REU: Quantitative Genetic Analysis of Dimorphism in Diopsid Dipterans

这项研究的主要目的是了解导致性别形态和行为差异的进化机制。这在进化生物学中是一个特别活跃和有争议的领域。几种相互竞争的替代解释仍在考虑之中，部分原因是尚未获得适当的数据。虽然原则上可以使用在异性成员之间表现出差异的任何物种组，但这项研究集中在一组苍蝇上，这组苍蝇具有三个重要属性，使它们成为研究的理想对象。在一些物种中，雄性的眼睛长在茎的末端，其长度可以超过雄性体长的两倍，而雌性的茎要短得多。其他亲缘关系较近的物种表现出不那么戏剧性的二形性，少数物种根本没有二形性，眼柄非常短。这组人非常适合这项研究，因为1)这些巨大的差异仅限于一种特征。2)在同一地区有几个物种，可以在野外进行研究，最重要的是，这些物种中的大多数都可以在实验室饲养。后一个特征是至关重要的，因为繁殖实验可以确定这种特征背后的遗传基础，以及对女性择偶行为的遗传影响。这项研究的结果不仅应该让人们更好地了解这些苍蝇夸张的头部形状，而且还应该为洞察其他物种的性别二型性的机制和后果提供洞察。

The primary goal of this research is to understand the evolutionary mechanisms involved in causing morphological and behavioral differences in the sexes. This is a particularly active and controversial area in evolutionary biology. Several competing alternative explanations are still being considered, in part because appropriate data have not yet been obtained. While any group of species that showed differences between members of the opposite sexes could, in principle, be used, this research focusses on a group of flies which have three important attributes that make them ideal for this research. In some species, males have eyes on the ends of stalks which can attain lengths greater than two.times the male's body length while females have much shorter stalks. Other closely related species show less dramatic sexual dimorphism and a few species exhibit no dimorphism at all and have very short eye stalks. The group is uniquely suited to this research because 1) these dramatic differences are limited to a single trait. 2) several species occur in the same local area and can be studied in the field, and most importantly, 3) most of these species can be reared in the laboratory. This latter feature is critical because breeding experiments can identify the genetic basis underlying this trait as well as the genetic influence on female mate choice behavior. The results of this research should not only allow better understanding of the exaggerated head form of these flies, but should also provide insight into the mechanisms and consequences of sexual dimorphism in other species.//