RUI: Collaborative Research: Host Expansion and Speciation Phytophagous Insects: Behavioral, Ecological, and Genetic Factors

生态学家和进化生物学家提出了草食性昆虫的物种形成模型，这些模型对遗传、行为和与寄主植物的生态相互作用做出了关键假设。验证这些假设将有助于我们更好地理解植物与食草动物之间的相互作用。如果这些假设在最近分化或正在分化的种群中得到验证，这些测试可以帮助确定几种相互竞争的物种形成模型中哪一种是最可信的。关于这些假设的假设将在两种密切相关的寄主植物上的两个产胆食草动物种群中进行测试。这些种群是一种形态的物种，由于寄主对交配和产卵的偏好不同，部分生殖隔离。了解导致这些偏好的遗传和其他机制对于理解草食动物物种形成的过程至关重要。这些问题将通过一系列的田间、实验花园和温室实验来探讨。寄主相关种群之间杂交的结果将用于确定寄主和交配地点的偏好以及在不同寄主植物上生存的能力是如何遗传的。为了确定环境和经验如何影响产卵和交配地点的偏好，将进行额外的实验。还将进行研究，以确定自然选择如何在可能选择种群分化的寄主植物之间有所不同。最后，在一个寄主相关种群中是否存在遗传变异可以预先适应向新寄主植物转移的行为将被研究。综合起来，这些数据将为植物-食草动物相互作用的生态学、寄主扩展的进化、物种形成以及农业害虫的专门适应提供见解。

Ecologists and evolutionary biologists have proposed speciation models for herbivorous insects that make critical assumptions about genetic, behavior, and ecological interactions with host plants. Testing these assumptions will lead to an improved understanding of plant-herbivore interactions. If these assumptions are tested in populations that have recently diverged, or are in the process of diverging, these tests can help determine which of several competing models of speciation are most plausible. Hypotheses about these assumptions will be tested in two populations of a gall-making herbivore on two closely related host plants. These populations are of one morphological species and are partially reproductively isolated due to differences in host preference for mating and egg-laying. Knowledge of genetic and other mechanisms responsible for these preferences are crucial to understanding how herbivore speciation occurs. These questions will be explored with a series of field, experimental garden, and greenhouse experiments. Results from crosses between the host-associated populations will be used to determine how host-and mating-site preferences and the ability to survive on different host plants is inherited. Additional experiments will be conducted to determine how environment and experience influence oviposition-and mating-site preference. Studies will also be conducted to determine how natural selection differs between host plants that could select for divergence of populations. Finally, whether there is genetic variation within one host-associated population could preadapt the behavior for a shift to a new host plants will be investigated. Taken together, these data will provide insight into the ecology of plant- herbivore interactions, the evolution of host expansions, speciation, as well as the specialized adaptations of agricultural pests.