Data from: Genetic covariance between components of male reproductive success: within-pair versus extra-pair paternity in song sparrows

We used comprehensive paternity data from socially monogamous but genetically polygynandrous song sparrows (Melospiza melodia) to estimate additive genetic variance and covariance in the total number of offspring a male sired per year outside his social pairings (i.e. his total extra-pair reproductive success achieved through multiple mating) and his liability to sire offspring produced by his socially paired female (i.e. his success in defending within-pair paternity).

Both components of male fitness showed nonzero additive genetic variance, and the estimated genetic covariance was positive, implying that males with high additive genetic value for extra-pair reproduction also have high additive genetic propensity to sire their socially paired female's offspring. There was consequently no evidence of a genetic or phenotypic trade-off between male within-pair paternity success and extra-pair reproductive success.

Such positive genetic covariance might be expected to facilitate ongoing evolution of polygyny and could also shape the ongoing evolution of polyandry through indirect selection. Usage notes male.cov.data.dryad.final Phenotypic data for the quantitative genetic analysis of male within-pair paternity success and extra-pair reproductive success. male.cov.Ainv.dryad.final Inverse A matrix underpinning quantitative genetic analysis of male within-pair paternity success and extra-pair reproductive success.