PATERNAL INVESTMENT IN RELATION TO SIZE IN THE DEATHWATCH BEETLE, XESTOBIUM-RUFOVILLOSUM (COLEOPTERA, ANOBIIDAE), AND EVIDENCE FOR FEMALE SELECTION FOR LARGE MATES

Male X. rufovillosum donate on average 13.5% of their body weight to t he female during copulation. The weight transferred is significantly g reater in heavier males and declines in subsequent matings. When virgi n females are offered a choice of several mates, they tend to mate wit h a heavy male. Females appear to be selective during courtship, refus ing to mate with light males. Artificial weights attached to males inc rease the frequency of acceptance as mates by females, but not signifi cantly. The evolutionary origins and significance of a large paternal investment and apparent female selection for heavy mates are discussed .