Mary student who's uh who's joining us so David I was trying to figure, are you still Where are you these days.
David Schwimmer: Still Columbus Georgia I updated my Facebook page and somehow it seemed to think Mike when my Grad schools where i'm teaching.
David Schwimmer: Nice bonus.
David Schwimmer: up here in Georgia, I probably stay here till they carry me away and put me in the fossil collection.
RISE Rowan Lockwood (she/her): As about to say, does that mean you go straight to the fossil record are.
David Schwimmer: pretty much I mean i'm the longest serving faculty in my university.
RISE Rowan Lockwood (she/her): Are you really.
David Schwimmer: 43 years this wow yeah good thing about it, you know you can keep on doing the same old same old at you, they don't kill you or something.
David Schwimmer: And the students are pretty pretty good about it so far yeah I have new Grad student, by the way, is a dinosaur who's a dinosaur fan.
David Schwimmer: Is.
RISE Rowan Lockwood (she/her): going to work on.
David Schwimmer: So he's well he's in generally interested in eastern dinosaurs so i'm going to get them up to speed and have them carry on, and I think i'm gonna have them address that by karen's question is a big topic.
David Schwimmer: Because I wondered, I was gonna ask you if you're going to follow up on that that's.
David Schwimmer: Great that's like that's the major question I think it's just harder or dinosaurs get her or did or these ancestral populations that actually spread so where else okay it's it's been hypothesize both ways.
RISE Rowan Lockwood (she/her): I have to admit I spend so much time thinking about moleskine populations on the coastal plain and you know what's happening in terms of moleskine biogeography until your talk, I really hadn't thought about dinosaur biogeography on the coastal plain so i'm i'm clearly missing out here.
David Schwimmer: A little spawn quite the same way.
RISE Rowan Lockwood (she/her): to broadcast funding and dinosaurs what that's not a thing.
David Schwimmer: That you know little project, the exit well.
RISE Rowan Lockwood (she/her): I see David Campbell is smiling at the thought of it.
Rosemary Guardado (she/her): I have a question real quick so who will be presenting on like Rachel moore's after the break and everything on to the back to like the last session and everything who's going to be doing the zoom chair.
Tom Tobin: i'm going to be doing the posters and things like.
RISE Rowan Lockwood (she/her): Okay, this is Rosemary Rosemary this is.
Tom.
Rosemary Guardado (she/her): hi I just have one request, so I was looking at, like the other previous poster presentations and everything and i'm actually the way that I recorded my presentations that I did slides and everything, and so I think it'd be best if you've maximized the the like screen in the corner.
Tom Tobin: Just let me I can we got four minutes I can do it will tell me what you like and don't like.
Rosemary Guardado (she/her): that's exciting right because, like, I saw that people you because, like.
Rosemary Guardado (she/her): i'm to give you some contacts and everything, while we were while are a little Paleo I was like coffee no se GSA.
Rosemary Guardado (she/her): We are giving suggestions like oh Maybe she shows like you know figures from like here a lot they come get a poster basically.
Rosemary Guardado (she/her): And so that's what like we did, and everything and then like coming here and I realize everyone it's like talking and everything I was like oh my God you can't even see whatever reason for that so yeah So if you look at the little right there, so you know it's really tiny high maximizing.
Tom Tobin: For you on this screen maximize.
Tom Tobin: Yes, yes.
Rosemary Guardado (she/her): yeah.
RISE Rowan Lockwood (she/her): And so, Tom that's going to be to for.
RISE Rowan Lockwood (she/her): rieger darko and for calling Norton Kate do you want to do it for years to.
RISE Rowan Lockwood (she/her): yeah and katie mckinney.
Tom Tobin: Okay, so for all so i've got my schedule here to give you my three posters perfect all right i'll maximize your small screen every each one of those yeah because some people have it where it's like zooming around on the poster and they're talking about it and.
Tom Tobin: yeah that works.
Rosemary Guardado (she/her): Great Thank you.
RISE Rowan Lockwood (she/her): Oh, and I have to give so Rachel I have to give you a shout out, we read yours and tom's geology paper in my paleontology course a couple weeks ago.
So.
Rachel Mohr: Did they like it.
RISE Rowan Lockwood (she/her): They did yeah they liked it a lot so lots of questions about sclerotic chronology lots of questions about you know.
RISE Rowan Lockwood (she/her): You know these these two intervals, and you know the drivers of the KPMG for folks that don't know Rachel had a really great paper in geology basically getting at.
RISE Rowan Lockwood (she/her): Looking at changes in delta see 13 seasonally leading up to and beyond the KPMG and looking at how that corresponds to you know things like the deck and traps versus the the bowl light and backed.
Tom Tobin: Up we're really hoping for temperature, but it just turns out, they don't record temperature.
RISE Rowan Lockwood (she/her): yeah you did a good job of explaining it in the paper, though, so good.
This was a.
Tom Tobin: result, a lot of work to squeeze that into a geology man is.
Tom Tobin: so little space.
RISE Rowan Lockwood (she/her): yeah just not I mean it's great because you're going to get really good coverage and everyone's going to cite it and.
RISE Rowan Lockwood (she/her): And all that, but it there you don't have much space to work with.
So much.
Tom Tobin: Unfortunately, being like cut like the way it was cutting really kind of a little pieces off here and there, you can't really compile them into like a second manuscript because they're, just like the edges, rather than like the meat of another thing but.
yeah.
Tom Tobin: The group Michigan Sierra peterson is doing some work that we can kind of that are so Rachel stuff will contribute to as well.
RISE Rowan Lockwood (she/her): yeah actually um that's the grant that Rosemary and I are on Cory meyers currently peach Sierra peterson one yeah cool.
Tom Tobin: Was that a friends or is that.
Tom Tobin: Is that a French Fries grantor ftp or.
RISE Rowan Lockwood (she/her): SGP yeah yeah.
RISE Rowan Lockwood (she/her): let's see what's press.
Tom Tobin: frontier research and her science it's for like.
Tom Tobin: Jeff Walker the for.
RISE Rowan Lockwood (she/her): yep I got it, but now it was it was classic SGP it was yeah dnn company cool.
Tom Tobin: Alright, we are coming up on our next topic.
Tom Tobin: Rachel that unix yeah.
Tom Tobin: yeah you want to get your screen going.
Rachel Mohr: You see, the phone screens line.
yep.
Tom Tobin: We got one minute, or something.
John Fronimos: While we're waiting, we can mention one more time I guess for anybody who's joining us after the break.
John Fronimos: you're in interactions of environments and life a schedule says during the paleozoic that this is really fan results so.
John Fronimos: expect to the range from mesozoic downward at this point.
Tom Tobin: Do you think got it wrong at one point that we want to correct it and they're like no corrections are allowed or yes we we got stuck with it.
Tom Tobin: we're good to go john you want me to introduce or you want to start it either way is fine.
John Fronimos: I can go ahead and introduce this being the last of them has been split up so welcome back to the break, as I said, our next talk command we have Rachel more and Thomas Tobin i'll go ahead and turn the floor over to you.
Rachel Mohr: Alright today i'm going to tell you a little bit about an ongoing project we have investigating the class and histories genus of ammonites and like cretaceous of Alabama.
Rachel Mohr: The ammonites are super diverse group throughout the cretaceous and because of their unique properties being abundant and widespread and often face she's independent.
Rachel Mohr: they're very useful for bio strategic for us for bias redick donations and correlations, and in particular the Plaza and his service genus of ammonites maybe especially.
Rachel Mohr: useful for bias photography it has that potential in that it's an especially abundant genus of ammonites and it's found worldwide.
Rachel Mohr: In their cretaceous so it could be super useful, except for what else is high at coined the species problem in 1903.
Rachel Mohr: And what the species problem is for this genius is basically that this genius has so many different varieties in form and shape.
Rachel Mohr: That it's hard to draw the lines between species to know exactly where you should group all of the individuals.
Rachel Mohr: So, since this geniuses first studied nearly 200 years ago, this has been identified as a problem there's currently over 130 species name worldwide, but the differences between the species still aren't that clear and it's kind of an ongoing puzzle.
Rachel Mohr: So even higher himself in his 1903 posthumous manuscript he is responsible for naming and describing a vast majority of the important species present in North America.
Rachel Mohr: But he also kind of waffled between the idea that maybe instead of like 32 species, maybe they were all one species and he couldn't make up his mind between these two hypotheses.
Rachel Mohr: And then, in recent years there's been a lot of ongoing work where a lot of authors are reconsidering this genus of class in history is is possibly being over split so.
Rachel Mohr: there's a bunch of species in Texas, and Europe and in South Africa that have been recombined into singular species in those areas and a recent dissertation by Karen wagoner suggested that perhaps there's some file attic gradualism at play in this group as well.
Rachel Mohr: So to just take a little bit of a bite sized chunk out of this genus we're approaching a relatively small geographic area just Alabama and neighboring counties.
Rachel Mohr: And we're also focusing on a limited range of time, the San Antonio through most European time periods of the lake cretaceous.
Rachel Mohr: And within these confines and the published literature and in museum specimens and the labels associated with them there's possibly many.
Rachel Mohr: As many as eight different species of this genus present, but the approach that we're going to take here is to kind of set aside those previous species designations.
Rachel Mohr: and try to approach the population from a more quantitative.
Rachel Mohr: way so we're going to collect more metric measurements of all of the class and histories individuals available and some major collections from this area.
