Collaborative Research: Host-Associated Genetic Differentiation in the Goldenrod Elliptical-Gall Moth Gnorimoschema Gallaesolidaginis - Parallel Host Race Formation?

草食性昆虫(1-500万种)的惊人多样性尚不为人所知，但它们多样化的一个可能机制是通过宿主种族形成的共地物种形成-即在没有地理障碍的情况下适应不同宿主植物并在不同宿主植物上形成物种。虽然在共生关系中有少数寄主小种的形成是已知的，但这一过程是罕见和特殊的，还是频繁和可预测的，仍然是未知的。攻击一枝黄花和一枝黄花的不同种类的昆虫为回答这个问题提供了一个很有希望的途径。针对这些昆虫中的一种--黄粉蛾，我们将使用遗传数据来记录遗传分化的地理范围和结构，重建寄主转移的历史，并确定驱动分化的进化力量。同时，我们将利用实验室和田间实验来确定维持寄主植物亲缘关系和生殖隔离的生态机制(例如，配偶选择、成虫和幼虫选择，和/或幼虫性能与寄主相关的权衡)。我们对一枝黄花分化的研究将补充正在进行的其他一枝黄花草食动物分化的研究。总而言之，这些研究将告诉我们许多关于寄主种族形成如何(以及多久)可能对食草性昆虫的壮观多样性做出贡献的信息。

0107752HeardThe astounding diversity of herbivorous insects (1-5 million species) is poorly understood, but one possible mechanism for their diversification is sympatric speciation via host race formation - that is, adaptation to and speciation on different host plants in the absence of geographic barriers to gene exchange. While a few cases of host race formation in sympatry are known, it remains un-known whether this process is rare and special or frequent and predictable. A promising avenue toward answering this question is provided by the diverse group of insects attacking the goldenrods Solidago altissima and S. gigantea. Focussing on one of these insects, the goldenrod elliptical-gall moth, Gnorimoschema gallaesolidaginis, we will use genetic data to document the geographic extent and structure of genetic differentiation, reconstruct the history of host shifting, and identify evolutionary forces driving differentiation. At the same time, we will use lab and field experiments to identify ecological mechanisms maintaining host plant affiliation and reproductive isolation (e.g. mate choice, adult and larval host choice, and/or host-associated tradeoffs in larval performance). Our studies of differentiation in G. gallaesolidaginis will complement ongoing studies of differentiation in other Solidago herbivores. Together, these studies will tell us much about how (and how often) host race formation might have contributed to the spectacular diversification of herbivorous insects.