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

• Applicant: Professor Dr. Jochen B. W. Wolf
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology)
• Term: from 2005 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 20783324

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.

• DFG Programme: Research Grants