REU: Molecular Phylogeny for Select Tetrapods

REU：特定四足动物的分子系统发育

• 批准号: 8918926
• 负责人: Linda Maxson
• 金额: $ 12万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-05-15 至 1993-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8918926&HistoricalAwards=false
• 关键词: REU; Molecular; Phylogeny; Select; Tetrapods

The classical phylogenetic tree depicting relationships among living tetrapods groups birds and crocodilians as each others closest genetic relatives. Recent molecular studies in our laboratory and some analyses of morphological and molecular data of others has suggested that birds may be more closely related to mammals than to crocodilians. The slow-evolving 18S and 28S nuclear ribosomal RNa (rRNA) genes are excellent probes for examining evolutionary relationships among living species, including the tetrapods. Collecting rRNA sequence data from additional species of amniotes will permit alternative hypotheses of relationships to be tested. The living amphibians are placed in three groups: frogs, salamanders, and caecilians. The caecilians are limbless animals which are found in tropical areas throughout the world. Nucleotide sequence data from the 28S nuclear rRNA gene and two mitochondrial genes (12S rRNA and cytochrome b) will be gathered from caecilians in order to examine evolutionary relationships within this group. Caecilians are ideal organisms for study biogeography and therefore knowledge of their relationships, needed for understanding past distributions, will be especially important.

描述关系的经典系统发育树 在现存的四足动物群中， 其他最接近的基因亲属。 最近的分子研究 我们的实验室和一些形态和分子分析 其他人的数据表明，鸟类可能更接近 与哺乳动物的亲缘关系远比鳄鱼更近。 进化缓慢的18S 28S核核糖体RNa（rRNA）基因是很好的探针 来研究现存物种之间的进化关系， 包括四足动物 收集rRNA序列数据， 其他种类的刺鼠将允许另一种假设 的关系进行测试。 现存的两栖动物被分为三类：青蛙， 蝾螈和螈。 无足目动物是没有四肢的动物 在世界各地的热带地区都有发现。 来自28S核rRNA基因的核苷酸序列数据和两个 收集线粒体基因（12 S rRNA和细胞色素B） 为了研究进化关系 在这个群体中。 无尾目是理想的研究生物 地理学以及对它们之间关系的了解， 了解过去的分布，将特别需要 重要.