Ecology of Darwin's Finches on the Galapagos Islands

9615383格兰特拟议研究的目标是了解物种形成和适应性辐射所涉及的过程。它将在加拉帕戈斯群岛的小岛达芙妮·梅杰进行。此前的研究表明，该岛上的三种达尔文雀偶尔会进行杂交。在过去的20年里，岛上几乎所有的个体都有独特的条带，系谱分析表明，在某些时候，杂交后代可能会存活下来，繁殖得与亲本物种一样好，甚至更好。拟议的研究将建立在长期数据集的基础上，以完成对1983年、1984年和1987年产生的所有物种和杂交品种的三个队列的人口统计学研究。这将是第一次对一群杂交种进行完整的分析，可能是针对自然界中的任何有机体。这项研究将涉及使用分子方法来明确分配亲子关系，以及使用生态学方法来确定个体命运差异的原因。完整的数据将允许测量杂交的长期遗传适合性结果，并将允许对这些相互作用的物种的长期动态进行建模。这项研究对于了解生物多样性的起源和维持具有重要意义。物种形成是产生生物多样性的关键过程，但人们对导致物种形成的生态和微进化力量知之甚少。这项拟议的研究利用了一个特别有利的情况，直接调查在物种形成的最后阶段发挥作用的一些力量，而杂交仍然是可能的。对于保护生物学来说，这项研究将有助于阐明影响小种群和潜在濒危种群遗传变异的生态因素。

9615383 Grant The goal of the proposed research is to understand the processes involved in speciation and adaptive radiation. It will be carried out on the small island of Daphne Major in the Galapagos archipelago. Previous research has shown that the three species of Darwin's Finches on the island occasionally hybridize. Over the past 20 years almost all individuals on the island have been uniquely banded, and pedigree analysis has shown that hybrids may survive and breed as well as or better than the parental species at certain times. The proposed research will build on the long-term data set to complete a demographic study of the three cohorts of all species and hybrids produced in 1983, 1984 and 1987. These will be the first complete analyses of a cohort of hybrids, possibly for any organism in nature. The study will involve using molecular methods to make unambiguous assignments of parentage, and ecological methods for determining the causes of variation in the fates of individuals. The complete data will allow a measurement of the long-term genetic fitness consequences of hybridization, and will allow modeling of the long-term dynamics of these interacting species. This research is important for understanding the origin and maintenance of biodiversity. Speciation is a key process for generating biological diversity, yet little is known about the ecological and microevolutionary forces responsible for speciation. The proposed research takes advantage of an exceptionally favorable situation for directly investigating some of the forces at work in the final stages of speciation when hybridization is still possible. For conservation biology, the research will help to illuminate the ecological factors that influence genetic variation in small and potentially endangered populations.