The Arrival of Homo sapiens into the Southern Cone at 14,000 Years Ago.

Gustavo G Politis,María A Gutiérrez,Daniel J Rafuse,Adriana Blasi,Michael D Petraglia

doi:10.1371/journal.pone.0162870

Abstract

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America.

Highlights

The current data from southern South America suggests Homo sapiens expanded into the Americas during a period earlier than the Clovis hunters of North America [1]
The radiocarbon dates from extinct fauna in the lower part of the stratigraphic units Y and S demonstrate an important chronological dispersion; the delimited horizontal and vertical spatial association in specific sectors of the site supports a close relation between Pleistocene fauna and lithic artifacts
While each one of the four lines of evidence resumed and discussed previously could be explained in some way without a human intervention; the combination of the four lines of evidence suggests that the hypothesis more parsimony (Occam's razor) is that which situates the human action as a central causal factor, not exclusive, in the formation of the extinct fauna bone assemblage and in its association with lithic artifacts

Summary

Introduction

The current data from southern South America suggests Homo sapiens expanded into the Americas during a period earlier than the Clovis hunters of North America (older than ca. 11,500 14C yrs B.P.) [1]. New data from the Pampas region of Argentina, support the association of extinct Pleistocene fauna and cultural remains at the Arroyo Seco 2 site (AS2), dated to 12,170 14C yrs B.P. The AS2 site is located just outside the city of Tres Arroyos, in the Pampa region of Argentina. It is an open-air archaeological site situated on a low lying knoll between a small temporary lake and a shallow creek (38°21'38" S, 60°14'39" W) (Fig 1 and S1 File). From 1979 to the most recent excavations in 2015, a total of 77 units (~314 m2) were opened in the AS2 site, including shovel tests and 3 long trenches (S1 Fig)

Objectives

Findings

Discussion

Conclusion