Systematics, diversity & speciation of Lepidoptera

云杉芽蛾是北美针叶林的主要食叶害虫，尽管几十年来一直在努力管理其种群数量，但其定期爆发影响了森林结构，并造成了巨大的经济损失。旧大陆燕尾蝶类也受到了很多关注，尽管主要是因为它们很大，对博物学家有视觉吸引力。这两类鳞翅目昆虫都有一个共同的事实，即尽管经过多年的研究，我们仍然不知道它们包含多少种，以及如何区分它们。这可能是因为这些物种在某些地区正在分化，但在其他地区正在合并。我们想知道为什么会发生这种情况，因为这将使我们深入了解物种形成是如何发生的。换句话说，一个物种如何以及为什么会变成两个物种？新的物种有时会从以前不同的物种之间的杂交中形成吗？我的研究生将追踪云杉芽蛾及其亲属在属Choristoneura的起源和进化的背景下，他们与他们的树木，他们用于交配的引诱剂，以及大陆的传播路线，他们已经用来传播整个北方半球和非洲。他们还将研究当地景观结构在多大程度上影响整个北美燕尾蝶物种之间的交配和基因流动。在许多标本中有效测量大量基因的新技术使这成为进行此类研究的令人兴奋的时刻。我们终于可以问什么样的基因，以及有多少基因与种群的分化或合并有关。较早的研究表明，与物种差异相关的基因不成比例地存在于性染色体上，就蝴蝶和飞蛾而言，性染色体仅占其总基因组的3%左右。如果这是真的，那么如果我们想有效地诊断和了解飞蛾、蝴蝶和我们周围生命的多样性，也许我们应该首先研究这些染色体上的基因。

Spruce budworm moths are major defoliators of conifer forests in North America, influencing forest structure by their regular outbreaks and causing much economic damage despite many decades of effort to manage their population numbers. Butterflies of the Old World Swallowtail species group have received much attention as well, although mainly because they are large and visually attractive to naturalists. Both groups of Lepidoptera share the fact that we still don't know how many species they contain and how to tell them apart, in spite of years of study. This may be because these species are in the process of diverging in some areas but merging in others. We would like to know why this might be happening, since this would give us insight into how speciation occurs. In other words how and why can one species can turn into two species? And can new species sometimes form from hybridization between previously distinct species? My graduate students will trace the origin and evolution of spruce budworm moths and their relatives in the genus Choristoneura in the context of their associations with the trees they feed on, the attractants they use for mating, and the continental dispersal routes that they have used to spread across the Northern Hemisphere and through Africa. They will also study the extent to which local landscape structure influences mating and gene flow between the species of swallowtail butterflies across North America. New technologies for efficiently surveying large numbers of genes in many specimens have made this an exciting time to carry out this kind of study. We can finally ask what kinds of genes, and how many, are implicated in divergences or merging of populations. Older work has suggested that the genes associated with species differences are disproportionately found on the sex chromosomes which, in the case of butterflies and moths, make up only about 3% of their total genome. If that is true, then perhaps we should be looking first at the genes on these chromosomes if we want to effectively diagnose and understand the diversity of moths, butterflies, and life around us.