REU: Furanocoumarins as Selective Agents on Parsnip WebwormPhysiology and Behavior

大多数植物和昆虫之间的化学共同进化理论都假定相互作用的物种影响着相互作用的遗传变化。然而，在自然系统中，很少有人研究确定的基因变化。在防风草虫和野生防风草虫之间的相互作用中，草食性随植物呋喃香豆素含量的不同而变化，网虫可以施加足够的选择压力来改变这些遗传控制的化学性状在植物种群中的分布。在这个项目中，将确定防风藤对呋喃香豆素的生理和行为反应在多大程度上受基因控制，以及这些化学物质是否能够施加足够的选择压力来改变网虫种群中生理和行为特征的分布。因此，这项研究不仅将为评估化学介导的共同进化的概念，而且也将为评估植食性昆虫的寄主适应和物种形成的更一般理论提供定量数据。

Most therories of chemical coevolution between plants and insects assume reciprocal genetic changes effected by the interacting species. Definitive genetic changes, however, have rarely been examined in natural systems. In the interaction between Depressaria pastinacella, the parsnip webworm, and Pastinaca sativa, the wild parsnip, herbivory varies according to plant furanocoumarin content and webworms can exert sufficient selection pressure to cause changes in the distribution of these genetically controlled chemical traits in plant populations. In this project, the extent to which physiological and behavioral responses to parsnip furanocoumarins are under genetic control in parsnip worms and whether these chemicals can exert sufficient selection pressure to change the distribution of physiological and behavioral traits in webworm populations will be determined. This study will therefore provide quantitative data for evaluating not only concepts of chemically mediated coevolution but also more general theories of host adaptation and speciation in herbivorous insects.