Southeastern Section–55th Annual Meeting (23–24 March 2006)

Paper No. 1
Presentation Time: 3:05 PM


BAHN, Robert A. and MEAD, Alfred J., Biological and Environmental Sciences, Georgia College and State Univ, Milledgeville, GA 31061,

When compared to neighboring states, Georgia's record of Pleistocene vertebrate fossil localities is rather depauperate. However, excavations at Clark Quarry near Brunswick, Georgia, have yielded abundant in situ Pleistocene-aged vertebrate fossils in recent years. The locality is dominated by macrofossils of the large Columbian Mammoth (Mammuthus columbi) and Bison. A recently recovered Bison skull with attached horn cores allows for its specific identification (late Pleistocene Bison species can only be distinguished based on horn core dimensions). In addition to the skull, numerous cervical, thoracic, lumbar, and caudal vertebrae, numerous ribs, three scapulae, six humeri, two radio-ulnae, one femur, one tibia, and numerous podials of bison have been recovered. The skull exhibits a complete cranium, rostrum, a nearly complete left horn core and a partial right horn core. An estimate of the horn core spread (tip to tip) is 162 cm. The left horn core length on the upper curve (tip to burr) is approximately 77 cm. These measurements indicate that this species is the Giant Ice Age Bison (Bison latifrons). Radiocarbon (14C) dating with corrected Stable Isotope Ratio analysis on a partial radio-ulna of B. latifrons produced a date of 12,350 ± 70 YBP, which raises interesting questions about the evolution and reduction of horn core size in the Genus Bison. Bison latifrons had previously been thought to have been extinct since the late Wisconsinan, somewhere between 21,000 and 30,000 years ago. This date also raises interesting geologic questions. Previous geologic mapping in the area indicated that Clark Quarry lies within the Princess Anne Terrace of the Satilla Formation. However, the radiocarbon date suggests that the ages of the Princess Anne and Silver Bluff Terraces need to be reconsidered or that Clark Quarry sediments represent a more recent episode of fluvial cut and fill in these older sediments.