International Research Fellow Award: The Role of Migration in Speciation: a Study of Two Ring Species

[00:76212 . 12] irwin国际研究员奖励计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。该计划的奖励为联合研究提供了机会，并利用独特或互补的设施、专业知识和国外的实验条件。该奖项将为达伦·e·欧文博士提供为期24个月的支持，让他与瑞典隆德大学的斯塔凡·本施博士一起工作。一个单一物种分裂为两个物种，或物种形成，需要很长时间才能发生，因此很难直接观察到。环状物种为研究物种形成提供了难得的机会，在环状物种中，长链或杂交种群围绕着地理屏障；链中的末端种群不会在它们聚集的地方杂交。对于两个环栖物种——环绕波罗的海的柳莺和环绕中亚的绿莺——首席研究员将利用环栖周围的地理变化来重建这两个物种是如何从一个物种进化而来的。他将与隆德的本施博士合作，重点研究四个问题：1)在瑞典中部两种柳莺的接触区，这两种柳莺的鸣叫是否存在差异，在择偶方面是否存在差异？2)绿林莺环的迁徙模式是如何变化的？3)波罗的海沿岸柳莺的种群是否有逐渐变化，从而将瑞典南部和北部的柳莺种群联系起来？4)杂交品种在瑞典中部的迁徙行为如何？答案将阐明行为特征和选择在物种中对抗杂交的作用。本施使用新技术来研究迁徙和测量种群之间的遗传差异。隆德大学拥有研究迁移和遗传变异的优良设施。＊＊＊

0076212IrwinThe International Research Fellow Awards Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will provide Dr. Darren E. Irwin with support for twenty-four months to work with Dr. Staffan Bensch at Lund University in Sweden.The splitting of a single species into two, or speciation, takes a long time to occur and is thus difficult to observe directly. A rare opportunity to study speciation is provided by a ring species, in which a long chain or interbreeding populations encircle a geographic barrier; the terminal populations in the chain do not interbreed where they come together. For two ring species - the Willow Warbler encircling the Baltic Sea and the Greenish Warbler encircling central Asia - the principal investigator will use geographical variation around the ring to reconstruct how two species evolved from one. He will work with Dr. Bensch at Lund to focus on four questions: 1) In the contact zone between two forms of the Willow Warbler in central Sweden, are there differences in songs between the forms and are the differences used in mate choice? 2) How do migration patterns vary around the Greenish Warbler ring? 3) Is there gradual variation in Willow Warbler populations around the Baltic, thereby connecting forms in southern and northern Sweden? 4) What is the migratory behavior of hybrids in central Sweden? The answers will clarify the role of behavioral traits and selection against hybrids in speciation.Dr. Bensch uses novel techniques to study migration and to measure genetic differences between populations. Lund University has excellent facilities for studying both migration and genetic variation. ***