No Apparent Indirect Genetic Benefits to Female Red Flour Beetles Preferring Males with Intense Copulatory Courtship

Abstract

Whether females gain indirect genetic benefits through mate choice is a controversial issue since this requires additive genetic variance in the preferred male traits. Condition dependence could maintain the necessary genetic variance by linking the expression of male traits to the supposedly large number of genes affecting condition. Copulating males of the red flour beetle Tribolium castaneum rub their legs along the female elytra. Females favor males with vigorous rubbing through cryptic female choice. We measured the repeatability and heritability of this behavior and assessed its potential use as indicator of viability and condition. We found genetic variance in larval to adult survival and in the rate of leg rubbing in males. However, the rate of leg rubbing was not related to offspring survival or condition dependent. The genetic variance in leg rubbing was mostly non-additive with very low narrow sense heritability. Therefore, we failed to document any indirect genetic benefits to choosy females through viability of their offspring or attractiveness of their sons.