Rachel Mohr: and try to characterize the population quantitatively, to see whether or not there are distinct morphological groupings that are supported by that data.
Rachel Mohr: The specimens that are part of this study are the class and histories individuals available in these three major Alabama fossil collections, including the geological survey of Alabama mcqueen science Center in Birmingham, and the Alabama museum of natural history.
Rachel Mohr: Of.
Rachel Mohr: variables relating to the size of different features on the shelf, such as diameter world height world with venture with.
Rachel Mohr: The width of the umbilical which is kind of the Center part of the world, the distance between septum along the Venter.
Rachel Mohr: And then the positioning and counts of the three main types of tuber goals, which are these little ornamental bumps found on mini plus of history specimens it's all together these direct measurements of shells are considered the raw more for metric data.
Rachel Mohr: We also had some calculated variables to kind of normalize some of these size variables to account for different size specimens so if there's a change in the world shape towards bigger specimens these ratio variables will account for that.
Rachel Mohr: So morph metric measurements were taken in many places on multiple different locations on individual shells, as they were available.
Rachel Mohr: and, overall, there were nearly 210 specimens measured for nearly 2000 individual measurements.
Rachel Mohr: And, since this is a project that involves multivariate statistics before we get into those I want to address some problems that often occur with multivariate statistics and missing values.
Rachel Mohr: Which missing values are nothing new to the paleontological field, just because not all fossils are perfectly preserved so we are going to have missing values in our data, and we do.
Rachel Mohr: Although the multivariate statistical analyses that we would like to run require complete rows of data only so there's three approaches that we can take to get around these missing values, and we will compare all three of these methods.
Rachel Mohr: One the most simple way is to remove enough specimens or variable so that you no longer have any incomplete holes in your matrix.
Rachel Mohr: But that, obviously, is going to reduce the number of assessments and variables that you can investigate so it's not ideal.
Rachel Mohr: The results i'm going to show you today are based off of the second method which is using the Miss mda package and our to use an iterative PCA algorithm to estimate missing values.
Rachel Mohr: And a third way, which is going to be the next step of this project is to do sort of the manual amputation, by taking the known relationships of variables within an individual and extrapolating that to broken or incomplete positions.
Rachel Mohr: So the first.
Rachel Mohr: Analysis i'm going to show you here is the principal components analysis which is kind of the main multivariate statistical methods that we're using.
Rachel Mohr: And this first data set is all of the class and testers shells 202 of them, and all of the raw more for metric measurements like I showed you before.
Rachel Mohr: and using the Miss mta data amputation method we can produce a complete PCA plot of all of those variables.
Rachel Mohr: and doing a multiple amputation, where we refill in the missing values 200 times to see what the differences in the results.
Rachel Mohr: That variance resulting from those 200 different iterations is shown here and we can see that the directions of the two principal components are.
Rachel Mohr: fluctuating slightly, but they're relatively constant in the direction that they should be going in which suggests that, even though we're filling in a lot of missing values with estimated values it's not changing the results of our PCA factors.
Rachel Mohr: And we can also look at between the different variables, which ones have more variants usually as a result of them having more missing values.
Rachel Mohr: So worldwide is one that has very few missing values, so it has a very small difference between the multiple amputations, of the missing data so that's something that we look at in the background kind of for each of these analyses we're impeding data.
Rachel Mohr: But the results here are that the first principle component has a lot of vectors stacked up relating to the size of the Shell, with a secondary principal component relating to the number of two vehicles, so the ornamentation of the individual.
Rachel Mohr: The next step in this process is to use the nb cost package to determine the optimal number of clusters.
Rachel Mohr: Of sort of different morphology is that might be present and statistically valid here so running 30 different types of clustering indices, the most frequent suggested number of clusters is three so we can split up our data into three clusters.
Rachel Mohr: So these would be the three distinct morphology as shown with these variables.
Rachel Mohr: plotting radar plots of the three clusters will show scaled mean average values for each of the variables for the clusters, and this is where we can start to convert.
Rachel Mohr: These cluster memberships back into something that's technically meaningful, so we can start to describe what is it that makes cluster three different from cluster to from cluster one.
Rachel Mohr: In this case, the counts of tumor goals aren't changing as much between the three groups, but all of the other variables relating to size are varying significantly.
Rachel Mohr: So using just the raw more for metric measurements is giving us groups based largely on size which may be more related to on to genetic stages in the population, then say species differences so.
Rachel Mohr: We can look at a different set of variables, the ratio variables, which may give us some more information about shape kind of independent of size and this might be more useful.
Rachel Mohr: PCA of this dataset has the strongest principal component relating to the shape of the world, so relatively how wide is the world compared to how tall, it is, and the width of the venture with some minor secondary characters that explain only a small amount of variance.
Rachel Mohr: The recommended number of clusters for the ratio variables is for and produces radar plots with really unique combinations of variables.
Rachel Mohr: And so, by looking at the different levels of each of the different variables here on the radar plots you can start to move these clusters back into a more traditional taxonomic description.
Rachel Mohr: Of these groups, so we could write Descriptions such as the ones here as an example, cluster for is kind of a unique and Member with the status the widest worlds and the widest Center has the most numerous cubicles of all types, relatively envelope with a low rate of expansion.
Rachel Mohr: So the cluster analysis can kind of show us what the main clusters are, and then the radar plots can help us figure out what the actual morphological characteristics of each of those clusters is.
Rachel Mohr: Just as kind of a side investigation into how much are missing values in the data amputation here is affecting our results.
Rachel Mohr: I took just a slightly smaller data set representing 73 of the best preserved plastic history specimens that I measured, they still have some missing data that had to be imputed but the results were generally similar between.
Rachel Mohr: The previous example that I just showed you so the principal component is controlled by the same variables, the only differences here we're recommending three clusters, instead of four but that's probably just due to this cluster for in the last example only.
Rachel Mohr: represented for individuals, one of them most likely being one of the very, very large specimens in this collection.
Rachel Mohr: And if we examine the morphological differences between these clusters, based on the radar plots.
Rachel Mohr: me a tightness of coiling as relatively similar between all three groups because that's kind of the vertical variation here in these clusters and then the other variables.
Rachel Mohr: Are kind of all scaling together and based on some linear mix modeling that i've been.
Rachel Mohr: experimenting with a little bit it's possible that some of these shape variables actually may correspond to size to some degree over.
Rachel Mohr: Individual specimen so throughout a class and testers individual lifestyle lifespan they may become over time, more compressed or less compressed as they move through different onto genetic forms.
Rachel Mohr: So the last PCA analysis that i'd like to show you today tries to attack this problem of different onto genetic stages.
Rachel Mohr: by looking at a data set that represents only measurements taken at a world height of near 35 millimeters so this would in theory represent individuals all at the same onto kinetic moment in their life.
Rachel Mohr: and controlling for that ontogeny we do still get a similar spread on the first principle component axis, where the shape of the world and the width of the venture, and the number of cubicles are shown as some of the most important features.
Rachel Mohr: Most notably, here, though we get to really distinct clusters that are quite different from each other.
Rachel Mohr: And if we look at the variables in the PCA and the differences in the radar plots we can find some examples of what is actually making these two clusters different from each other.
Rachel Mohr: Some really great example and Members that belong to each of these clusters are shown here, so one of the difference here is.
Rachel Mohr: We have a much narrower world with in cluster one than cluster to So you can see, the overall shape of the world here as much stouter then, this one is much narrower, the other main difference, would be a narrower Venter here and fewer to rickles.
Rachel Mohr: And if we look at these two specimens from another angle here this shadowy area is the very narrow tabulate venture, and here we have a wider Venter.
Rachel Mohr: And some two vehicles, whereas the specimen had much smoother flanks without that ornamentation.
Rachel Mohr: So in this example, at a certain like standard on to genetic stage we have these very to clear populations of different shapes different styles of orientation.
Rachel Mohr: So as a conclusion or summary of where we're at so far in this project.
Rachel Mohr: While there may be as many as eight specimens or species of this genius reported in Alabama previously it's possible that this is a bit over split.
Rachel Mohr: Because our cluster analyses consistently recommend two to four clusters, regardless of the combination of included variables or measurements.
Rachel Mohr: Including a lot more different combinations of variables that i've been able to include in this presentation today, and I think cluster assignments, maybe a useful tool for Objective least sorting.
Rachel Mohr: and members of a traditional series in class and pistorius Shell shapes, this is a really common gravitational series in class and history species that's reported.
Rachel Mohr: Where a population may have a range between these two worlds shapes and the cluster analysis is able to determine.
Rachel Mohr: Without any input from the taxonomist themselves which specimen should belong to each cluster so can maybe help us draw the line between these different morphological types.
Rachel Mohr: or next steps are going to try that third way of including the data manually looking a little bit more at linear mixed models and to kind of attack the question of whether I let it gradualism is that play comparing the populations in Alabama through time.
Rachel Mohr: i'd like to thank the following individuals and institutions for their assistance on this project and, hopefully, we have a minute or two for questions.
Tom Tobin: Thanks Rachel we do have a few and double check that correct about that we actually have one minute for questions if there's a quick question.
Tom Tobin: Think then you've got enough free if you're unsure but thank you and our next.
Tom Tobin: topic technically next poster but it's still talk is from Rosemary gordo and rowan lockwood and I will be sharing that he poster here in just a moment i'm.
