No evidence for widespread island extinctions after Pleistocene hominin arrival

Abstract

The arrival of modern humans into previously unoccupied island ecosystems is closely linked to widespread extinction, and a key reason cited for Pleistocene megafauna extinction is anthropogenic overhunting. A common assumption based on late Holocene records is that humans always negatively impact insular biotas, which requires an extrapolation of recent human behavior and technology into the archaeological past. Hominins have been on islands since at least the early Pleistocene and Homo sapiens for at least 50 thousand y (ka). Over such lengthy intervals it is scarcely surprising that significant evolutionary, behavioral, and cultural changes occurred. However, the deep-time link between human arrival and island extinctions has never been explored globally. Here, we examine archaeological and paleontological records of all Pleistocene islands with a documented hominin presence to examine whether humans have always been destructive agents. We show that extinctions at a global level cannot be associated with Pleistocene hominin arrival based on current data and are difficult to disentangle from records of environmental change. It is not until the Holocene that large-scale changes in technology, dispersal, demography, and human behavior visibly affect island ecosystems. The extinction acceleration we are currently experiencing is thus not inherent but rather part of a more recent cultural complex.

Ancient proteins resolve controversy over the identity ofGenyorniseggshell

“…A scenario of human-megapode interaction therefore throws a completely different light on the debate over human role(s) in Australian megafauna extinctions, supporting environmental-driven hypotheses. This would be in line with recent studies, which have argued that there is no link between the arrival of humans and the extinction of megafaunas for the global Pleistocene record (21), and that Sahul extinctions were chronologically coupled with hydroclimate deterioration and not with anthropogenic effects (22).…”

Scientists’ warning – The outstanding biodiversity of islands is in peril

“…Hominins have been roaming on islands since at least the early Pleistocene, and Homo sapiens for at least 50 Ka. However, the impact of these early dwellers on the biota of the islands they inhabit, was moderate and, in any case, difficult to disentangle from environmental changes ( Louys et al, 2021 ). It was not until the beginning of the current interglacial that changes in subsistence strategies (hunter-gatherers to herders and farmers), political organization, technology, dispersal (i.e.…”

Cryptic extinction risk in a western Pacific lizard radiation

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