Hybridization of Darwin's Finches on the Galapagos Islands

小行星9306753 杂交的研究在进化生物学中很重要，因为它揭示了物种形成最后阶段的力量。 一些动物物种的种群通常会杂交，但要确定自然界中杂交的原因和后果通常是困难的。 拟议的研究利用了一个非常有利的情况下，调查杂交的原因和相对较高的适合度的杂交种的原因。 在加拉帕戈斯群岛的达夫尼梅杰小岛上，中型地雀偶尔会与其他两种鸟杂交; fuliginosa一个移民 系谱分析表明，杂交种可以在几年内生存和繁殖，甚至比亲本物种更好。 通过对摄食效率和饮食的深入研究，将调查其高适合度的生态原因。 通过分析东方棉和攀缘棉群体的近交效应，评估了杂合性增强可能带来的优势。 将通过交配模式的统计分析确定杂交的原因。%%% 有基本的和应用方面的拟议研究。 研究结果对我们理解物种形成具有重要的理论意义。 杂交在维持小的和潜在的濒危种群的遗传变异的作用的示范将是保护生物学的应用领域的价值。

9306753 Grant The study of hybridization is important in evolutionary biology because it reveals the forces at work in the final stages of speciation. Some populations of animal species commonly hybridize, but it is usually difficult if not impossible tho determine the causes and consequences of hybridization in nature. The proposed research takes advantage of an exceptionally favorable situation for investigating the causes of hybridization and the reasons for relatively high fitness of the hybrids. On the small island of Daphne Major in the Galapagos archipelago the medium ground finch, Geospiza fortis, occasionally interbreeds with the two others; G.scandens, a resident species, G. fuliginosa, an immigrant. Pedigree analysis has shown that hybrids may survive and breed as well or better than the parental species, over several years. Ecological reasons for their high fitness will be investigated by intensive study of feeding efficiencies and diets. Possible advantages arising from enhanced heterozygosity will be assessed by an analysis of inbreeding effects in the G.fortis and G.scandens populations. Causes of interbreeding will be identified by statistical analysis of mating patterns. %%% There are basic and applied aspects of the proposed research. Results will be of theoretical importance to our understanding of speciation. A demonstration of the role of hybridization in maintaining genetic variation in small and potentially endangered populations will be the value to the applied field of conservation biology.