Sorry, one second here folks.
Share screen.
Sure got.
Tom Tobin: It you've got the right poster looks correct and i'm going to enlarge this.
Tom Tobin: And let me know if you guys can't hear this or.
Rosemary Guardado (she/her): Are we and cretaceous math.
Tom Tobin: will start that over again hi my name is Rosemary or it auto, and today I will talk about how we end cretaceous mass extinction effective phylogenetic relationships and crass Toledo.
Tom Tobin: There are many studies that have already documented the effects of the cretaceous paley G K big mass extinction on shallow marine invertebrates.
Tom Tobin: However, most of these studies don't actually look at the evolutionary consequences that using a strata graphic or phylogenetic approach.
Tom Tobin: With That being said, during the cretaceous Cranfield bivalves from the US golf course or playing radiated rapidly and which seven general were found prior to the boundary but only three survived the mass extinction.
Tom Tobin: This makes crass until it a useful lineage in order to us to study the effects of the cretaceous pillaging and how it affected evolutionary relationships.
Tom Tobin: In order to study the effects, I had three research goals, the first was to reconstruct my lodge and he of classes holiday focusing on the US office will claim.
Tom Tobin: If you look here at the geologic map on the right, you can see that the area within the white box represents the US coastal plain in which the yellow shadow graphic units represents the Paleo gene and the Green represents.
The cretaceous the red line and between the two, so is the boundary.
My secondary school I had was to identify major cleats within the family and the third goal was to examine the effects of the extinction on genetic patterns punk rock today.
In order to achieve those goals I selected 11 species from crass holiday in order to form my in group and the species within the Ingrid represented time intervals before and after the boundary.
Next, I chose three species of a star today to form my our group and using the 14 species I created a 5454 character data matrix that had characters describing the roof illogical differences.
And some of these characters, including the external ornament the hinge and the outline, so the posterior anterior and ventral margins.
Next analyses were conducted using power, which is a computational phylogenetic program and the analysis also included a branch inbound search branch inbound search with 1000 bootstrap replicates.
Initially power produced nine most parsimonious trees and when I applied a 50% majority rule consensus of the nine trees that resulted in the one tree, which you see here on the left.
And the numbers represent what number what percentage of those nine trees support that parent or that relationship, and so, if you look at.
If you, for example, if you look at bathroom Thomas le foremost and bathroom torrents protects us which i'm circling here with my cursor you can see that 78% of those nine trees, support this relationship.
So, if you look at the philosophy, a little bit closer i'd like to point out to please the first one, I like to point out, which i'm circling here.
Is what I call the bathroom Thomas played because three out of the four bathrooms species in this study descend from a common ancestor the next quarter, like to point out is the one above the bathroom is clean.
And when which this clade contains species from to general crass Intel and Betsy traumas and using that piece of information, we can infer that crass italianate as a whole is pair fanatic.
Using a strata graphic approach I all I took that tree, and please sit next to the time intervals, in which the red dashed line which i'm highlighting here with my cursor represents the KPMG boundary.
And the Cross is next and species indicates extinction and so you can see here that the bathroom is clean.
The bathroom is clean all species after the boundary unfortunately the clay that contains species from crash patella and bath and traumas terminate who right.
At the boundary.
So in conclusion, I found across fatality is paralytic and.
The bathroom is clean all descended from economy, a common ancestor and as we seated after the cretaceous period during mass extinction.
The Clean like contained craps which is from Chris tar and Bradley Thomas unfortunately terminated right at the boundary.
And in the future, I would like to implement a couple of new approaches and one of which being is to use a bayesian analysis, along with the parsimony analysis and by doing so, I would be able to compare the two approaches and see if there are any variations between the results.
Next, I would like to expand a species selection to include those from California, and I would also like to examine another most family that also occurred at the key vg boundary in order to see.
If there any similarities and phylogenetic patterns and evolutionary relationships between credibility and the future mosque family and with That being said, thank you and i'd be happy to take any questions.
Tom Tobin: cool, so we do have some time for questions if anyone has them i'm going to stop sharing because that allows me to see if there's questions, but I can pop that back up if we need to.
Tom Tobin: So if you have questions for me to pop in raise your hand or asking me in the chat.
Tom Tobin: yeah trish.
Patricia Kelley: Is there anything in the Atlantic coastal plain that you could look at I know Atlantic coast clients not nearly as good as the Gulf for this, but is there anything you could look at.
Rosemary Guardado (she/her): yeah, so there are actually species, so, while I was doing some some late, I was looking at the previous literature and everything, there are some species that go into New Jersey.
Rosemary Guardado (she/her): Because that's where the boundary between the quotations in the Paleo gene that's where I think I believe it goes into New Jersey and Maryland.
Rosemary Guardado (she/her): um I don't as of right now, have any specific like species or families, but I could definitely get back to you if you would like to you know send me a little like the podium with your email, I can totally look that up for you.
Patricia Kelley: yeah i'd be interested in hearing.
The great.
Thanks.
Tom Tobin: we've got time for another question or two, there are other.
John Fronimos: So, first of all thank you for really enjoyed that presentation and.
John Fronimos: it's curious to ask you, you had said at the beginning, I believe that there were.
John Fronimos: Three known tax that had survived through the paces Paleo gene event and it looked like in your phylogenetic there were a larger number of ghosts lineages that seem to extend through that and I was curious if you've looked at all in house phenomenon like that might.
John Fronimos: might play a role, and how we interpret the actual i'm magnitude of extinctions if we're not capturing those until we actually see the the father jack analysis.
Rosemary Guardado (she/her): Right that's a good question um so I i'm so the main the primary paper that I used was a monograph Cleveland when guard and she didn't mention that the fossil record was for crass intelligent wasn't as accurate.
Rosemary Guardado (she/her): And everything and so that may also play a role as to like why we see those ghosts lineages and everything.
Rosemary Guardado (she/her): I believe there would be, I believe, like looking at, if I were to expand on this more into the future, I would definitely look at is like the.
Rosemary Guardado (she/her): The mechanisms like as to why we see a wider variety, I don't have the answer right now, but that is definitely something I could I should definitely consider into taking this work forward.
Tom Tobin: have one question in the chat.
Tom Tobin: From dcc do you have do you have any feel for whether they're changing more slowly than other mollusks and then follow up their DNA changes very slowly, at least for main sequence jeans their number of crash crash intelligence in the EC limestone in the Carolina.
Rosemary Guardado (she/her): Right, so do you.
Rosemary Guardado (she/her): High that is a very good question that so unfortunately my city doesn't really focus on the DNA, like those specific DNA.
Rosemary Guardado (she/her): But however, as I said in my presentation, I would like to look at eight different mollusk family and and hopefully by looking at by comparing the differences or how the similarities, I could.
Rosemary Guardado (she/her): probably see if there are any, you know if there are any rapid changes between between the two so, but that is a very good question, and of course I don't have an answer for that as a right now.
Rowan Lockwood (she/her): If I can jump in and follow up I think dcc is David Campbell.
Rowan Lockwood (she/her): So, David I don't.
Rowan Lockwood (she/her): Right now for rosemary's work she's really focused on.
Rowan Lockwood (she/her): The cretaceous and early paley gene material I don't think we've got enough of a time range to really answer your question, if you look at Lynn when guards monograph she hits a little more of the cretaceous than we have.
Rowan Lockwood (she/her): But probably not with enough of a timescale, to be able to get it your question it's it's definitely an interesting it's definitely an interesting question I had not realized that.
Rowan Lockwood (she/her): In terms of DNA they seem to be taking over more slowly, or you can do you mean relative to things like veneer ids are.
DCC: For say a penis there's hardly any difference between a star kids and crescent hill it's much less within CREST appellants.
Rowan Lockwood (she/her): gotcha and so that's and that's notably different than within binaries or pectin ids or Austrians or anything like that you know so.
DCC: they're going slow and DNA has this computer morphology because.
Rowan Lockwood (she/her): I will say that, historically, part of the issue.
Rowan Lockwood (she/her): You know, building off of what rachel's talk was, I think, part of the issue with crass intelligence, is there a bit of a waste basket genus.
Rowan Lockwood (she/her): And there's a lot of morphological variation so it's sort of interesting generally when you have a lot of morphological variation like, for example, Rosemary has see that the dosa.
Rowan Lockwood (she/her): And across its range, which goes, all the way up into the Atlantic.
Rowan Lockwood (she/her): Coastal plain you've got incredible variation just in that single species and so usually with that you would you would think that you'd have some good morphological change strata graphically as well as geographically but I don't think we have information to get at rates yet.
Tom Tobin: After anything there because we're out of time, but y'all can keep chatting via the chat function or not.
Tom Tobin: Our next talk is going to be by lose echoes and we're kind of transitioning now with a good talk to transition us from our mesozoic part to our sentence like section of things.
Tom Tobin: And so we should be moving more or less than to the sentence oh it from here on out Luke can you share your screen.
Tom Tobin: Alright we're seeing.
Louis Zachos: your desk green screen i'm getting a turned on here.
Louis Zachos: Yet.
Tom Tobin: We are good to go.
Louis Zachos: Okay.
Louis Zachos: that's good Alina.
Louis Zachos: Or the order containing the sand dollars it's called the clip the asteroid is developed are divided into three different subgroups that clip yes to rena.
