Doctoral Dissertation Improvement: Nucleotide Substitution Rate Variation in the Catarrhini (Order Primates)

这项研究解决了分子进化研究中的一个公开问题：生物水平特征(如体重、饮食、行为)和分子特征(如DNA进化速度、基因组大小、物种内和物种间DNA变异)之间的联系。具体地说，世代时间、种群大小、代谢率、身体大小、自然选择的活动以及物种特定DNA复制准确性的差异如何影响DNA进化的速度？这个项目将通过检查一组经过充分研究的物种之间的DNA进化率差异来加深科学理解。研究重点将放在卡他灵长类动物上，这是一种包括人类、猿类和东半球猴子在内的哺乳动物群体，因为它们在生活史变量、生物学和生态学方面有着显著的和精心测量的差异。此外，有强有力的证据表明，这一群体内的DNA进化速度存在差异，因为有证据表明，人类和猿类的DNA进化速度比东半球的猴子慢。以前研究DNA进化速度变异的研究已经检查了广泛的DNA序列样本，但只在有限的几个远亲物种中--例如人、老鼠和牛。这项研究的不同之处在于，在相对亲缘关系较近的卡他灵长类动物的广泛样本中，抽样了一组10个独立的基因座。选择代表蛋白质编码和非编码(内含子、伪基因和基因间隔区)序列的基因座。最终，这个项目将有助于研究进化的方式、时间和原因，特别是与灵长类和人类进化有关的进化。这些结果可能会告诉我们：-现代东半球猴子物种是如何相关的？-现代类人猿的谱系是什么时候分化的？-孔雀猴子是如何以及何时在解剖学上变得专门吃树叶的？-人类的祖先是什么时候从最终导致黑猩猩的谱系中分化出来的？这是一个博士论文改进项目，是合作研究人员研究生培训不可或缺的一部分。研究成果将以学位论文和学术论文的形式发表，并在学术会议上发表。在研究过程中获得的DNA序列将保存在由国家生物技术信息中心(NCBI)托管的可公开访问的GenBank数据库中。

This research addresses an open issue in the study of molecular evolution: The connection between organismal level features (e.g. weight, diet, behavior) and molecular traits (e.g. rate of DNA evolution, genome size, DNA variation within and between species). Specifically, how do differences in generation time, population size, metabolic rate, body size, the activity of natural selection, and species-specific differences in DNA replication accuracy affect the rate of DNA evolution? This project will add to scientific understanding by examining DNA evolutionary rate differences within a well-studied group of species.The research will focus on the catarrhine primates, the mammalian group which includes humans, apes, and Old World monkeys, as they have significant and well-measured differences in life history variables, biology, and ecology. Furthermore, there is strong evidence for variation in the rate of DNA evolution within this group as there is evidence suggesting that humans and apes exhibit a slower rate of DNA evolution than the Old World monkeys. Previous studies investigating variation in the rate of DNA evolution have examined a broad sample of DNA sequences, but in a limited set of distantly related species - for example, human, mouse, and cow. This research differs by sampling a set of 10 independent loci in an extensive sample of relatively closely related catarrhine primates. The loci were chosen to represent protein coding and non-coding (introns, pseudogenes and intergenic) sequences. Ultimately, this project will contribute to the study of the how, when, and why of evolution, particularly as it pertains to primate and human evolution. The results may inform us as to: -How are the modern day Old World monkey species related? -When did the modern lineages of apes diverge? -How and when did the colobine monkeys become anatomically specialized for leaf eating? -When did the ancestors of humans become differentiated from the lineage ultimately leading to the chimpanzee?This is a doctoral dissertation improvement project integral to the co-investigator's graduate training. The research results will be published in a dissertation and scholarly papers, as well as presented at academic conferences. The DNA sequences obtained in the course of the study will be deposited in the publicly accessible GenBank database hosted by the National Center for Biotechnology Information (NCBI).