The Phylogeny and Evolution of Cetacea: Resolution of Rapid Radiations and a Molecular Blueprint for Modern Whales, Dolphins, and Porpoises

鲸目动物的系统发育和进化：快速辐射的解析和现代鲸鱼、海豚和鼠海豚的分子蓝图

• 批准号: 1457735
• 负责人: Mark Springer
• 金额: $ 61.48万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1457735&HistoricalAwards=false
• 关键词: Phylogeny; Evolution; Cetacea; Resolution; Rapid

The evolutionary origin of Cetacea (whales, dolphins, and porpoises) in the Eocene, 50 million years ago, ranks among the best-documented macroevolutionary transitions. To non-scientists, this move from a terrestrial habitat to a committed aquatic lifestyle might seem improbable, yet the wholesale changes in anatomy required for this transformation are recorded in the fossil record. With the advent of genomics, it is now possible to study this remarkable evolutionary change at the molecular level. In this project, researchers will document the genetic basis of traits that were altered in the evolutionary genesis of these secondarily aquatic mammals and trace the molecular changes that produced a modern whale. In this project, researchers will train a postdoctoral scholar, graduate students, and multiple undergraduate interns at UC Riverside, a minority serving institution. The ethnically diverse makeup of UC Riverside provides an opportunity to bring cutting edge research to students who are historically underrepresented in science. Results from the research also will be incorporated into coursework and provide content for museum displays focused on evolutionary principles. Grant participants, including students, will collaborate with staff at the San Diego Natural History Museum to relate exciting research breakthroughs in a revitalized 'Fossil Mysteries' exhibit with bilingual educational modules.For Cetacea, standard phylogenetic analyses of fossil and molecular data have been used to reconstruct major phenotypic transformations in the group, with fossils providing signposts that place key evolutionary innovations relative to Earth history. Yet, despite ongoing phylogenetic studies based on large datasets, a fully resolved reconstruction of cetacean evolution has been elusive. The researchers propose a three-pronged approach to an enhanced study of cetacean evolutionary history that will utilize 500 genes to: 1) compare alternate approaches to the reconstruction of species trees using a robust sample of genetic data, 2) resolve problematic systematic relationships within Delphinidae (oceanic dolphins), Phocoenidae (porpoises), and Balaenopteroidea (rorquals and gray whale), 3) synthesize a phylogenomic blueprint for modern cetaceans. Exon capture and next generation sequencing methods will be employed to rapidly characterize candidate loci that represent genes predicted to have undergone adaptive or degenerative change. The researchers will target genes that are critical for behavioral and anatomical features that are highly derived in the group, including loci implicated in vision, hearing, olfaction, deep diving, aging, tooth development, baleen formation, and brain size. The end result will be the first, detailed, genomic characterization of a major macroevolutionary transition that is also documented by extensive fossil evidence.

始世于5000万年前，鲸类（鲸鱼，海豚和海豚）的进化起源是最有记载的宏观进化过渡中的。对于非科学家来说，从地面栖息地到忠实的水生生活方式似乎不可能，但是在化石记录中记录了这种转化所需的解剖结构的批发变化。随着基因组学的出现，现在可以研究分子水平的这种显着进化变化。在该项目中，研究人员将记录这些特征的遗传基础，这些遗传基础在这些次要的水生哺乳动物的进化起源中发生了变化，并追踪产生现代鲸鱼的分子变化。在该项目中，研究人员将在少数派服务机构加州大学河滨大学培训博士后学者，研究生和多个本科实习生。 UC Riverside的种族多样化的构成提供了一个机会，将历史上人为科学人数不足的学生带来尖端研究。研究结果还将纳入课程中，并为专注于进化原理的博物馆展示提供内容。 Grant participants, including students, will collaborate with staff at the San Diego Natural History Museum to relate exciting research breakthroughs in a revitalized 'Fossil Mysteries' exhibit with bilingual educational modules.For Cetacea, standard phylogenetic analyses of fossil and molecular data have been used to reconstruct major phenotypic transformations in the group, with fossils providing signposts that place key evolutionary innovations relative to Earth 历史。 然而，尽管基于大型数据集的系统发育研究进行了持续的系统发育，但鲸类进化的完全解决的重建仍然难以捉摸。研究人员提出了一种三管齐下的方法，以增强对鲸类进化史的研究，该方法将利用500个基因来：1）使用强大的遗传数据样本将替代方​​法比较替代方法与物种树木的重建，2）在Delphinidaee（大洋洲海豚），Poroteae（Poroter）（Poroter）和Balaen（poroite）中解决有问题的系统关系（2）鲸鱼），3）合成现代鲸类的系统基因组蓝图。 外显子捕获和下一代测序方法将用于快速表征候选基因座，该基因座代表预测的基因经历了自适应或退化性变化。研究人员将针对高度衍生在小组中的行为和解剖特征至关重要的基因，包括与视觉，听力，嗅觉，深度潜水，衰老，牙齿发育，Baleen形成和脑大小有关的基因座。 最终结果将是主要的宏观进化过渡的第一个，详细的基因组表征，这也通过广泛的化石证据进行了记录。