Australian Research Centre for Human Evolution, Griffith University, Brisbane, QLD 4111, Australia;
Archaeology and Natural History, College of Asia and the Pacific, The Australian National University, Canberra, ACT 2601, Australia.
Proc Natl Acad Sci U S A. 2021 May 18;118(20). doi: 10.1073/pnas.2023005118.
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 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.
现代人进入以前无人居住的岛屿生态系统与广泛的灭绝密切相关，而被引用为更新世巨型动物灭绝的一个关键原因是人类过度狩猎。根据全新世晚期的记录，一个常见的假设是人类总是对岛屿生物群产生负面影响，这需要将最近的人类行为和技术推断到考古学的过去。人类至少从更新世早期开始就在岛屿上，至少有 5 万年（ka）。在如此长的时间间隔内，发生重大的进化、行为和文化变化并不奇怪。然而，人类到达和岛屿灭绝之间的深层时间联系从未在全球范围内得到探索。在这里，我们检查了所有有记录的人类存在的更新世岛屿的考古学和古生物学记录，以研究人类是否一直是破坏性因素。我们表明，根据目前的数据，全球灭绝与更新世人类的到来之间无法联系，而且很难将其与环境变化的记录区分开来。直到全新世，技术、扩散、人口和人类行为的大规模变化才明显影响到岛屿生态系统。因此，我们目前正在经历的灭绝加速并不是内在的，而是最近文化复合体的一部分。
