Dissertation Research: The Evolution and Development of Abdominal Pigmentation Patterns in Natural Populations of Drosophila polymorpha

果蝇属昆虫的腹壁色素沉着模式差异很大，尤其是南美洲的多态果蝇，表现出一系列腹部色素模式，有浅色、中色和深色三种。这些变形的频率随着时间和空间的变化而变化，表明这一特征是自然选择的结果，因此在物种的生态中很重要。这项拟议的研究旨在从发育和群体遗传学的角度来理解这种色素模式多态：1)检查导致物种内色素差异的发育过程；2)将色素差异与候选基因区域的变异联系起来；3)通过确定遗传变异在巴西自然群体中的空间分布来检查影响当前地理分布的微观进化力量。只有少数类似的研究在这样的微观进化水平上研究了形态进化的一般问题，并且这些研究中只有一部分研究了决定可变性状命运的进化力量。最后，这项建议的独特之处在于，它是一种多学科方法，将美国和巴西的发展生物学和群体遗传学的研究人员和方法结合在一起。

0104977TempletonAbdominal pigmentation pattern varies widely in the genus Drosophila.In particular, the South American species D. polymorpha exhibits a rangeof abdominal pigmentation patterns, with light, intermediate, and darkmorphs. The frequency of these morphs varies with time and space,indicating that this trait is under natural selection and thus importantin the ecology of the species. The proposed research aims to understandthis pigmentation pattern polymorphism from both developmental andpopulation genetic perspectives by: 1) examining the developmentalprocesses leading to pigmentation differences within the species; 2)correlating pigmentation differences with variation at candidate geneloci; and 3) examining the microevolutionary forces affecting currentgeographic distributions of the trait by determining the spatialdistribution of genetic variation in natural Brazilian populations.Only a few similar studies have investigated the general question ofmorphological evolution at such a microevolutionary level, and only asubset of these have addressed the evolutionary forces shaping the fateof a variable trait. Finally, this proposal is unique in that it is amultidisciplinary approach, uniting investigators and integratingmethods from both developmental biology and population genetics in both the United States and Brazil.