Dissertation Research: Small Population Evolution and Slightly Deleterious Mutations: A Test of Nearly-Neutral Theory

论文研究：小群体进化和轻微有害突变：近中性理论的检验

• 批准号: 9972737
• 负责人: Andrew Martin
• 金额: $ 1万
• 依托单位: University of Colorado at Boulder
• 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: 1999-07-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9972737&HistoricalAwards=false
• 关键词: Dissertation; Research; Small; Population; Evolution

Martin9972737Populations of endangered species are of special concern because they typically persist as small populations. Small population size heightens the probability of extinction. In addition, theoretical studies indicate that small populations accumulate deleterious mutations because genetic drift overwhelms the purifying effects of selection, a phenomenon that further increases the likelihood of extinction. The investigators will conduct theoretical studies of genetic drift to determine the accumulation of deleterious mutations in populations. Populations of pupfishes in the deserts of western Nevada provide an excellent system to test whether extremely small populations accumulate significantly more mutations than larger populations. One of the populations, that of the Devil's Hole pupfish, has the unfortunate distinction of being the smallest vertebrate population. For a series of populations of different size, the rates and patterns of mutation accumulation will be assessed by comparative analysis of DNA sequences for several mitochondrial genes to test the predictions of the theoretical models.By documenting genetic effects of small population size, conservation biologists will gain insights into how small populations evolve. Information about the relationship between population size and mutation accumulation will advance understanding about the influence of evolutionary forces in extinction.

马丁9972737濒危物种的种群尤其值得关注，因为它们通常以小种群的形式存在。小的种群规模增加了灭绝的可能性。此外，理论研究表明，小种群积累有害突变是因为遗传漂变压倒了选择的净化作用，这种现象进一步增加了灭绝的可能性。研究人员将对遗传漂变进行理论研究，以确定种群中有害突变的积累。内华达州西部沙漠中的小鱼群提供了一个很好的系统，可以测试极小的种群是否比较大的种群积累了更多的突变。其中一个种群，魔鬼洞小鱼，不幸的是，它是最小的脊椎动物种群。对于一系列不同大小的种群，将通过对几个线粒体基因的DNA序列的比较分析来评估突变积累的速率和模式，以测试理论模型的预测。通过记录小种群规模的遗传影响，保护生物学家将深入了解小种群是如何进化的。关于种群大小和突变积累之间关系的信息将促进对灭绝中进化力量影响的理解。