Louis Zachos: The language Nina in the scooter scooter Lino the scooter Lena are the ones we're going to focus on here because they contain a particular anatomical feature called a.
Excuse me here.
Louis Zachos: called a diverticulum or gregory's diverticulum and it's only known from this particular sand dollar group.
Louis Zachos: gregory's diverticulum was first described by Emily Ray Gregory in 1914 one of the early female biologists.
Louis Zachos: Is the sack like Oregon attached to the testing of the animal the diverticulum is shown here expands to fill the channels defined by the internal buttresses of the skeleton or test.
Louis Zachos: Their 10 radio lobes here label by letters and there are five interlace inner radio lobes numbered or label by numbers, while it's actually connected to the digestive tract right here, it is actually functionally separate from the intestine and stomach.
Louis Zachos: With the exception of the astro my PhD all living scooter California San dollars fill the diverticulum with heavy mineral grains that they derive from the substrate.
Louis Zachos: In most cases behaviors restricted to the juvenile forms before they reach sexual maturity, you can see, for this particular sequence of the northern San dollar contract, he has Parma.
Louis Zachos: That it reaches a maximum of somewhere around five millimeters in length, this is about a year, a year and a half an age.
Louis Zachos: Following that, over time, the animals as they grow into adulthood and sexual maturity lose much of their.
Louis Zachos: eventually lose all of the diverticulum and they managed to to eliminate the heavy mineral grains from their bodies, they have you mineral content makes it unnecessary to dissect these little sand dollars to examine the variability and timing and degree of development.
Louis Zachos: We can focus a bright light through the specimens immersed in alcohol and reveals the diverticulum and it's heavy mineral contents.
Louis Zachos: We unfortunately can't do this with fossils, but we have other methods we can use for the fossils.
Louis Zachos: This confirms another one of the interesting aspects of the green filling behavior the animal, not only do they somehow selectively fill the diverticulum with sand grains they're also able to unfilled it.
Louis Zachos: So this implies some form of a pair of static activity in the diverticulum that works in both directions and it's still.
Louis Zachos: Pretty unknown exactly how this works, the diverticulum tissues we've dissected tissues that do not appear to be muscle tissue so we're not really sure how they do this.
Louis Zachos: While the behavior filling the diverticulum was saying is itself isn't itself unusual the sand dollars are also very, very selective in the types of grains they retained in the diverticulum.
Louis Zachos: here's an example from a juvenile and Kofi Michelin I collected a great beach on the Gulf coast of Florida.
Louis Zachos: 80% of the grains inside the animal inside the diverticulum are heavy minerals and are almost entirely eliminated zero con.
Louis Zachos: Heavy minerals themselves makeup less than 1% of the substrate that these animals are found in which is nearly all courts and so their selectivity is is orders of magnitude.
Louis Zachos: Over and above which we find the substrate.
Louis Zachos: An open question is when did gregory's diverticulum originating scutaro form sand dollars and that's basically, what I want to talk about today.
Louis Zachos: The earliest known Stella forms are in the family produce produce fatality.
Louis Zachos: There are 15 formally described species or subspecies of produce good talents in three general, we have here another one of the species problems so.
Louis Zachos: Probably over divided certainly over divided and for the purposes of this talk, I will consolidate this taxonomy by reference to three individual influential in monochromatic claims.
Louis Zachos: These are indicated by the bold names above the tax and the list here, so the three plays or produce nutella Mississippi insists that produce good Tele Conrad I played in a periodic is likely.
Louis Zachos: Three profiles on the on the Left i'm sorry that the images on the Left show pictures of these three major elements of these three clouds and on the right.
Louis Zachos: profiles of in this case Perry arcas lie lie that shows some of the range of profiles that we see in the specimens and a lot of this distinction and species has to do with the subtle changes in profile.
Louis Zachos: The key ancestral character of all the pros who tells is the presence of five genital pores you see an example here this the central apex you can see, the five pores are.
Louis Zachos: By genital pores, these are all associated with individual gonads this implies the ancestral condition of Oscar tell the forms is five genital pores.
Louis Zachos: The genius ios nutella, which is a Pacific warm was contemporaneous with him closely related to produce nutella.
Louis Zachos: Both general are characterized by asymmetric growth in which the place in the posture a lateral inner ramble agra are inflated to some degree.
Louis Zachos: And this results in a test with this greater than the length and generally something of a triangular type outline.
Louis Zachos: This this character also appears to be pleased the morphic so ios patella however differs by the development of some defaecating food groups, so a little bit different structure on the world side.
Louis Zachos: The protests could tell them Mississippi and says clade retains these please the morphic characters, whereas the p Conrad I clade is characterized by equal Axial growth, for which the test length is always greater than or equal to with.
Louis Zachos: The very darkest lie lie clade is characterized additionally by bifurcation of the food groups, but this is a different pattern than the bifurcation we see an ios can tell.
Louis Zachos: US could tell and produce nutella both occur and roxanne middle etc and age enter the earliest occurrence of sand dollars in the western hemisphere.
Louis Zachos: The earliest known clippy asteroid economic goods or paleocene age and they're found in Africa, and this is the presumed source of all the ancestral sand dollars.
Louis Zachos: While likely derived from a common ancestor ios nutella and produce nutella appear to represent and distinct lineages that became endemic to the Pacific and the Atlantic coast respectively.
Louis Zachos: We don't have any real evidence along Pacific coast of South America, but they're used to tell a may have also migrating southward after passing through the Panama straits.
Louis Zachos: practice could tell his range in age from the Middle East, seen through the late using and when extinct at the close of that you've seen or just before the closer that you see.
Louis Zachos: While practice go tell a Mississippi insists in the pros patella Conrad I claims appeared be contemporaneous impart the three plates have very distinct chronological ranges geographically, however, the claims are distributed across the Gulf of Mexico and southern Atlantic coastal planes.
Louis Zachos: To produce nutella Mississippi instance clade was widely distributed and reached high density that many localities it is found in fine grain locking it extends laconic limestone and course sandy by a classic lifestyles somewhat very geographically.
Louis Zachos: The proto scoot telecom read I played with similarly distributed, but it relatively low density is that most localities.
Louis Zachos: is also found in fine grain locking it expands glock in inclined stones and course by a classic limestone so these were not very specific to.
Louis Zachos: substrate faces the Perry arcas lie lie clade was both abundant and widely distributed reaching very high densities many localities, it is also found in fine grain locking it extends curious court sands or morals and hi purity by a classic limestone.
Louis Zachos: Studies of the oldest produce good tell us in this in the species protocol nutella mississippians is found that one most fossils contain settlement internally, they do not have a significant heavy mineral component.
Louis Zachos: Many specimens are filled in part with glock and I pellets but not any greater concentration that we find in the substrate.
Louis Zachos: These pellets are often whether to form iron oxide, which can cause diffuse opaque patterns and X rays, and this is seen in the CT slice here on the left or the.
Louis Zachos: The bright spots appear to be bright heavy minerals, but they're really just a precipitous of arm oxide some hematite Lima night.
Louis Zachos: juveniles of these two clegg's the p Mississippi assists in the pros patella Conrad I glades.
Louis Zachos: juveniles ranging between five and 10 millimeters in length and neither case do they show any retention of heavy mineral fractions.
Louis Zachos: The opaque areas and these X Ray images are just a result of iron oxide precipitation probably from degraded glock nights in some cases, we can see some of the patterns or structures inside, in some cases where you can see the internal.
Louis Zachos: The joy apparatus, so we can see into them they don't appear to be any heavy minerals at all.
Louis Zachos: So where should we find try to find some of these heavy minerals, many of the pros produce could tell is particularly in the periodic is lie lie clade are found in carbonate or carbonate rich sediments.
Louis Zachos: So the first question asked us whether or not these carbonate rich sediments even contain heavy minerals.
Louis Zachos: So we look at all the different faces that we find these the sand dollars in.
Louis Zachos: The cocoa sand and the as information that should Buddha Mississippi and Clark county Mississippi is very court sandy it has a significant heavy mineral component.
Louis Zachos: We see this in the image here in the upper right for this is a heavy mineral extract from the cocoa San we see Dilma night a little bit of magnetite and there's some crystals here of zircons and probably some routine as well.
Louis Zachos: The glock and I read rich settlements that we find in the movies branch formation are represented by this sample from to shove, a creek and yazoo county Mississippi.
Louis Zachos: And it has a minor fraction of court Sam maybe up to 5% courts and but a very small fraction of heavy minerals.
Louis Zachos: The relatively pure carbonates on such as this, found in the coachella limestone and perry Georgia or what we find in Florida.
Louis Zachos: have less than 2% court sand and essentially no heavy minerals whatsoever, so we wanted to focus on the cocoa San.
Louis Zachos: As the most likely environment where we might find where these guys were selecting and retaining heavy minerals.
Louis Zachos: And advantages, the localities around the shoe Buddha also contain abundant and well preserved juvenile periodic Li Li and they're very easy to remove from the cocoa sand so.
Louis Zachos: Everything was kind of a positive really thought I was going to find a heavy minerals and these guys everything pointed us what we find.
Louis Zachos: A small periodic is lie lie all pre sexual maturity reveal very well developed internal buttressing but no heavy minerals.
Louis Zachos: The image here in the upper left is just a photograph or a surface of one of these specimens you can see sand grains inside so they're definitely retaining.
Louis Zachos: A sand grains of the size, we would see and modern sand dollars modern juveniles.
