Molecules, Morphology, and the Evolutionary Radiation of Placental Mammals

胎盘哺乳动物的分子、形态学和进化辐射

• 批准号: 9903810
• 负责人: Mark Springer
• 金额: $ 20万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9903810&HistoricalAwards=false
• 关键词: Molecules; Morphology; Evolutionary; Radiation; Placental; Molecules; Morphology; Evolutionary; Radiation; Placental

Springer9903810Living placental mammals comprise a group of approximately 4,000 species that are classified into 18 different orders (e.g., rodents, primates, rabbits and pikas, elephants, sea cows). Resolving evolutionary relationships among these orders has proved difficult. Fundamental questions concerning the evolutionary history of mammals remain unsettled. How did the breakup of ancient supercontinents affect the evolutionaryhistory of mammals? How did the extinction of dinosaurs and other large reptiles 65 million years ago influence the evolution of the major groups of mammals? How frequently have different kinds of adaptations (e.g., echolocation systems for navigation during flight) evolved among mammals? One approach to reconstruct evolutionary genealogy is to use DNA sequences. In our study, we will obtain DNA sequences for seven different genes from 97 placental mammals. The mammals that were chosen for this study are representative of all major groups. In addition to reconstructing anevolutionary genealogy, we will estimate divergence times among mammalianorders using a molecular clock. The evolutionary history that we reconstruct using molecules will provide a framework for evaluating how continental breakup and mass extinction have influenced mammalian evolution. We will also examine the origins of mammalian adaptations in light of the evolutionary tree that we obtain with DNA sequences.

Springer9903810胎盘哺乳动物包括一组约4,000种物种，分为18种不同的阶（例如啮齿动物，灵长类动物，兔子和长野，大象，海牛）。 事实证明，解决这些命令之间的进化关系很困难。 有关哺乳动物进化史的基本问题仍然不安。 古代超强的分裂如何影响哺乳动物的进化史？ 6500万年前，恐龙和其他大型爬行动物的灭绝如何影响主要的哺乳动物群体的演变？在哺乳动物中，多久具有多种不同种类的适应（例如，用于飞行过程中的回声定位系统）？ 重建进化谱系的一种方法是使用DNA序列。在我们的研究中，我们将获得来自97种胎盘哺乳动物的七个不同基因的DNA序列。为这项研究选择的哺乳动物代表了所有主要群体。除了重建进化的家谱外，我们还将使用分子时钟估计哺乳动物之间的差异时间。我们使用分子重建的进化史将提供一个框架，以评估大陆分裂和质量灭绝如何影响哺乳动物的进化。我们还将根据DNA序列获得的进化树来检查哺乳动物适应的起源。