Data from: Multi-generation genetic contributions of immigrants reveal cryptic elevated and sex-biased effective gene flow within a natural meta-population

Impacts of immigration on micro-evolution and population dynamics
fundamentally depend on net rates and forms of resulting gene flow into
recipient populations. Yet, the degrees to which observed rates and sex
ratios of physical immigration translate into multi-generational genetic
legacies have not been explicitly quantified in natural meta-populations,
precluding inference on how movements translate into effective gene flow
and eco-evolutionary outcomes. Our analyses of three decades of complete
song sparrow (Melospiza melodia) pedigree data show that
multi-generational genetic contributions from regular natural immigrants
substantially exceeded those from contemporary natives, consistent with
heterosis-enhanced introgression. Further, while contributions from female
immigrants exceeded those from female natives by up to three-fold, male
immigrants’ lineages typically went locally extinct soon after arriving.
Both the overall magnitude, and the degree of female bias, of effective
gene flow therefore greatly exceeded those which would be inferred from
observed physical arrivals, reshaping the eco-evolutionary implications of
immigration.