Ecological and Historical Determinants for Body Size Evolution: Insular/Mainland Contrasts in Three Reptile Systems in the Sea of Cortez

9318906案例这个项目测试了一个假设，即生态相互作用是墨西哥科尔特斯海三个独立的岛屿爬行动物系统：SauroMalus，Cnemidophorus和Crotalus身体大小急剧变化的原因。个体大小变化的历史是从种群之间的系统发育关系中推断出来的，正如通过核和线粒体DNA序列重建的那样。这些历史信息被用来检验种群对与竞争物种共生的遗传反应的假说。这项研究使用新技术来检验长期存在的关于字符移位的假设。这项研究很重要，因为它允许重新评估种群对竞争(性格置换)的遗传反应的一些经典例子，并对竞争与捕食在种群和群落结构的遗传变化中的作用产生新的见解。了解岛屿物种生态相互作用的影响可用于保护和管理小型孤立种群(例如，对引入的捕食者和竞争对手的敏感性)。这项研究也为健全实施濒危物种立法提供了科学背景。***

9318906 Case This project tests the hypothesis that ecological interactions are responsible for the dramatic body-size changes in three independent island reptile systems: Sauromalus, Cnemidophorus, and Crotalus in the Sea of Cortez, Mexico. The history of body size changes is inferred from the phylogenetic relationships among populations, as reconstructed from nuclear and mitochondrial DNA sequences. This historical information is used to test hypotheses of the population genetic response to sympatry with competing species. This research uses new technques to test long-standing hypotheses about character displacement. %%% This research is important because it allows re-evaluation of some of the classic examples of population genetic response to competition (character displacement) and yields new insights into the roles of competition vs. predation in the genetic change of populations and structure of communities. Understanding the effects of ecological interactions of island species can be applied to conservation and management of small isolated populations (e.g., sensitivity to introduced predators and competitors). This research also provides scientific background for sound implementation of endangered species legislation. ***