Louis Zachos: And then below here is a 3D reconstruction from CT scans showing the well developed internal structure of buttresses and here we can see some some fragments of the earth aristotle's land and preserved as well.
Louis Zachos: Remaining images or slices from CT computed tomography scans up a row specimens have a few heavy mineral grains some dark spots.
Louis Zachos: But do not retain any of the aristotle's lantern and that implies that all the settlement is post mortem the lower row assessments do retain aristotle's land or, in some cases, almost in place but few, if any, heavy mineral grains.
Louis Zachos: Even in the very smallest specimens less than five millimeters in length we they fail to show any selective retention of heavy minerals.
Louis Zachos: You see a few heavy mineral grains spots these white spots in the specimen here but they're not in the correct size range nor in the correct concentration that we would expect.
Louis Zachos: So, after an exhaustive study of the specimens no evidence has found for selective retention of heavy minerals in any produce cattelan sand dollars, while a negative conclusion appears the earliest ucs patella form sand dollars did not have a particular.
Louis Zachos: Or at least didn't show any heavy mineral retention, the oldest form which you do have evidence is cutie mark menses and the lower miocene or possibly layer latest legacy deposits of Pacific Northwest.
Louis Zachos: If indeed the person who stella's sorry it produce could tell us did not have a diverticulum could that clarify the final genetic relationships among this nutella form sand dollars.
Louis Zachos: If so, any hypothesis must account for the fact that all modern school tell the forums, except for the Eastern hemisphere aster clients have a different to have a different curriculum and selectively fill it with heavy minerals.
Louis Zachos: All modern school tella forums, except for the genius in copy have only for genital pores and only an coby retains the please E of morphic five gentle poor character.
Louis Zachos: The different curriculum is found in key we have from the lower miocene so I had to occur at least by that time and the sand dollars or Lou newell's often called keyhole urgency because the openings in the test appear to comprise a masterful at a group.
Louis Zachos: So we come up with this hypothesis of characters based on these characters and rather than hypothesizing that the indo-pacific as her clipboards.
Louis Zachos: lost the gregory's diverticulum we we hypothesis hypothesized that never had it, so this is essentially derived directly from the stem group.
Louis Zachos: Rather than hypothesizing incur up here last are regained fourth gen poor and then the associated gonads we hypothesize yeah the lineages last that poor.
Louis Zachos: And we hypothesize the presence of Gregor Gregory diverticulum originated in the ancestor some ancestor of all the western hemisphere could telephone exclude telephones.
Louis Zachos: This resulting philology accounts for these characters and can help resolve some of the mysteries and file a geography of these telephone sand dollars.
Louis Zachos: As noted earlier, the first sand dollars appear to have.
Louis Zachos: Our first sand dollars, no in the western hemisphere period of the Open Source from Africa sometime in the middle, etc.
Louis Zachos: And they separated into into endemic groups that use hotels in the Pacific side and produce fruit salads on the Atlantic side, and they must have migrated through the Panama straits to separate these two groups.
Louis Zachos: By the lady who seen us nutella appears to become extinct in the north Pacific region, but does occur now and the Atlantic coast of Argentina, so it must have migrated most likely down the Pacific coast of South America.
Louis Zachos: At same time to produce good tell us have reached their acne in their distribution in North America.
Louis Zachos: By the legacy in the persecuted sand dollars become extinct the replaced in North America by the clip the asterisks and dollars clip yesterday and their forms which lack a diverticulum.
Louis Zachos: A new group it's good to tell the forums represented by hearing GL develops here in South America, probably derived from us nutella.
Louis Zachos: And there is we do find a few fragments from the legacy in a Puerto Rico that we can attribute to ever tell us so it's a group that's very closely related to inherent yellow and this is indicative of now migration up the Atlantic coast of South America.
Louis Zachos: By the miocene screw tell us and dollars reappear in North America and Cuba, from the lowest lower most miocene Oregon is shown to have segregated heavy minerals and that's as soon as possess it diverticulum.
Louis Zachos: So the different curriculum appears to have first originating somewhere in this West Coast group of of sand dollars.
Louis Zachos: The extent genus in copious also known to have a diverticulum for modern forums, most notably the first species of and copia appearing Western North America that are found in the latest miocene and deposits in eastern North America.
Louis Zachos: Ever tella which we found earlier, possibly in Puerto Rico now becomes widespread in the Atlantic and Caribbean coast of North and South America.
Louis Zachos: it's unknown, whether or not ever tell ahead to diverticulum we have never found the juveniles and it's unlikely any adult forms were to retain the grains that we're looking for so that's still an open question.
Louis Zachos: By the pliocene advertiser lineage becomes extinct in both North and South America, the extent genus Molina, which is the common sand dollar we find on the Gulf coast beaches.
Louis Zachos: Is abundant Eastern North America, where it appears to have originated.
Louis Zachos: Since melita and the Dr gina general are also founded the Pacific coast, it must have migrated before the formation of the isthmus of Panama probably sometime in the early pliocene.
Louis Zachos: ECON directness a Boreal species migrated across the Northwest Passage or evidence chosen migrated across the north passage into the Atlantic from the north Pacific.
Louis Zachos: The formation it's a Panama isolated, most of the skill of school tell a foreign foreigners and a glacial ice caps of the pleistocene effectively isolated the Atlantic population and he.
Louis Zachos: He kind of wrapped me us from the Pacific populations with these changes, the distribution of the storyteller forms took home a distinctly modern look.
Louis Zachos: The post pie seems been characterized by migration and school tella forms from the equatorial regions towards the Poles, as well as a westward in Southwestern migration in the Northwest and West Pacific.
Louis Zachos: You kind of acne is today known from the Arctic Ocean off of Alaska from the Northwest territories and the Hudson Bay in Northern Canada and reported occurrences in northern Siberia and is considered to be at least semi polar or possibly large part similar or circumpolar.
Louis Zachos: And to kind of conclude here this nutella form sand dollars are successful modern group of economics and it would appear that possession of the diverticulum and behavior this selected heavy mineral sequestration at a major role in this success.
Louis Zachos: And I would just like to thank these people and institutions that help with this relatively long term study been working to this about 10 years now.
Louis Zachos: and close to that and there's any time for questions, be happy to take a question.
Tom Tobin: Well, thanks for that talk we've got maybe a minute for a quick question if anyone's got one.
Tom Tobin: Well let's.
Tom Tobin: cue up the next top.
Rowan Lockwood (she/her): and ask one quick question, while you're queuing it up.
Rowan Lockwood (she/her): Please do haley That was really interesting thanks for sharing it in terms of the modern.
Rowan Lockwood (she/her): I could noise, when does this does this behavior basically happen as soon as they settle in terms of heavy mineral sort of sequestration, does that happen throughout their entire ontogeny or when they reach adulthood what's the ontogeny look like.
Louis Zachos: It begins as soon as they settle i've collected a movie in modern forums i'm only focused on ECON directness Parma off the coast of maine Bay of fundy.
Louis Zachos: If I specimens that are down at one millimeter in size and it just started to pick up the grains they seem to reach the maximum at around five millimeter length, which they occur in about one years age.
Louis Zachos: And after that they they may retain those and they're growing bigger, so I don't know that they actually released the minerals, but by time they're around 15 to 20 millimeters in size in many specimens that.
Louis Zachos: They have no mineral grains in them whatsoever and the organs completely resolved certainly by time to reach sexual maturity all the spaces filled in with gonads, and all this is completely gone got it all right.
Rowan Lockwood (she/her): Thanks very much.
Tom Tobin: awesome Thank you alright, so our next talk is going to be from.
Tom Tobin: David Campbell who has the unique.
Tom Tobin: position of being the only person who got on top of their stuff early enough to record their talk and send it in so i'm going to be playing a video from.
Tom Tobin: My computer, so let me know if there's any audio issues and we can pause and figure those things out but it be tested earlier and I think you should work fine.
Tom Tobin: So let me get that going.
Tom Tobin: be able to see the video now.
Tom Tobin: turn up the sound a little bit and go.
Thank you.
sense, and so the potential problems and hopefully your way forward to dealing with this emphasizing data from coastal plain here in the carolinas but.
Looking at other examples as well.
Increasingly analyses relate to theological Dana rely on large online day sense often aggregate from a variety of sources.
Saying looking at the evolutionary trends within a group or across texts parents say of extinction Origination global comparisons different regions.
very widely used in the calibration of molecular clock now scenes, but there are a number of potential problems that need to be taken into account.
When it's just the basic identity of the database is it trying to uncritically compile all available data, and let the user decide what's actually reliable out event, or is it doing the critical analysis itself making corrections and updates.
Also, where does it stand is this a work in progress.
Or is it considered to be relatively complete.
This information needs to be it if I clearly for a particular database, so that the user knows what to think about the information there.
Even uncritical compilation requires knowledge workers to not make new mistakes as they're putting the compilation together and.
Also to new what are key places to find data, whether it's published or unpublished.
course if you're doing a critical assessment, then you need a lot more knowledge input to make those judgments and identify what's incorrect what is sound.
How complete are the databases.
there's still quite a lot of publications and have not made their way into the current online databases.
And then there's all the unpublished material I studied by marcia all found that quite a lot of West Coast soon as local account he's had not been document in the published literature, but were found in museum collections, for example.
berlet all likewise highlight the challenges, due to the limits of the databases and advocate that any analysis should consult with a paleontologist to assess the data before assuming that you can just go on with the analysis.
