Speciation processes in two co-distributed freshwater turtle complexes in a hotspot of genetic diversity (Emys orbicularis complex; Mauremys caspica, M. rivulata)

将在海龟中研究异域物种形成的过程，海龟是一组能够广泛杂交的动物，即使在远亲类群中也是如此。为了更深入地了解尽管有这种杂交能力，但物种形成是如何发生的，我们计划使用多态性微卫星和mtDNA序列变异来分析两个具有不同程度生殖隔离、相似分布范围和相似生态特征的物种复合体中的基因流，以解决以下问题：（1）两个共分布的物种复合体是否表现出相同的分化、渐渗和基因流动的一般模式？(2)距离隔离和地理障碍对遗传不连续性的形成有什么影响？(3)与其他类群相比，它们的遗传分化和渐渗模式如何？龟类有没有什么特殊之处，可以帮助我们理解它们杂交的极端能力？(4)线粒体和核基因组模式在两个模型系统中是一致还是冲突？(5)尽管有共同的栖息地和相同或至少非常相似的选择力，它们的地理分布模式是一致的还是冲突的？

Processes underlying allopatric speciation will be studied in turtles, a group of animals capable of extensive hybridisation, even among distantly related taxa. To gain deeper insights in the question how speciation occurs despite this capability to hybridize, we plan to analyze gene flow in two species complexes with a different degree of reproductive isolation, with similar distribution ranges and similar ecological traits using polymorphic microsatellites and mtDNA sequence variation to address the following questions: (1) Do the two co-distributed species complexes show the same general patterns of differentiation, introgression, and gene flow? (2) What is the impact of isolation-by-distance and geographic barriers for the formation of genetic discontinuities? (3) How do the genetic differentiation and introgression patterns compare with other taxa? Are there any peculiarities in chelonians that might help to understand their extreme capability to hybridize? (4) Do mitochondrial and nuclear genomic patterns agree or conflict in each of the two model systems? (5) Are their phylogeographic patterns congruent or conflicting, despite shared habitats and identical or at least very similar selective forces?