title: Synergistic roles of climate warming and human occupation in Patagonian megafaunal extinctions during the Last Deglaciation.
abstract: The causes of Late Pleistocene megafaunal extinctions (60,000 to 11,650 years ago, hereafter 60 to 11.65 ka) remain contentious, with major phases coinciding with both human arrival and climate change around the world. The Americas provide a unique opportunity to disentangle these factors as human colonization took place over a narrow time frame (~15 to 14.6 ka) but during contrasting temperature trends across each continent. Unfortunately, limited data sets in South America have so far precluded detailed comparison. We analyze genetic and radiocarbon data from 89 and 71 Patagonian megafaunal bones, respectively, more than doubling the high-quality Pleistocene megafaunal radiocarbon data sets from the region. We identify a narrow megafaunal extinction phase 12,280 ± 110 years ago, some 1 to 3 thousand years after initial human presence in the area. Although humans arrived immediately prior to a cold phase, the Antarctic Cold Reversal stadial, megafaunal extinctions did not occur until the stadial finished and the subsequent warming phase commenced some 1 to 3 thousand years later. The increased resolution provided by the Patagonian material reveals that the sequence of climate and extinction events in North and South America were temporally inverted, but in both cases, megafaunal extinctions did not occur until human presence and climate warming coincided. Overall, metapopulation processes involving subpopulation connectivity on a continental scale appear to have been critical for megafaunal species survival of both climate change and human impacts.
authors.affiliation: Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.; Department of Ecology and Evolutionary Biology, Ramaley Biology, University of Colorado, Boulder, CO 80309-0334, USA.
authors.forename: Jessica L
authors.identifier: 0000-0001-8374-8046
authors.initials: JL
authors.lastname: Metcalf
authors.affiliation: Climate Change Research Centre, School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, Australia.
authors.forename: Chris
authors.initials: C
authors.lastname: Turney
authors.affiliation: Henry Wellcome Ancient Biomolecules Centre, Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.; Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen, Denmark.
authors.forename: Ross
authors.identifier: 0000-0003-4023-0284
authors.initials: R
authors.lastname: Barnett
authors.affiliation: Centro de Estudios del Hombre Austral, Instituto de la Patagonia, UMAG, Avenida Bulnes 01890, Punta Arenas, Chile.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Martin
authors.affiliation: Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.; Acute Leukaemia Laboratory, Centre for Cancer Biology, University of South Australia, Adelaide South Australia 5001, Australia.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Bray
authors.affiliation: Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen, Denmark.
authors.forename: Julia T
authors.identifier: 0000-0001-6534-8452
authors.initials: JT
authors.lastname: Vilstrup
authors.affiliation: Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen, Denmark.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Orlando
authors.affiliation: Institut des Sciences de l'Evolution, Université de Montpellier, CNRS, IRD, EPHE, Montpellier 34095, France.; Departamento de Paleontologia de Vertebrados, Museo de Historia Natural, UNMSM, Avenida Arenales 1256, Lima 14, Peru.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Salas-Gismondi
authors.affiliation: Instituto Nacional de Antropología y Pensamiento Latinoamericano, C1426BJN Ciudad de Buenos Aires, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Loponte
authors.affiliation: Área de Arqueología y Etnohistoria, Centro de Estudios Históricos "Prof. Carlos S.A. Segreti," Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Miguel C. del Corro 308, Córdoba (5000), Argentina.
authors.forename: Matías
authors.initials: M
authors.lastname: Medina
authors.affiliation: Instituto Nacional de Antropología y Pensamiento Latinoamericano (INAPL), CONICET/UBA, 3 de Febrero 1370, C1426BJN Buenos Aires, Argentina.
authors.forename: Mariana
authors.identifier: 0000-0002-8659-9725
authors.initials: M
authors.lastname: De Nigris
authors.affiliation: Instituto Nacional de Antropología y Pensamiento Latinoamericano (INAPL), CONICET/UBA, 3 de Febrero 1370, C1426BJN Buenos Aires, Argentina.
authors.forename: Teresa
authors.initials: T
authors.lastname: Civalero
authors.affiliation: Instituto Nacional de Antropología y Pensamiento Latinoamericano (INAPL), CONICET/UBA, 3 de Febrero 1370, C1426BJN Buenos Aires, Argentina.
authors.forename: Pablo Marcelo
authors.initials: PM
authors.lastname: Fernández
authors.affiliation: CONICET, Laboratorio de Paleoecología Humana, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Gasco
authors.affiliation: CONICET, Laboratorio de Paleoecología Humana, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina.
authors.forename: Victor
authors.initials: V
authors.lastname: Duran
authors.affiliation: Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Seymour
authors.affiliation: CONICET-IANGLA Grupo Vincualdo San Rafael/ UTN-MHNSR, Parque Mariano Moreno (5600), San Rafael, Mendoza, Argentina.
authors.forename: Clara
authors.initials: C
authors.lastname: Otaola
authors.affiliation: CONICET-IANGLA Grupo Vincualdo San Rafael/ UTN-MHNSR, Parque Mariano Moreno (5600), San Rafael, Mendoza, Argentina.
authors.forename: Adolfo
authors.initials: A
authors.lastname: Gil
authors.affiliation: Departamento Científico de Arqueología. Facultad de Ciencias Naturales y Museo, UNLP, Avenida Paseo del Bosque s/n (1900), La Plata, Buenos Aires, Argentina.
authors.forename: Rafael
authors.initials: R
authors.lastname: Paunero
authors.affiliation: Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n, (5301), Anillaco, La Rioja, Argentina.
authors.forename: Francisco J
authors.identifier: 0000-0003-0511-4720
authors.initials: FJ
authors.lastname: Prevosti
authors.affiliation: School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Corey J A
authors.initials: CJ
authors.lastname: Bradshaw
authors.affiliation: CONOPA, Instituto de Investigación y Desarrollo de Camélidos Sudamericanos, Lima, Peru.
authors.forename: Jane C
authors.identifier: 0000-0001-9020-0660
authors.initials: JC
authors.lastname: Wheeler
authors.affiliation: CONICET-IMHICIHU, Universidad de Buenos Aires. Saavedra 15, 5 (1083 ACA), Buenos Aires, Argentina.
authors.forename: Luis
authors.initials: L
authors.lastname: Borrero
authors.affiliation: Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
authors.forename: Jeremy J
authors.initials: JJ
authors.lastname: Austin
authors.affiliation: Australian Centre for Ancient DNA, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.; Henry Wellcome Ancient Biomolecules Centre, Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK.
authors.forename: Alan
authors.initials: A
authors.lastname: Cooper
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000737:chemistry / Q000378:metabolism; D000071194:Camelidae / Q000145:classification / Q000235:genetics; D057231:Climate Change; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D053476:Extinction, Biological; D045989:Felidae / Q000145:classification / Q000235:genetics; D006802:Human Activities; D006801:Humans; D046448:Ice Cover; D055110:Radiometric Dating; D017422:Sequence Analysis, DNA; D013020:South America; D001503:Ursidae / Q000145:classification / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial
keywords: Antarctic Cold Reversal; PATAGONIA; Pleistocene; South America; climate; extinction; human occupation; megafauna; mitochondrial DNA; radiocarbon