Fitness consequences of differences in male mating behaviour in relation to female reproductive status in flour beetles

Abstract

In those species where females mate multiply, males that mate with non-virgin will generally share fertilizations with previous mates. As a result, males are expected to have evolved mechanisms to assess female reproductive status to maximize their fertilization success. This study examine dwhether male flour beetles, Tribolium castaneum, can distinguish between virgin and previously mated females by comparing mate behaviour of males given equal access to females differing in reproductive status. Males preferentially approached and contacted virgin females, and copulated significantly more often with virgin females compared to previously mated females. Female reproductive status did not appear to affect the probability of a copulation attempt once contact had been made with the female, or the probability that a copulation attempt woulf be successful. Males mating with virgin females gained a significant reproductive advantage compared to matings with previously mated females, siring more progeny with each mating. Possible factors that may influence selection for male ability to distinguish and preferentially mate with virgin females are discussed, including patterns of sperm precedence and female re-mating intervals.