Sex-specific genetic structure is a commonly observed pattern among vertebrate species. Facing differential selective pressures, individuals may adopt sex-specific life history traits that ultimately shape genetic variation among populations. Although differential dispersal dynamics are commonly detected in the literature, few studies have used genetic structure to investigate sex-specific functional connectivity. The recent use of graph theoretic approaches in landscape genetics has demonstrated network capacities to describe complex system behaviours where network topology represents genetic interaction among subunits. Here, we partition the overall genetic structure into sex-specific graphs, revealing different male and female dispersal dynamics of a fisher (Pekania [Martes] pennanti) metapopulation in southern Ontario. Our analyses based on network topologies supported the hypothesis of male-biased dispersal. Furthermore, we demonstrated that the effect of the landscape, identified at the population level, could be partitioned among sex-specific strata. We found that female connectivity was negatively correlated with snow depth, whereas connectivity among males was not. Our findings underscore the potential of conducting sex-specific analysis by identifying landscape elements or configuration that differentially promotes or impedes functional connectivity between sexes, revealing processes that may otherwise remain cryptic. We propose that the sex-specific graph approach would be applicable to other vagile species where differential sex-specific processes are expected to occur.
Usage Notes:
Microsatellite genotypes of fisher (Pekania [Martes] pennanti, Erxleben, 1777) of the Great Lakes region, Ontario, Canada
This fisher genetic database contains 722 individuals from 34 townships. Each individual is scored at 16 microsatellite loci. Township (or Site ID), sex, sample ID, coordinates and alleles in two column format are provided. See also: Carr D, Bowman J, Kyle CJ et al. (2007) Rapid homogenization of multiple sources: genetic structure of a recolonizing population of fishers. The Journal of Wildlife Management, 71, 1853–1861.
FisherGenotypes.csv