Start |Grid View | Author Index | View Uploaded Presentations | Meeting Information

GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 209-4
Presentation Time: 2:15 PM

STABILITY OF DENTAL MESOWEAR SCORES THROUGHOUT THE LATE PLEISTOCENE IN LARGE UNGULATES FROM RANCHO LA BREA


COHEN, Joshua E.1, DESANTIS, Larisa R.G.2, LINDSEY, Emily3, MEACHEN, Julie4, O'KEEFE, F. Robin5, SOUTHON, John6 and BINDER, Wendy J.1, (1)Department of Biology, Loyola Marymount University, 1 Loyola Maryomount University Dr, Los Angeles, CA 90045, (2)Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, (3)La Brea Tar Pits and Museum, 5801 Wilshire Blvd., Los Angeles, CA 90036, (4)Anatomy Department, Des Moines University, Des Moines, IA 50312, (5)Department of Biology, Marshall University, Huntington, WV 25755, (6)Earth System Science, University of California, B321 Croul Hall, Irvine, CA 92697

The Rancho La Brea locality (California, USA) is world famous for its asphalt deposits that trapped late Pleistocene megafauna over the last 50,000 years. This wealth of paleontological data allows for detailed investigation into paleoecological changes through the last glacial maximum into the Holocene. Here, we examined the mesowear of Bison antiquus, Equus occidentalis, and Camelops hesternus from five pits spanning the latest Pleistocene (~40–12 Ka): pits 77, 91, 13, 3, and 61/67. Five observers scored mesowear for each specimen and mesowear numerical scores (MNS) were compared between pits and taxa, and against a modern dataset of grazers and browsers. Mesowear values of each taxon examined did not differ between pits (all p-values >0.11). Additionally, E. occidentalis consistently had higher MNS values (mean of 3.8) than both B. antiquus and C. hesternus and was indistinguishable from modern grazers (p=0.19). B. antiquus and C. hesternus MNS values (mean of 1.6 and 1.5, respectively) were consistent with modern browsers (p=0.33 and 0.17, respectively). The values for B. antiquus (all pits combined) differ significantly from those for the modern grazer B. bison (p<0.001). The stability of mesowear signals between pits is in contrast to previous studies that found changes in diet across the late Pleistocene based on microwear and stable enamel isotope dietary proxies. These differences in dietary interpretation may be due to the different signals each proxy represents. Dental mesowear signals reflect abrasives in or on food consumed while dental microwear textures record the textural attributes of food consumed, both representing different amounts of time. Previous studies using age structure and serial enamel isotopes have suggested that B. antiquus migrated into Rancho La Brea yearly, so dental microwear may signal specific diet consumed at Rancho La Brea while dental mesowear may represent feeding behavior at and beyond Rancho La Brea.

Session No. 209

D21. Paleontology: Vertebrate Paleobiology II
Tuesday, 24 September 2019: 1:30 PM-5:30 PM
Room 225AB, North Building (Phoenix Convention Center)
Geological Society of America Abstracts with Programs. Vol. 51, No. 5
doi: 10.1130/abs/2019AM-336642
© Copyright 2019 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.
Back to: D21. Paleontology: Vertebrate Paleobiology II
<< Previous Abstract | Next Abstract >>