A second way to infer different levels of dispersal between the sexes is to compare male--male and female--female relatedness within populations, because the sex that does not disperse should show higher levels of relatedness than the sex that does disperse. The simplest way to test for this is to compare the relatedness between all male--male pairs and all female--female pairs within each population to see if overall values are higher in one sex than the other. Estimates of relatedness were used to compare female and male dispersal in the Australian lizard Egernia stokesii. The breeding partners of this genetically monogamous species live within aggregates that include offspring and other relatives. Although both sexes show some degree of philopatry, females within groups had higher overall levels of relatedness to one another (r = 0.1380) compared with the relatedness between males (r = 0.0433), and this was taken as evidence for male-biased dispersal (Gardner et al., 2001).
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