Inbreeding, Allee effects and stochasticity might be sufficient to account for Neanderthal extinction

Autoři: Krist Vaesen aff001;  Fulco Scherjon aff002;  Lia Hemerik aff003;  Alexander Verpoorte aff002
Působiště autorů: School of Innovation Sciences, Eindhoven University of Technology, Eindhoven, The Netherlands aff001;  Human Origins Group, Faculty of Archaeology, University of Leiden, Leiden, The Netherlands aff002;  Biometris, Mathematical and Statistical Methods, Wageningen University, Wageningen, The Netherlands aff003
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225117


The replacement of Neanderthals by Anatomically Modern Humans has typically been attributed to environmental pressure or a superiority of modern humans with respect to competition for resources. Here we present two independent models that suggest that no such heatedly debated factors might be needed to account for the demise of Neanderthals. Starting from the observation that Neanderthal populations already were small before the arrival of modern humans, the models implement three factors that conservation biology identifies as critical for a small population’s persistence, namely inbreeding, Allee effects and stochasticity. Our results indicate that the disappearance of Neanderthals might have resided in the smallness of their population(s) alone: even if they had been identical to modern humans in their cognitive, social and cultural traits, and even in the absence of inter-specific competition, Neanderthals faced a considerable risk of extinction. Furthermore, we suggest that if modern humans contributed to the demise of Neanderthals, that contribution might have had nothing to do with resource competition, but rather with how the incoming populations geographically restructured the resident populations, in a way that reinforced Allee effects, and the effects of inbreeding and stochasticity.

Klíčová slova:

Conservation biology – Extinction risk – Inbreeding – Neanderthals – Paleoanthropology – Paleogenetics – Population size – Species extinction


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2019 Číslo 11