2 research outputs found
Heterozygosity-based assortative mating in blue tits (Cyanistes caeruleus): implications for the evolution of mate choice
The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals
would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis)
and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses
in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a relatednessbased
mating pattern, but heterozygosity was positively correlated between social mates, suggesting that
blue tits may base their mating preferences on partner’s heterozygosity. We found evidence that the
observed heterozygosity-based assortative mating could be maintained by both direct and indirect
benefits. Heterozygosity reflected individual quality in both sexes: egg production and quality increased
with female heterozygosity while more heterozygous males showed higher feeding rates during the broodrearing
period. Further, estimated offspring heterozygosity correlated with both paternal and maternal
heterozygosity, suggesting that mating with heterozygous individuals can increase offspring genetic
quality. Finally, plumage crown coloration was associated with male heterozygosity, and this could explain
unanimous mate preferences for highly heterozygous and more ornamented individuals. Overall, this
study suggests that non-additive genetic traits may play an important role in the evolution of mating
preferences and offers empirical support to the resolution of the lek paradox from the perspective of
the heterozygous mate hypothesis.Peer reviewe