On my clients, we find a number of gaps from our own work homered brand is the major compilation of miles from the piano gene in eastern us and they have close to 3000 texts in there, but under 400 and a half, so far i've been entered into Paleo by date.
Paleo biology database as being in Palmer in brain now it's not the Paleo biology databases basically bad it's the main database that there is so a lobbyist focuses on it.
Another example on level of documentation walk them off formation.
pleistocene in North and South Carolina we've been intensively sampling it and.
Biology database has.
300 some species of mouse reporting.
Published records.
nearly double the total number of miles and have significantly more in some groups when we add in unpublished collections, the number grows much farther not surprisingly, the micro species tend to be particularly under represented.
In publications and in existing collections.
Are the records accurate.
There are a number of different types of areas that may occur and again looking closely at welcome all records refined that we have on the order of 30 to 40% errors in the databases that we examined.
There, a variety of different possible types of air behind this some of these are pretty straightforward to handle others, there are a couple of weird.
We don't know what this is supposed to be.
One particular source of confusion.
homonyms.
computer programs tend to assume that a name that apparently matches another must be the same thing and not necessarily.
And so we have confusion of things have very different ages defined as supposedly the same.
or from opposite parts of the world.
And, in some cases, these errors have lend to wrong calibrations for example of molecular clock papers.
Another example.
My entire life.
And secondly, if life has range maps for based species does not recognize that they are homonyms and being a problem and the reins maps are swapped.
discover life.
picture here is an actual cash pod graphics and that's what discover life says it looks like Well that is graph us but it's the lichen not the gastropods.
One specific problem in Paleo biology database is that a lot of data.
have been injured relatively generically.
But that has been treated as an actual.
valid rank rather than an uncertainty.
For example, a number of things are listed as just guessed Dakota no more specific so just apologize for day.
and
Some of those are appeals, please he owns it actually should be just generic guest upon apologia day is very much not it is.
A modern.
Land snail quite derived within guests ricotta and should not be, this is a sister texts on, of the other things and listen only as cast ricotta.
lt information from all publications and labels is another potential significant problem.
Recent things have often been described before the fossils in so especially going back before that later 1800 and too often see the recent genius or family name being applied to much older things, maybe aren't even too closely related.
As an extreme case carpe diem.
crew carpe diem is nia gene eastern Atlantic, but it is listed in Pillar by database has going back to the automation.
g beef goes further defines the automation record as a synonym of a recent species know it's a homonym not a synonym.
The automation when it's actually your roster, not even a bivalve and certainly not closely related to Korean.
And that has been used in and watch a clock calibration that i've seen.
pectin scallop another.
example of name that's been us wastebasket far beyond their we arrange.
Sometimes in your mind publication may throw in some old data for completion that needs to be recognized that such and not treated as a modern update.
stratigraphy.
With the development of extensive use of playing time micro fossils we had greatly improved calibration of the correlations between continents.
which show that the traditional upper miocene of the southeastern us was actually pliocene but that's been 50 years and you still see sources, including some of the online databases that are supposedly up to date.
Calling these things missing rather than pliocene.
Sometimes there's been incorrect parsing of a source text, for example, the genius assignments in Campbell 1995 on the city limestone funnel have been attributed in some cases to the author of the original species, not to kimball.
This is the odd one Conference, because they use a genius name described in 1930 when counted written 1833 or listing subspecies as being described by the author of the species.
Having appropriate accountability is often a challenge.
making things reliable requires checking by natural workers but they've got their own things to do, commonly what's going to happen is somebody is trying to look up one particular thing happens on a database record and that's wrong.
not going to have time to go through and do a lot about it, but if they can send a quick message flagging this thing you need to fix this.
Then, that information has been conveyed to the database and they're able to do something about it.
A lot of databases, do not have any convenient way to report, a problem you have to hunt around and sometimes you don't find anything.
And when something is reporting.
There may not be anybody doing anything about it, it can be very slow.
it's possible to do things better worms is a good example major database that has quite good responsiveness it's not hard to find the address to send in something and they respond quickly to it.
Another aspect of accountability is who's responsible when things have been aggregated.
And big databases that draws on others and.
When you out there's a problem, and sometimes they say oh go bother them.
At all one to do that, you have to actually figure out how to track down what the source was which is not always so obvious, and if you take that much trouble.
Sometimes, what you find is the source was perfectly fine it's the big guy aggregating that made the mistake wrongly putting things together.
So what are these problems serious.
Well, it depends on what you're doing with the data and it's going to be variation different.
Tax a different localities have different degrees of problems.
These areas are often going to be outliers now if you watch out for outliers, then you can potentially identify what suspect and have.
Improved data to work with.
But if you're relying on something that reports, the extremes, as the total.
You may be in trouble.
For example, much like your clock typically what they're doing is what is the oldest age for tax on X.
And stanton POPs, and all this page and go off and use it in the other actually tracking down and finding out whether that's a sound record yeah the oldest ages often some wastebasket name from 100 years from 200 years ago and.
not actually at all reliable.
What can we do about this.
Building reliable data will require support for the expertise necessary to make sure that information is credible.
and similarly in funding, often what's been done is here's money for projects to come up with cool things can figure out based on these data.
But there's no funding for checking if the data are good enough to bother doing all these analyses with.
So there definitely needs to be better distribution of support to go for the generation in verification of these data.
Not just.
Using databases assuming everything's good.
I likewise needs to be clear responsibility for the corrections and updates having.
Things in charge what database is handling what and how does it interact between different sources.
To go back to the question of who might be afraid of bad big data.
If we make these types of improvements, we can make sure that our databases are full of hot air and the future state out of hot water, thank you.
Here are some of the being references cited.
Tom Tobin: awesome, thank you for that talk David that was great.
Tom Tobin: We do have a couple minutes for questions.
Tom Tobin: There are a couple in the chat.
Tom Tobin: So rowan asked, have you thought about simply fixing these errors and databases yourself, most of these databases are based on Community members, improving the accuracy of the data.
DCC: So that's definitely an important component of how you do things things can sometimes it's pretty straightforward sometimes it's not so easy there's also the challenge of well.
DCC: And, in the midst of trying to do a lot of other things don't really have time to go through this systematically.
DCC: If there were some way of saying hey here's an issue.
DCC: Then, that can be on the list if there's somebody at the other end been respond to it so it's definitely something be interested in.
DCC: going to find time for a challenge for all of us doing anything as an issue there and also helping fan bases, make it easier.
DCC: To do this, obviously you don't want the just anybody changes anything but, having an easy way to input something, and hopefully have the back and forth to check it and work on it.
DCC: Also, again, it depends how you're using it.
DCC: kind of paying attention, not just uncritically assume everything's great.
Rowan Lockwood (she/her): And I think if you're interested and David there paleontology database they they obviously don't have the staffing or the funding to be able to.
Rowan Lockwood (she/her): You know fix these errors of themselves, but they could assign you with a partner and that partner can walk you through the process, they they've simplified the process for fixing data.
Rowan Lockwood (she/her): it's now super teachable to undergrads and master students, so I feel with a partner, you know it should be relatively straightforward to go in there and and and make some of those adjustments.
Tom Tobin: good time for one more question probably.
Rindsberg, Andrew: yeah.
Rindsberg, Andrew: All right, suppose you want to correct all those carboniferous pectin that don't belong to Jesus pectin.
Rindsberg, Andrew: What happens in the database, if you just say it's not pectin.
Rindsberg, Andrew: And don't know what the correct gina's name is.
Rowan Lockwood (she/her): yeah so you can put in a taxonomic revision and you'd have to.
Rowan Lockwood (she/her): You know, for someone who wasn't a scallop worker wouldn't be allowed to do it, they wouldn't basically be able to get permission to do it, but the scallop worker would put it in.
Rowan Lockwood (she/her): And then those particular organisms until they get revised to an actual genius they just wouldn't be part of that that analysis they wouldn't pop up in an analysis that you're using for molecular clock or that sort of thing.
Rindsberg, Andrew: That would be an improvement.
DCC: yeah having a.
DCC: This is a moon category is something that.
DCC: Is a value in me i'm sure if it's in person interview you.
DCC: realize the possibilities as well.
Tom Tobin: cool we got time for maybe one more quick question actually I think I take that back it's just changed over the minute so we're out of time, thank you for that and now we're going to have.
Tom Tobin: Make sure I get things correct here in order our next speaker is calling Norton who have a poster so again i'll be playing that poster will be about five minutes and then we'll have some time for questions after that so give me one moment to get that rolling.
Tom Tobin: Right to this threat poster is and calling you wanted the screen down here in large correct.
Colleen Norton: yeah Thank you.
Tom Tobin: All right, i'm gonna go in here.
My name is colleen and for my research I analyze the size and age structure of oysters in the lower Chesapeake.
First i'd like to give some background about this project because last year virginica or the eastern oyster are very important organisms in the Chesapeake bay.
Unfortunately, the populations have declined significantly so it's very important that we study these organisms to try to determine the extent to which humans are impacting their populations.
Size an H are two of the most important population demographics for Eastern oysters, and this is because there are many oyster population parameters that need a structure as an input.
And because agents I structure information are necessary and informing restoration practices, this is what my research will focus on these two population demographics.
