The peopling of the Americas and the interaction of early humans with Pleistocene megafauna in South America remains highly debated. Recent discoveries suggest that human occupation of the Americas started around the Last Glacial Maximum (LGM), but the timing and routes remain a highly debated and contentious topic.
In an article published today in the Proceedings of the Royal Society B led by Thais Pansani, a PhD student at Universidade Federal de São Carlos and Université Paris-Saclay, the multi-modal characterization of remains from the Santa Elina shelter (Central Brazil) provides new insights into this discussion. This site presents sequential human occupations dated from before the Last Glacial Maximum (~27,000 years ago) to early Holocene (~ 2,000 years ago). In the oldest archaeological layer (~27,000 years ago), stone tools are associated with megafaunal remains (giant sloth Glossotherium phoenesis), including three dermal bones (i.e., osteoderms) that are perforated, polished, and shaped anthropically. These bones were previously reported using digital photographs as possible ornaments made by early humans that have inhabited Santa Elina, but this claim lacked robust evidence of their ancient and anthropic modification.
Our international team performed multiple investigations on the three ornaments using a combination of advanced imaging methods, including UV/visible photoluminescence and synchrotron-based microtomography to assess whether these bones were intentionally modified by humans, and whether modification occurred on fresh bones, by contemporaneous humans, or on already fossilized bones by humans from recent settlements. I was particularly involved in the processing and interpretation of the microtomography data.
Our results show clear human-made marks on these bones and hole perforations, and our experimental approach corroborates that these modifications were made in fresh bones before the Late Glacial Maximum. In addition, we also present new 2D and 3D maps of the stone tool and megafaunal remains that show a clear temporal and spatial association of them in Santa Elina during two distinct phases dated to ~ 27,000 and ~13,000 years ago. This provides compelling evidence of human-megafauna interaction in Santa Elina, Central Brazil, before the Late Glacial Maximum.
Reference: Pansani T.R., Pobiner B., Gueriau P., Thoury M., Tafforeau P., Baranger E., Vialou A.V., Vialou D., McSparron C., de Castro M.C., Dantas M.A.T., Bertrand L. & Pacheco M.L.A.F. 2023. Evidence of artefacts made of giant sloth bones in central Brazil around the last glacial maximum. Proceedings of the Royal Society B 290, 20230316. Find the article (Open Access) here