Abstracts (first author)
The implications of reverse sex-biased dispersal for spatial genetic structure in a co-operatively breeding bird
Understanding the extent to which individuals differ systematically in dispersal propensity is crucial for quantifying patterns of gene flow in wild populations. For example, sex-biased dispersal can give rise to vastly different spatial patterns of relatedness between sexes, whereby the philopatric sex has a much higher density of relatives in the immediate neighbourhood. Such patterns can generate population genetic structure, whilst in co-operatively-breeding species such differences in local relatedness could potentially underpin observed asymmetries in levels of intergroup-conflict. We present long-term ecological data from a co-operatively breeding bird to show that whilst both sexes show restricted dispersal, males disperse significantly further than females from their natal groups. We quantify the capacity of this dispersal bias to drive sex-differences in fine-scale spatial genetic structure by using a pedigree of 600 individuals in concert with these ecological data to partition gene flow into that caused by both dispersal and extra-group matings, the latter having the potential to reinforce or disrupt emerging patterns of genetic structure. We discuss our results in the context of their implications for our understanding of the processes shaping patterns of inter-group conflict, and genetic differentiation over small spatial scales, in wild populations.