Dissertation Research: The Role of Hybridization in the Evolution and Diversification of Heliconius Butterflies

进化研究的主要目标之一是解释新物种起源的机制。其中一个机制是由于先前建立的物种之间的杂交而形成新物种（或通过种间杂交形成物种）。为了了解杂交是如何产生新物种的，本项目将追溯最近通过杂交产生的热带蝴蝶物种Heliconius pachinus与其亲本物种之一H. cydno。据推测，自H. pachinus形式，自然选择导致了维持物种完整性的机制的进化。 该项目将通过检查这些机制并通过比较两个物种在整个范围内的遗传组成来确定这两个物种之间发生了多少遗传交换。虽然杂交在动物进化中的作用比以往任何时候都受到更多的关注，但动物中通过杂交形成物种的明确例子很少。一旦完成，这项研究将提供一个最完整的解释物种通过杂交。此外，这里提出的分歧机制是一个新的和令人兴奋的过程，物种形成可能已经发生了很多次，在这个属和其他。这种令人难以置信的相似性一直让生物学家感到惊讶，但仍然缺乏机械的解释。这里提出的假设很可能是对整个现象的解释。

One of the primary goals of evolutionary research is to explain the mechanisms by which new species originate. One such mechanism that has received relatively little attention is the formation of new species due to interbreeding between previously established species (or, speciation via interspecific hybridization). In an effort to understand how new species originate due to hybridization, this project will trace the history of divergence between Heliconius pachinus, a tropical butterfly species that recently originated via hybridization, and one of its parental species, H. cydno. It is hypothesized that since the origin of the H. pachinus form, natural selection has led to the evolution of mechanisms by which species integrity is maintained. This project will determine how much overall genetic exchange is occurring between these two species by examining these mechanisms and by comparing the genetic makeup of both species throughout their range.Although the role of hybridization in animal evolution is receiving more attention than ever, there are few clear examples of speciation via hybridization in animals. Once finished, this study will provide one of the most complete explanations of speciation via hybridization. Furthermore, the mechanism of divergence proposed here is a novel and exciting process by which speciation may have occurred many times in this genus and others. The incredible correspondence of mimetic Heliconius species pairs has long amazed biologists and still lacks a mechanistic explanation. The hypothesis put forward here could well be the explanation for this entire phenomenon.