PRF/J: Molecular Evolution in Strepsirhine Primates

PRF/J：链霉素灵长类动物的分子进化

• 批准号: 9303313
• 负责人: Anne Yoder
• 金额: --
• 依托单位: Individual Award
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-06-01 至 1996-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9303313&HistoricalAwards=false
• 关键词: PRF; Molecular; Evolution; Strepsirhine; Primates

The intent here is to generate and compare mitochondrial and nuclear DNA sequences in order to explore the tempo and mode of sequence evolution in strepsirhine primates (e.g., lemurs and lorises). The primary objective of this research is to test two discrete hypotheses: (a) do lemurs show a reduced rate of molecular evolution compared to lorises and other primates?, and (b) do lemurs exhibit a slower transition rate? If it can be demonstrated that lemurs have experienced a molecular slowdown relative to other primates, this would indicate that generation time isn't the principal variable responsible for controlling the rate of primate evolution. A reduced overall rate of molecular evolution coincident with a depressed transition rate would be suggestive of a mechanism whereby overall rates can be retarded or accelerated. The large number of mtDNA and nuclear DNA sequences to be generated for a uniform taxonomic sample will enable comparisons of rates of evolution and phylogenies for the two data sets. A prime research strength of this approach is that molecular evolutionary phenomena are to be explored within a robust phylogenetic context. %%% Results are expected to shed light on our understanding of strepsirhine evolution and more specifically Malagasy lemuriforms, which exemplify biological diversity. In addition findings will impact the on-going debate over the reality of a molecular clock. The lack of consensus that predominates the current controversy is partly due to the poor phylogenetic grounding of many studies. A third justification for the study is its assessment of nuclear versus mitochondrial nucleotide sequences, an approach not taken so often. Estimation of the magnitude of mtDNA and nuclear rate differentials may affect the phylogenetic utility of those genes.

这里的目的是生成并比较线粒体和核 DNA 序列，以探索链霉素灵长类动物（例如狐猴和懒猴）的序列进化速度和模式。 这项研究的主要目的是测试两个独立的假设：（a）与懒猴和其他灵长类动物相比，狐猴的分子进化速度是否降低？（b）狐猴的过渡速度是否较慢？ 如果能够证明狐猴相对于其他灵长类动物经历了分子减速，这将表明世代时间并不是控制灵长类动物进化速度的主要变量。 分子进化总体速率的降低与转变速率的降低相一致，暗示着总体速率可以被延迟或加速的机制。 为统一的分类学样本生成大量线粒体 DNA 和核 DNA 序列，将能够比较两个数据集的进化速率和系统发育。 这种方法的主要研究优势是在强大的系统发育背景下探索分子进化现象。 %%% 结果预计将阐明我们对链球菌进化的理解，更具体地说是马达加斯加狐猴形，它体现了生物多样性。 此外，研究结果还将影响正在进行的关于分子钟真实性的争论。 当前争议主要是缺乏共识，部分原因是许多研究的系统发育基础较差。 这项研究的第三个理由是它对核核苷酸序列与线粒体核苷酸序列的评估，这种方法并不常见。 线粒体 DNA 和核率差异大小的估计可能会影响这些基因的系统发育效用。