Paleoenvironment of the Central Depression of Chiapas, based on stable carbon and oxygen isotopes

Abstract

We inferred the diet of Equus conversidens (three specimens), Cuvieronius hyodon (five specimens), Bison sp., Eremotherium laurillardi, Mammuthus columbi and Panthera atrox (one specimen each) from Rancholabrean fluvio-lacustrine deposits in the Central Depression of Chiapas, using their carbon and oxygen isotopic composition. The environmental conditions prevailing during the Late Pleistocene in the region were also inferred. Our analysis shows that E. conversidens, Bison sp., and M. columbi fed on C4 plants (δ13C: -1.8‰ to -1.0‰), E. laurillardi was a mixer feeder C3/C4 (δ13C: -7.7‰); on the other hand C. hyodon was a largely a C3 plants feeder (δ13C: -9.4‰ to 11.4‰), whereas P. atrox preyed upon C4 herbivores (δ13C: -5.5‰). Our analysis also discloses more arid climate than at present, as well as the presence of grasslands associated to trees.