Quantifying spatial patterns of kinship within and among groups of E. horsti

The spatial arrangement of kin underpins the potential for kin interactions, prevalence of inbreeding, and evolution of social behaviours. Kinship within marine populations has been historically understudied due to the prevailing assumption that long-distance larval dispersal would prevent close kin associations. We explored genetic relatedness within the sponge-dwelling reef fish Elacatinus horsti at three spatial scales in Curacao: within social groups on a sponge, within a reef site, and between reef sites. Our objective was to estimate genetic relatedness of individuals and determine if kinship varies across these three spatial scales.