Ancient genomes in South Patagonia reveal population movements associated with technological shifts and geography

Abstract

Archaeological research documents major technological shifts among people who have lived in the southern tip of South America (South Patagonia) during the last thirteen millennia, including the development of marine-based economies and changes in tools and raw materials. It has been proposed that movements of people spreading culture and technology propelled some of these shifts, but these hypotheses have not been tested with ancient DNA. Here we report genome-wide data from 20 ancient individuals, and co-analyze it with previously reported data. We reveal that immigration does not explain the appearance of marine adaptations in South Patagonia. We describe partial genetic continuity since ~6600 BP and two later gene flows correlated with technological changes: one between 4700–2000 BP that affected primarily marine-based groups, and a later one impacting all <2000 BP groups. From ~2200–1200 BP, mixture among neighbors resulted in a cline correlated to geographic ordering along the coast.

Ancient mitochondrial genomes from the Argentinian Pampas inform the early peopling of the Southern Cone of South America

“…The region is geographically the most distant from Beringia, the entry point of the first settlers of the Americas, and the archaeological record shows that humans arrived in the SCSA roughly 14.3 thousand years ago (kya) ( Dillehay et al., 2008 ; Politis and Prates, 2018 ), shortly after the initial colonization of the continent (∼16 kya, based on ancient DNA ( Llamas et al., 2016 )), indicating a rapid spread southwards ( Bodner et al., 2012 ; Prates et al., 2020 ). A growing body of genetic research addressing the population history of the SCSA has focused mostly on the southernmost archaeological and extant groups from Patagonia and Tierra del Fuego ( Lalueza et al., 1997 ; García-Bour et al., 2004 ; de Saint Pierre et al., 2012b ; de la Fuente et al., 2015 , 2018 ; Crespo et al., 2017 , 2018 ; Nakatsuka et al., 2020b ). However, despite its potential importance for the peopling of this region, only a few recent studies included populations from the eastern sector of the SCSA, the Argentinian Pampas ( Figure 1 ) ( Perez et al., 2009 ; Llamas et al., 2016 ; Posth et al., 2018 ; Postillone et al., 2020b ).…”

Bone density and genomic analysis unfold cold adaptation mechanisms of ancient inhabitants of Tierra del Fuego

“…This fact suggests that the skeletons in the roman collection might belong to Fuegians who lived at a time when contacts with European and North American sealers became relatively more systematic although a steady systematic contact with Europeans would have taken place from 1843 onwards when the Chilean government sent an expedition whose aim was to establish a new city that would serve as a centre for the economic development of the region. Thus, we do not know whether, according with previous observations 12 – 14 , the remains of the roman collection belong to individuals modern enough to show a mixture of European ancestry (reflecting post-colonial admixture).…”

“…These ethnic groups were identified as different communities in the XX century 11 . The descendants of Fuegians show a population continuity as supported by the genetic affinity of modern Yamana and Alakaluf with ancient individuals from their respective regions and a mixture of European ancestry reflecting post-colonial admixture 12 – 14 . What is known of the ancient inhabitants of Tierra del Fuego mostly comes from navigators and ethnographers’ reports 15 , 16 .…”

Desafíos éticos asociados al estudio y tratamiento de restos humanos en las ciencias antropológicas en el siglo XXI

“…Esto puede referirse tanto a ampliar el conocimiento respecto de movimientos de poblaciones antiguas (ej. Nakatsuka et al, 2020), como a la identificación individual de los restos esqueléticos alojados en museos (ej. Dahinten et al, 2020) o a futuras investigaciones sobre restos individuales que serán repatriados y sepultados (para los que se solicita el consentimiento siempre que sea posible) (ej.…”