Evolutionary Ecology of Mycophagous Drosophila

果蝇在遗传学、发育和进化的研究中发挥了核心作用。Jaenike博士的研究重点是果蝇的食用菌物种，这些物种非常适合研究这些昆虫的生态和行为。这项拟议研究的主要关注点将是这些果蝇与寄生它们的一种线虫之间的生态互动。由于这些果蝇中任何时候都有多达50%的果蝇被寄生，而且受感染的果蝇在生育能力方面严重衰弱，这些线虫对果蝇的种群有实质性的影响。一系列的野外和实验室研究将被用来调查线虫如何影响它们的果蝇宿主的生存、交配成功和竞争相互作用。生态因素，如环境温度、蘑菇种类和果蝇种群密度，如何影响寄生虫的频率也将被研究。这项研究将为宿主-寄生虫相互作用的生态学提供基本信息。此外，由于线虫有可能成为生物控制昆虫的重要媒介，这项工作可能会揭示如何最好地实施这种控制计划。Jaenike博士还计划研究他发现的影响一种果蝇性别比例的染色体。由于“性别比例”男性只生育女儿，这些染色体理论上预计会增加频率，最终导致种群灭绝。在现实中，他们不会这样做。Jaenike博士将研究可能阻止这些染色体传播的生态因素，包括竞争能力和对线虫寄生的敏感性。这项研究将提供关于一个水平(个体内的染色体)的选择如何被另一个水平(群体内的个体)选择所抵消的洞察力。

Drosophila have played a central role in the study of genetics, development, and evolution. Dr. Jaenike's research focuses on mushroom feeding species of Drosophila which are ideally suited to studies of the ecology and behavior of these insects. A primary concern of the proposed research will be with ecological interactions between these Drosophila and a species of nematode that parasitizes them. Because as many as 50% of these flies are parasitized at any time and because infected flies are seriously debilitated in terms of fertility, these nematodes have a substantial impact on populations of Drosophila. A series of field and laboratory studies will be used to investigate how nematodes affect survival, mating success, and competitive interactions of their Drosophila hosts. How ecological factors, such as ambient temperature, mushroom species, and Drosophila population densities, affect frequencies of parasites will also be examined. This research will provide basic information on the ecology of host-parasite interactions. In additions, because nematodes have the potential to be important agents for biological control of insects, this work could shed light on how best to carry out such control programs. Dr. Jaenike also has plans to study chromosomes which he has discovered to affect sex ratio in a species of Drosophila. Because "sex ratio" males sire only daughters, these chromosomes are expected in theory to increase in frequency and eventually cause population extinction. In reality, they do not do so. Dr. Jaenike will study ecological factors, including competitive ability and susceptibility to nematode parasitism, that may prevent the spread of these chromosomes. This research will provide insight on how selection at one level (chromosomes within individuals) is counteracted by selection at another level (individuals within populations).