For my research project I had two main objectives, the first was to determine the relationship between shelling than age at a restored modern oyster reef called beans creek.
And the second was to compare this beans Greek size and age structure to the size and age structure of a fossil a serif.
David Schwimmer: The study area for my research was beings creek which is located in lower Chesapeake Bay, as you can see, on this inset map to the right, this is a sanctuary reef and it has not been harvested for seven years.
Oh now described some of my experimental design and methods, the sampling for this project was done in October 2020 and once the oysters were acquired I took measurements for Shell link.
Next I estimated the age using growth banding to to to do this, I took the Left velveeta oyster and cut it at the hinge cross section using a title so.
Next, I would Polish the hinge and then count the number of growth bands, the great bands on these hinges represent some winter temperatures.
And the white bands are summers are disturbance events when counting these bands you count only the thick grey bands, the asymptote out toward the bottom of the hinch So if you follow my cursor you can see me trace one of these bands.
After compiling the show lengthen age data I analyze it in four ways first I looked at the distribution of show length in live in dead oysters.
I then plotted the age versus length for growth banded subset of 72 oysters.
Next I use this agent length analysis to derive an equation that was applied to a random sample from the full population of oysters and this random sample was plotted for a link that age analysis and then a curve for this plot was fitted using the von birdland fee growth model.
Lastly, I compared the modern length of age data to that of fossil wasters and the data for fossil wasters were compiled from a previous study.
There are a few key results to take away from this study, these are histograms showing the show length distributions for live and dead oysters.
As you can see shelling is on the X axis and frequency is on the y axis, and please note the difference in the maximum values of the y axes.
These graphs show that there's an abundance of live oysters at this reef but the frequency of oysters greater than 100 millimeters is quite small also there's a low overall percentage of dead oysters and these results, provide evidence that this is a healthy reef system.
Next, I want to discuss the length of age results for modern and fossil reefs ages in years on the X axis and Shell length is in millimeters on the y axis.
The Green triangles represent fossils specimens and the blue dots are modern specimens.
What we can draw from comparing these two populations is that fossil oysters grew older and larger than modern oysters do half of the growth rate represented by this line for modern oysters is higher than that of fossil oysters.
So why is this the case, I want to discuss some of the possible explanations for these observations.
One possible explanation is that the increase in sedimentation rates throughout the bay, has resulted in a selection for oysters with higher growth rates, because oysters will die if they're buried by settlement.
Also nutrient loading has increased in the Bay and most molluscs growth rates will increase under higher nutrient conditions so higher nutrient conditions may select for higher growth rates.
Lastly, harvest pressures over the last few centuries, maybe influencing the trends that we see in these results.
Today, the minimum size of which you can harvest an oyster 76 millimeters, and this means that humans preferentially harvest only larger oysters.
general trends and sanctuary reefs compared to harvest reefs show that there's an age and size truncation and harvest reefs.
But these harvest pressures have existed for a long time, so they may be influencing the bay as a whole, not just the singular harvest reefs.
Future ratio research should be done to quantify how these human influences have exerted artificial selection on populations and in the Bay as a whole with that I will conclude my presentation Thank you so much, and I will now take any questions.
Tom Tobin: awesome Thank you stop sharing and see what's going on with pop it open, if you do we've got a few minutes for questions if there are any.
Tom Tobin: i'll ask a.
Joshua: quick question yeah oh.
Joshua: Sorry, no go ahead, my my apologies, my video is.
Joshua: Go ahead.
Tom Tobin: i'm asked quick one, then, which is how certain are you that the growth fans that you're identifying as a different Shell, particularly different Shell texture that are actually annual.
Colleen Norton: um yes so that's a good question um previous research has been done on this and the paper that I used as zoom it at all from 2019 and what they found is that the growth bands when they did square a chronology on these growth bands they found that.
Colleen Norton: delta 18 values varied, at the same.
Colleen Norton: Time like the Delta, it would peak peak and it would correlate with the great girls fans and then the non peaks in delta 18 value would correlate with white growth fans.
Colleen Norton: So they found that it's a strong correlation and they were fairly certain that this is the case in fossil oysters and because the there's the same morphology in modern oysters today it's we're pretty certain but further research will be done to kind of confirm that to.
Tom Tobin: joshua first and i'll get back over to you Patricia second yeah.
Joshua: Thank you um yeah I just had a quick question, I may have missed this in your presentation, but so you said use modern ocean from the Chesapeake area use the.
Joshua: The.
Joshua: Sorry camera this piece i'll top my head, but it's the same ones we have here, I live on the Gulf coast right now and grew up here so it's basically the same motion for the fossils that he is for analog what what age data those just out of curiosity.
Colleen Norton: So those were from the place to seen and they.
range.
Colleen Norton: Think 250,000 to 400,000 years in age yeah.
Joshua: So, with the fossil ones, I personally study fossil was Teresa mainly the lake cretaceous nearly Paleo again.
Joshua: So completely different but i'm just curious because a while a lot of like you mentioned your presentation.
Joshua: is similar to what I see as far as trends goes for is sediment in nutrient input into the environment, we have those larger oysters are you seeing the same thing with the pleistocene ones that you're observing and fossil record.
Colleen Norton: i'm sorry, can you repeat that.
Joshua: i'm not sure I see yeah sorry so with the larger or sure you're seeing are are you seeing a trend with their larger and fossil record as opposed to today.
Joshua: Because of in like I know you mentioned the answer but genetic factor with modern oysters but with the input sediment and increase nutrient input is that a big factor with the fossil ones or is that just something that.
Joshua: um there's something.
Colleen Norton: yeah i'm not sure I think that's that's a good question and um yeah my hypotheses for like sedimentation rates and nutrient loading were mainly focused on why the modern oysters might look different than the oysters but i'm not sure why this or if that impacted fossil oysters.
Joshua: Did that well.
Joshua: Okay yeah no I said I was curious because that I started from way old nose and the trends are really similar which kind of doesn't surprise me, yes, and like I said also grew along the Gulf coast, so this is pretty cool getting to see something that's still here today.
Tom Tobin: we're running pretty out of time, and of course you've got a question, maybe we can hold that have a next posters that oysters as well, potentially available oyster discussion after the next poster to be our last one.
Patricia Kelley: Or, I could put it in the chat.
Tom Tobin: Or you can put in the show yeah either way awesome Thank you very much like set our next and final presentation for the session is posted by Catherine de mckinney which I will queue up here and same deal for you, we want the bottom screen enlarge correct.
Tom Tobin: And then we'll have a little bit of time afterwards to.
Tom Tobin: chat around and people want to stick around I don't know when they if they zoom meeting gets killed, but hopefully it won't be.
Tom Tobin: All right, let's close that and share screen with this one is the correct one yes cool large that.
hello, my name is katie mckinney and today i'm going to be presenting about my research in New York river in Virginia.
The York river is a main tributary to the Chesapeake bay and houses, Chris Austria virginica the eastern oyster.
oysters play a vital role and cosine ecosystems and improved water quality and the health of the surrounding environment.
But over the past two centuries, the population of course Austria and Virginia waters has sharply declined to do to overharvesting and disease.
The species abundance today is about 1% of historic levels and as a result, or history frustration, has become a common practice in the Bay to help bring back the historic numbers.
location for this study lives at the mouth of delegates creek a tributary of the York river the reef itself was constructed in 1999 and receded and.
And this figure, you can see filebeat creek delegates creek reef in New York river.
This particular refills never been mapped or samples because of its difficulty and location, the reef is not fully exposed at low tide but it's not deep enough to map and sample with the biotechnology.
Here we introduce a new technology for monitoring reef such as delegates create.
The research goals of this study, where, therefore, to one produce a high resolution brass your profile of foggy it's great to understand what we were sampling and to quantitatively assess the performance of this reef stratified random sampling.
to master if we use what's called an acoustic doppler current profile or or a tcp and in our tk base stations apply by grace massey and the Virginia Institute of Marine Science.
You can see the tcp in this figure right here, and this is the Arctic a base station, the Arctic a base station was placed on the end of pediment spit and delivered accurate GPS location, so the Ad cpu while I was performing transcend.
The tcp itself was remote control from the boat and ran transact lines across the reef and delivered soundings to an onboard computer the resulting profile can be seen in the middle of this poster.
The figure on the left is the roster output of the profile the purple the purple being the highest relief and the red being the lowest.
The purple and blue are my sampling areas, the transcripts created from the profile were used to create the figure on the right and our pro which delineated my sampling shadow by depth and created my sampling points.
Here you can see, this data labeled a the shallow stratum denoted in purple on the left and be the deep shot in the dark blue on the left.
field sampling occurred and December of 2020 in January 2021 14 samples were taken nine from a and five from be.
A quarter square meter quadro was placed underwater at the specified GPS location and all oysters within that square where excavated and bag for processing.
samples rid of island alive oysters oysters and discard length with live volume and dry weight were measured in the lab it them's and analysis was performed using are.
Moving on to my results and discussion the reef itself does not follow a typical pattern naturally it's usually follow a title pattern and are long and straight.
But you can see, in both of the reef figures therefore sub sections of delegates creek created during construction 123.
And four and evidence shows the original constructed area of the reef be much larger than what we're looking at here do to increase sedimentation.
Preliminary results show thought gates creek reef being a healthy successful roof on this population structure instagram we have Shell high on the X axis and frequency on the y axis live oysters are denoted and grey and dead in black.
