Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species.

摘要: Understanding how dispersal and gene flow link geographically separated the populations over evolutionary history is challenging, particularly in migratory marine species. In southern right whales (SRWs, Eubalaena australis), patterns of genetic diversity are likely influenced by glacial climate cycle recent whaling. Here we use a dataset mitochondrial DNA (mtDNA) sequences (n = 1327) nuclear markers (17 microsatellite loci, n = 222) from major wintering grounds to investigate circumpolar population structure, historical demography effective size. Analyses variation identify two clusters that correspond South Atlantic Indo-Pacific ocean basins have similar breeder estimates. contrast, all show significant differentiation for mtDNA, but no sex-biased was detected using genotypes. An approximate Bayesian computation (ABC) approach with compared scenarios through time, or isolation secondary contact between basins, while modelling declines abundance linked Secondary-contact yield highest posterior probabilities, implying different were largely isolated came into within last 25,000 years, role whaling changes generations could not be resolved. We hypothesise these findings driven factors promote isolation, such as female philopatry, dispersal, oceanographic changes. These highlight application ABC approaches infer connectivity mobile species complex histories and, currently, low levels differentiation.