Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Bentley, WA, 6102, Australia.
Division of Ecology and Evolution, Research School of Biology, ANU College of Science The Australian National University, Canberra, ACT, 2600, Australia.
Nat Commun. 2020 Jun 2;11(1):2770. doi: 10.1038/s41467-020-16502-3.
Large-scale changes in global climate at the end of the Pleistocene significantly impacted ecosystems across North America. However, the pace and scale of biotic turnover in response to both the Younger Dryas cold period and subsequent Holocene rapid warming have been challenging to assess because of the scarcity of well dated fossil and pollen records that covers this period. Here we present an ancient DNA record from Hall's Cave, Texas, that documents 100 vertebrate and 45 plant taxa from bulk fossils and sediment. We show that local plant and animal diversity dropped markedly during Younger Dryas cooling, but while plant diversity recovered in the early Holocene, animal diversity did not. Instead, five extant and nine extinct large bodied animals disappeared from the region at the end of the Pleistocene. Our findings suggest that climate change affected the local ecosystem in Texas over the Pleistocene-Holocene boundary, but climate change on its own may not explain the disappearance of the megafauna at the end of the Pleistocene.
更新世末期全球气候的大规模变化显著影响了北美洲的生态系统。然而,由于缺乏涵盖这一时期的、年代准确的化石和花粉记录,评估生物群更替的速度和规模一直具有挑战性,这种更替既包括新仙女木冷期,也包括随后的全新世快速变暖。在这里,我们展示了来自德克萨斯州霍尔洞穴的古 DNA 记录,该记录记录了来自大块化石和沉积物的 100 种脊椎动物和 45 种植物类群。我们表明,当地的植物和动物多样性在新仙女木冷却期间明显下降,但尽管植物多样性在全新世早期恢复,动物多样性却没有。相反,五种现存和九种已灭绝的大型动物在更新世末期从该地区消失。我们的研究结果表明,气候变化影响了德克萨斯州的当地生态系统在更新世-全新世边界,但气候变化本身可能无法解释更新世末期巨型动物的消失。