Male offspring typically have greater variance in reproductive success than female offspring. Reproductive success of males in good condition should exceed that of females in good or poor condition, and female reproductive success should exceed that of males in poor condition. If condition and reproductive success are linked as proposed, then females in good condition should show a bias toward producing more male than female offspring. My research includes comparing clutches of females in good condition to those of females in poor condition to measure the effects of maternal condition on offspring sex ratios. I will also be determining if offspring sex ratio changes over the course of the breeding season.
House wrens can produce synchronous or asynchronously hatching broods.
I will also study the allocation of sexes with respect to hatching order in asynchronous broods.