The sensitivity of Neotoma to climate change and biodiversity loss over the late Quaternary

The late Quaternary was a time of considerable environmental change in North America. Not only was climate highly variable, but a megafaunal extinction at the terminal Pleistocene led to considerable loss of biodiversity. These combined perturbations likely had cascading effects across communities and ecosystems. Here, we focus on a detailed fossil record on the Edwards Plateau in Texas and the response of Neotoma, a genus of herbivorous rodents, to these environmental and ecological perturbations. We characterized changes in Neotoma body mass and diet across the past 20,000 years; body mass was estimated using measurements of fossil teeth and diet quantified using stable isotope analysis of carbon and nitrogen isotope from fossil bone collagen. We found that prior to ~7,000 cal yr BP, maximum mass was positively and significantly correlated to precipitation and negatively correlated to temperature. Independently, body mass was significantly and negatively correlated to communtiy compos...

晚第四纪（late Quaternary）是北美地区环境发生显著变化的时期。这一时期不仅气候波动剧烈，更新世末期发生的巨型动物群灭绝事件还造成了生物多样性的大幅丧失。这些复合扰动可能对群落与生态系统产生级联效应。本研究聚焦于德克萨斯州爱德华兹高原的精细化石记录，以及植食性啮齿动物林鼠属（Neotoma）对上述环境与生态扰动的响应。我们刻画了过去2万年以来林鼠属的体重与食性变化：体重通过化石牙齿的测量数据估算，食性则通过对化石骨胶原中的碳、氮同位素开展稳定同位素分析进行量化。研究发现，在约7000校准年代年前（cal yr BP）之前，林鼠属的最大体重与降水量呈显著正相关，与温度呈显著负相关。此外，体重还与群落组成……