A Fossil Bone of a Giant Ground Sloth from the Last Millennium of the Pleistocene: New Data from Salto Department, Uruguay

Abstract

During the Pleistocene-Holocene transition at ~10.0 uncalibrated, or ~11.7 calibrated kya, the Americas were undoubtedly inhabited by humans from north to south ends. The groups living in that time had cultural and adaptive differences in terms of subsistence and technological pursuits. Particularly in the southern cone of South America, archaeological remains witnessed hunter-gatherers living at ~11.0-10.0 uncalibrated kya. They mostly used the so-called "fishtail," or just "Fell" points, a widespread Paleo-American marker. Despite that, they exploited different faunal species, including extant and extinct fauna. At the Salto Department in the northwestern region of Uruguay, on the Itaperibí Grande creek shore, archaeological remains of bones and stones were recovered. One of the most remarkable is a fragmented fossil femur of Lestodon armatus, a mega-mammal giant ground sloth. In its anterior face, this specimen shows diverse kinds of marks. However, no clear association among the findings was documented. Then, in order to check the possible relationship between the bone and the artifacts, the specimen was subjected to radiocarbon dating and it was analyzed in detail from a taphonomic perspective to evaluate the origin of the marks. The radiocarbon assay indicates that the specimen belongs to the last millennium of the Pleistocene. The date is relevant as it is one of the few assays obtained on a sample from that time. The taphonomic study revealed that the marks were not produced by human activity, hence, its primary relationship with the stone artifacts is uncertain. Despite that, these data make an important contribution to the knowledge about the fauna contemporaneously living with the earliest hunt-How to cite this paper: Nami, H. G.,

Fell points from Merín Lagoon, Uruguay: new data and their relevance to the peopling of south-eastern South America

“…The fossil findings indicate that these lands may not only have accommodated fauna: the presence of open plains, important fluvial courses, animals and other resources would have been sufficiently attractive to hunter-gatherers. Isotope values obtained from Late Pleistocene bones suggest a predominantly arid/semi-arid environment, with grasses, shrubs and tree vegetation (Czerwonogora et al 2011; Bocherens et al 2017; Loponte & Corriale 2019; Nami et al 2020). Furthermore, in southern Brazil and north-eastern Uruguay, the sea-level rise and retreat—mainly between 8/7 and 4.5 kya—formed the chain of lagoons.…”