The Influence of Late Quaternary Climate Change on the Ecology and Evolutionary Dynamics of Small Mammalian Herbivores

晚第四纪气候变化对小型食草哺乳动物生态及进化动态的影响

• 批准号: 0212370
• 负责人: Felisa Smith
• 金额: $ 7万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-15 至 2004-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0212370&HistoricalAwards=false
• 关键词: Influence; Late; Quaternary; Climate; Change

0212370SmithThis research investigates the evolutionary response of woodrats totemperature change over the late Quaternary. The project involves work at cave sites in the southwestern United States, using fossilized woodrat middens or debrispiles. Middens consist of plant fragments, fecal pellets and othermaterials embedded in crystalized urine ("amberat"); when sheltered incaves they persist for thousands of years. Measurements of radiocarbon-datedfecal pellets are used to estimate body size; for most mammals, size is sensitive toenvironmental temperature. Over the next year, we will investigate anumber of potentially problematic sampling and statistical dimensions ofour study system, including conducting studies with modern animals toexamine midden deposition and composition.Organisms may respond to anthropogenic climate change by adapting or goinglocally extinct. However, the timing, magnitude and nature of suchresponses remains unclear. The past ten thousand years are arguably thebest proxy we have for understanding the likely effects of anthropogenicclimate change. By examining different species of small rodents atdifferent locations within their range over the late Quaternary, andestimating the thermal thresholds at which different types of evolutionaryresponses occur, we may be able to better understand how future climatechange will impact mammalian populations.

0212370史密斯本研究探讨了晚第四纪林鼠对温度变化的演化响应。该项目涉及在美国西南部的洞穴遗址工作，使用化石化的woodrat middens或debrispiles。贝冢由植物碎片、粪便颗粒和其他嵌入结晶尿（“琥珀”）中的物质组成;当被遮蔽的贝冢时，它们会持续数千年。对放射性碳测年的粪便颗粒的测量可用于估计身体大小;对于大多数哺乳动物来说，身体大小对环境温度很敏感。 在接下来的一年里，我们将调查我们研究系统中一些可能存在问题的采样和统计维度，包括用现代动物进行研究，以检查垃圾的沉积和组成。生物体可能会通过适应或局部灭绝来应对人为气候变化。 然而，这种反应的时间、规模和性质仍不清楚。 过去的一万年可以说是我们理解气候变化可能影响的最好的代理。 通过研究第四纪晚期不同地区不同种类的小型啮齿动物，并估计不同类型的进化反应发生的温度阈值，我们可能能够更好地了解未来气候变化将如何影响哺乳动物种群。