Micro- and macrogeographic genetic differentiation in a highly mobile species, the Galápagos sea lion (Zalophus californianus wollebaek)

传统上，种群间的遗传分化与地理障碍造成的分离模式密切相关。因此，遗传分化似乎更可能发生在传播能力有限的种群中。然而，越来越多的证据表明，高度流动的物种表现出意想不到的遗传结构，从微小的差异一直到物种形成，甚至在繁殖种群相互联系良好的环境中也是如此。因此，除了地理隔离或历史事件分离种群之外，必须援引其他机制来理解基因流动的潜在模式。在群居动物中，行为过程似乎在小范围和大范围的地理尺度上对遗传特性产生重大影响，并且可能与基因流动和空间分离在创造局部适应方面一样相关。我计划用加拉帕戈斯海狮，一种种群繁殖哺乳动物，来仔细研究行为对基因流动的重要性，既包括繁殖种群的局部规模，也包括整个加拉帕戈斯群岛的更大规模的种群。我将把正在进行的关于物种社会结构的研究数据与利用来自核和线粒体基因组的遗传标记的遗传分化模式联系起来。我的目的是揭示，系统的社会结构是否受到诸如地点保真度、分类交配、对群体内特定社会社区的依恋以及母系家庭范围遗传等行为的影响，并反映在基因分化模式中。

Traditionally, genetic differentiation among populations has been intimately associated with separation patterns imposed by geographical barriers. Genetic differentiation, therefore, seemed more likely to occur in populations with limited dispersal ability. There is, however, growing evidence that highly mobile species exhibit unexpected genetic structures ranging from small differences all the way to speciation even in environments, where breeding populations are well interconnected. Thus, mechanisms other than geographic isolation or historical events separating populations must be invoked to understand the underlying patterns of gene flow. In social animals behavioural processes seem to produce significant effects on genetic properties on small and larger geographic scales and could be as relevant to gene flow as spatial separation in creating local adaptation. I plan to use the Galapagos sea lion, a colonial breeding mammal, to scrutinize the importance of behaviour on gene flow on both the local scale within a breeding colony as well as on a larger scale among colonies throughout the entire Galapagos archipelago. I will relate data of an ongoing study on the species social structure to patterns of genetic differentiation using genetic markers from the nuclear and mitochondrial genome. My aim is to disclose, whether the system s social structure as influenced by behaviours such as site fidelity, assortative mating, attachment to a specific social community within a colony, and matrilineai home range inheritance, is mirrored by genetic divergence patterns.