Multiple age classes of oysters were found through sampling and you can see the cut off between juvenile and adult was just right around 25 millimeters.
On average 50 oysters per square meter were found on the chalice data and three oysters were found per square meter on the deep stratum the biomass on delegates creek it on delegates grief grief is high on the second graph we have.
shelling on the X axis and dry weight on the y axis and this red box here is to noting oysters larger than legal harvest size, which is always greater than 76 millimeters.
This is most likely due to the location of the reef and lack of poaching and ideal nutrient supply due to the location at the intersection of New York river and focus creek.
All portions portions of the reef how successful investors suggesting adequate nutrients apply an optimal history environmental conditions.
In conclusion, we are able to accurately not this refusing new advanced technology and offer potentially unique methods for sampling and monitoring reefs comparable the floodgates CREA CREA.
prelim preliminary results show this location as a functional oyster habitat and the presence of multiple age classes in high density shallow areas could make this location promising for future restoration.
future work will include designating bottom type in order to develop a habitat suitability index this area to better analyze this location and proximity to the bay, thank you for your time and i'm happy to answer any questions.
Tom Tobin: All right, thank you.
Tom Tobin: there's been something going on to Chapter if it's a discussion from the previous one.
Tom Tobin: didn't have any questions.
Tom Tobin: For Kate.
Tom Tobin: The author quick question.
Tom Tobin: reflects my ignorance about modern oyster recent things of it, are you mentioned, they often are sort of aligned with the tides.
Tom Tobin: Is that correct Okay, and so these blogs, are these bob's just literally like pay they went out and dumps and stuff in these spots like that why we were seeing that shaped still.
Kate Dean-McKinney (she/her): yeah so those four sections of the reef that I was talking about in the presentation, those were created during the construction so.
Kate Dean-McKinney (she/her): Literally what you're talking about is they just went out and they just dumped those.
Kate Dean-McKinney (she/her): The Shell into that area and that's what we're looking at and what we don't know I mean we know that the area of that reef was bigger when they when they see did that.
Kate Dean-McKinney (she/her): In 1999 and what we don't know is what exactly that looks like but yeah it's pretty comparable to what we're looking at their.
Kate Dean-McKinney (she/her): Well, if.
Tom Tobin: This persists long enough, will we we lose that original delineation or is it going to kind of preserve that because they want to be at a certain height.
Kate Dean-McKinney (she/her): yeah so because of the way, though it's just like to settle that that we're going to probably keep seeing that same trend happening.
Kate Dean-McKinney (she/her): I don't know how long it will take before the sedimentation takes over and we lose that but that's kind of the trends that we're seeing happen.
Tom Tobin: Your question from Patricia.
Patricia Kelley: hi, thank you for a nice time, you may have said this, I was typing a question to your colleague, but I was wondering if you could talk a little bit about how what factors go into the hs I would almost consider.
Kate Dean-McKinney (she/her): yeah so I actually in my object that was the goal of this project, originally was to create.
Kate Dean-McKinney (she/her): A habitat suitability index and but that actually is beyond the scope of what i'm doing right now, but that is going to be the future work.
Kate Dean-McKinney (she/her): But within that it's going to be the bottom type which we don't yet know we saw a little bit of that through sampling but classifying bottom type within the stratum.
Kate Dean-McKinney (she/her): depth and salinity and then just looking at the area in general, so there's already been a habitat stability index for Chris Ostia in the Great Wall conoco river in Virginia, but not yet for the York river, so this was just add to that.
Patricia Kelley: Thank you.
Tom Tobin: Oh good time for another question, too.
DCC: Based on what you've seen probably on tom's question, what do you recommend that they design briefs differently in the future, does the kind of just dump it there seem to have not done as well as it could have.
Kate Dean-McKinney (she/her): Yes, I think um what.
Kate Dean-McKinney (she/her): That, I think what you're kind of.
DCC: Asking is.
Kate Dean-McKinney (she/her): is why that doesn't matter where we're doing this or kind of how we're monitoring that.
Kate Dean-McKinney (she/her): I think the short answer is it's not very economical to just go and dump Shell wherever and that's part of the reason why we would like to develop a habitat suitability index, to be able to optimize where these oysters are going to be restored.
Kate Dean-McKinney (she/her): So, in short, that's not recommended they did do some preliminary research in cell gates and noted that it was it did have some optimal moisture conditions for restoration so it's not entirely.
Kate Dean-McKinney (she/her): Based on just absolutely no research but yeah I don't I don't necessarily recommend them just dumping over the side.
Kate Dean-McKinney (she/her): Any other questions.
Tom Tobin: cool well, if not thank you all for attending i'll keep the zoom open for a little while people want to chat at all, but that is our last presentation, so thank you for our journey from basically the whole fan of result if you've been here the whole whole afternoon.
Tom Tobin: And I hope that the next se GSA that I can organize an actual get together for the Paleo folks in person, hopefully, so if you're not on my.
Tom Tobin: If you didn't haven't received emails from me over the last year about Southeast Asia society things and you want to be notified in the future, please email me i'll put my email in the chat.
Tom Tobin: We can just look me up on the University of Alabama you can find me and i'll get you on that list so you'll find out if we do something at the next se GSA.
Tom Tobin: If not, thank you all, and thank you to my co chairs.
Tom Tobin: And yeah.
Tom Tobin: Second.
Rowan Lockwood (she/her): Let me just jump in and give another round of applause for all the speakers, but also for the co chairs for organizing this and dealing with all of the zoom stuff today, so if everyone can unmute and give everybody a quick round of applause, I think that would be great.
Rindsberg, Andrew: Also, a note that are currently 33 participants and that's a lot for or something past 537 even central time 630 Eastern time.
Rindsberg, Andrew: Thank you for staying.
cool.
Tom Tobin: well.
Rindsberg, Andrew: I feel like the Brady bunch yeah.
Tom Tobin: also wants to.
Rindsberg, Andrew: Patricia hi Tom.
Tom Tobin: All those.
Tom Tobin: who presented posters like that's really hard to do a five minute poster get all of your covered in that.
Tom Tobin: it's normally posters going a little bit different than top like yours, I just get like a five minute presentation that's really hard so well done to everyone, did the poster So those are uniquely challenging in this virtual space.
Tom Tobin: fun for me to see those things to.
Tom Tobin: put my email down in the chat if you have that open if you if you aren't on the list and getting harassed by don't I personally like three emails a year, so you won't get barraged but.
Tom Tobin: You haven't got an email with here, let me know.
Rowan Lockwood (she/her): Oh, and Tom Michael was just asking in the chat if there is a southeast paley society meeting for officers or anything like that I don't think there's anything this this time around right.
No.
Tom Tobin: that's my I didn't see anything in the chat room is asking you.
Rindsberg, Andrew: I thought the south southeast Paleo society was mostly or Oh, are you talking about in southeastern section.
Rindsberg, Andrew: yo okay.
Rindsberg, Andrew: And I think we're is a southeastern Paleo society but it's mostly vertebrates.
Tom Tobin: yeah sorry I just think it.
Tom Tobin: Just to be clear i'm talking about the southeastern section of the Paleo society as a whole, where we usually get together for for people don't know we usually have an in person gathering at.
Tom Tobin: What we haven't been the last one is fully cancel last year's as bleak Angela this one virtual but next year we'll have something hopefully.
Rindsberg, Andrew: Good food and beer yeah.
Tom Tobin: I think we might have to be a joint.
Tom Tobin: Say next year isn't it.
Tom Tobin: Like we might have a joint section meeting next year I can't remember.
Tom Tobin: The northeast really that's 20 2030 I can't remember.
Tom Tobin: But that might be fun to meet those people as well.
Patricia Kelley: And we used to turn over officers, every year, you know back in the 80s when when the section was just starting.
Patricia Kelley: But I think in more recent years, people have held on to the position of chair her a little bit longer a year or two to two or three years and I don't think we've worked Tom hard enough yet for him to develop this position.
Tom Tobin: never really done anything, yet I took it over from Michelle a couple years ago.
Tom Tobin: Where she's like hey Tom to Charlie on everything went downhill at that point, so I hope it's not my fault but.
Tom Tobin: It looks of it is not your fault.
Tom Tobin: Next year 2022 will be a joint session with the North central section and Cincinnati so talk I don't know offhand who this the north central Paleo REP is but we're probably have a joint Paleo society meeting with them.
Tom Tobin: To be fun and since then he's got some cool Paleo and as well, so expect that we can call field trips and.
Rowan Lockwood (she/her): things of that nature anomaly cool.
Rowan Lockwood (she/her): All right, i'm going to take off, it was really great to see everybody I miss you all it's not the same on zoom joshua let me know if you want to talk oysters in more detail i'm very interested in what's happening in the Gulf.
coast.
Rowan Lockwood (she/her): So very.
Rowan Lockwood (she/her): Good touch base with you.
Joshua: Know that's true you know I grew up and live on the Gulf coast, right now, after you know my graduate school career and I have harvest and oysters and i'm very I suppose you could say intimately familiar with the oysters here so.
Joshua: cool to see people are still studying, though.
Rowan Lockwood (she/her): yeah so if you're interested I just I stuck my email address in the chat for you.
Rowan Lockwood (she/her): you're welcome.
Rowan Lockwood (she/her): to drop me a line and but it's really good to see everybody take care stay safe.
Patricia Kelley: Thanks everybody come.