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

0076212欧文国际研究员奖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。 该计划的奖项提供了机会，联合研究，并使用独特的或互补的设施，专业知识和实验条件国外。欧文在瑞典隆德大学的支持下与斯塔凡·本施博士合作了24个月。一个物种分裂成两个物种，或称物种形成，需要很长时间才能发生，因此很难直接观察。 环物种提供了一个研究物种形成的难得机会，在环物种中，一个长链或杂交种群包围着一个地理屏障;链中的终端种群不会在它们聚集在一起的地方杂交。 对于两个环物种--环绕波罗的海的杨柳莺和环绕中亚的绿柳莺--首席研究员将利用环周围的地理变异来重建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）在瑞典中部两种杨柳莺的接触区，两种莺的歌声是否存在差异，这些差异是否用于择偶？2)在绿柳莺环周围，迁徙模式是如何变化的？3)波罗的海周围的杨柳莺种群是否逐渐变化，从而连接瑞典南部和北方的形式？ 4)瑞典中部的混血儿的迁徙行为是什么？ 答案将阐明行为特征和选择对物种形成的杂交种的作用。本施博士使用新的技术来研究迁移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秀设施。***

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. ***