USING EXPERIMENTAL TAPHONOMY TO UNDERSTAND EXCEPTIONAL PRESERVATION IN THE FOSSIL RECORD

Exceptional fossils are found throughout the much of the geologic record and are preserved by many different taphonomic (fossilization) pathways. These pathways involve complex biogeochemical processes that can be difficult for students to understand in a traditional classroom. In order to overcome this in an Advanced Paleontology class we used Wynogradsky columns and taphonomy experiments to visualize these different processes and discuss how they can promote or inhibit fossilization. The Wynogradsky columns demonstrated how different microbial communities will form and develop under different conditions (just sediments, added carbon, added sulfur, and added carbon and sulfur). These were then used when discussing some of the early processes that can occur in sediments prior to fossilization. The students monitored each column once a week, collecting data and photographs in a shared Google spreadsheet. The taphonomy experiments tested the preservation potential of feathers, leaves, shrimp, and mussels, which represent some of the diversity of tissues found in exceptional fossil deposits. The experimental conditions involved burying the different organisms in 4 different sediment types and artificial seawater, mimicking some of the different sediment types in which exceptional fossils are found. These data were also shared in a Google spreadsheet for comparison of different sediment conditions and tissue type. Results from the experiments and the continued observations of the Wynogradsky columns throughout the semester illustrated the many processes that occur within the sediments, and how rare the fossilization process is. These also helped the students make better scientific observations and envision possible conditions that may promote the preservation of exceptional fossils in the various deposits discussed in class.