Bi-parentally Inherited Genetic Evidence for Male-Biased Dispersal in Common Moorhen (Gallinula chloropus).

Dispersal is a life history trait that has relevant effect on both the dynamics and the genetics of species and sex-biased dispersal depends on how resource competition affects each of the sexes. In this study, a total of 210 blood samples including 121 Common Moorhen (Gallinula chloropus) females and 89 males were collected from 18 diverse areas during the breeding season. Based on 8 microsatellite markers analyses, we found that the most genetic diversities from female populations were higher than those from the males, where only 2 male individuals were identified as the long-distance dispersal. Analyses of sex-biased dispersal conducted over all sampling sites indicated that mAI (female mAI  = 0.195, male mAI  = - 0.265, P = 0.01), FST (female FST  = 0.045, male FST  = 0.026, P = 0.020), and r (female r = 0.118, male r = 0.064, P = 0.010) in females were all significantly higher than those in males at the 0.05 level, which suggested a male-biased dispersal pattern in this species. Our Mantel test results suggested a significant isolation-by-distance pattern for females but not for males, which corresponded to the more frequent dispersal and gene flow in males than in females. This dispersal pattern could be explained by the special life history trait and mating system that Common Moorhen pair formation occurs before they leave the flock in the spring to establish territories and its females initiate courtship more frequently than males and compete with each other to pair with small males with large fat reserves. The philopatric female could benefit most from knowledge of a particular area because they may win more intrasexual competitions in the breeding season and be able to produce more offspring if they are familiar with the local resources.