Collaborative Research: Genetic Analysis of Regressive Evolution

洞穴动物之所以令人着迷， 它们生活的栖息地，以及它们 在黑暗中度过一生。 本研究的目的 是为了解开形态变化的原因， 伴随着洞穴中的生命，它作为一个模型系统， 理解结构的进化损失或减少， 就像人类的阑尾一样。 主要研究者将 调查洞穴中眼睛缩小的原因 一种小型虾状动物小钩虾的种群 眼睛 损失可能发生，因为动物的眼睛是在一些 在洞穴中处于不利地位，也许是因为浪费能源;或者 眼睛丧失可能仅仅是由于 减少眼睛的突变。 使用各种统计数据 技术，主要研究人员将确定是否 小眼睛的动物比大眼睛的动物有任何优势。 大眼睛的洞穴环境，以及动物是否与 大眼睛比小眼睛的动物有任何优势， 春天的环境 初步结果显示， 选择在眼睛的丧失中起着关键作用。 利用分子遗传学技术， 估计群体间的遗传差异，PI的 也将决定是否入侵和隔离在洞穴，其 可预测的形态学后果，已经很常见了。 领域 这个项目的工作将在一系列的洞穴中进行， 西弗吉尼亚州和弗吉尼亚州的温泉。

Cave animals hold a fascination both bacause of the strange habitat in which they live, and the modifications that they've undergone for life in darkness. The purpose of the present study is to unravel the cause of the morphological changes that accompany life in caves, which serves as a model system to understand the evolutionary loss or reduction of structures such as the appendix in humans. The principal investigators will investigate the cause of the reduction of eyes in cave populations of a small shrimp-like animal, Gammarus minus. Eye loss may happen either because animals with eyes are at some disadvantage in the cave, perhaps because of wasted energy; or eye loss may occur simply due to the random accumulation of mutations that reduce the eyes. Using a variety of statistical techniques, the principal investigators will determine whether animals with small eyes have any advantage over animals with large eyes in the cave environment, and whether animals with large eyes have any advantage over animals with small eyes in the spring environment. Preliminary results indicate that natural selection plays a critical role in the loss of eyes. Using techniques of molecular genetics that provide an estimate of the genetic differences among population, the PI's will also determine if invasion and isolation in caves, with its predictable morphological consequences, has been frequent. Field work for this project will be done in a series of caves and springs in West Virginia and Virginia.