A MULTIPROXY ANALYSIS OF BISON LATIFRONS PALEOECOLOGY DURING THE LATE PLEISTOCENE OF GEORGIA

Bison was widespread across North America during the late Pleistocene, and is still represented by the extant Plains Bison (Bison bison bison) and Wood Bison (B. b. athabascae). The Pleistocene Giant Bison, B. latifrons, is best known from specimens collected across the Great Plains. The species is characterized by extremely long horn-cores and is generally associated with browsing habits in open woodland landscapes. The dentition is identical to the temporally sympatric B. antiquus which appears to have inhabited more open habitats south and west of B. latifrons’ range. In the absence of associated horn-cores, most Late Pleistocene bison fossils collected in the southeast are identified tentatively as Bison sp. Associated horn-core, dental, and postcranial material identified as B. latifrons have been recovered from Clark Quarry near Brunswick, Georgia, and radiocarbon dated to approximately 21,000 YBP. As a result, these fossils provide a unique opportunity to investigate B. latifrons within a high-resolution paleoecological framework. In this study, we use astragalar morphology, mesowear signature, and enamel carbon isotope ratios as proxy indicators of the paleoecology of B. latifrons in Georgia. Although we have a limited number of specimens, astragalar morphology suggests adaptations for open habitats. Mesowear analysis indicates wear patterns consistent with mixed feeding taxa. Carbon isotope ratios also suggest C₃/C₄ mixed feeding, with perhaps 60% C₄ grass consumption. At the time that the fossil fauna accumulated at Clark Quarry, the locality was roughly 100 km from the coast. Biome reconstructions for the area prior to and during the last glacial maximum suggests warm mixed forest characterized by pines, grasses and sedges. The inferred plant community is consistent with a mixed feeding ecology for B. latifrons. In terms of modern analogues, the Giant Bison appears to have been more ecologically similar to the modern Wood Bison than the Plains Bison.