Mate Choice and Copulation Frequency in the Burying BeetleNicrophorus quadripunctatus(Coleoptera: Silphidae): Effect of Male Body Size and Presence of a Rival

Seizi Suzuki

doi:10.1155/2009/904604

Abstract

It is widely assumed that there exists a competition between males for mating and that females prefer males with elaborate male traits. Further, such traits are considered to be synonymous with high quality in terms of benefits to females. The number and duration of copulations and the frequency of mate refusal between large and smallNicrophorus quadripunctatusmales were examined both for single males and for two males competing. The number of copulations was not affected by the size of the male or by the presence of a rival, but there was a significant interaction such that large males increased their number of copulations when a small rival was present. Copulation duration was not affected by male size but was shortened by a rival male. Females rejected copulation attempts of small males more often than of large males, whether the males were alone or paired with a rival. These results suggest that large males have two advantages: they win contests between males and are preferred by females.

Highlights

Species which provide biparental care often exhibit monogamous mating behaviors since assistance from the male is essential for successful breeding [1]
Significant interaction between male size and the presence of rivals suggests that large males repeatedly copulated in the presence of small males than that of a single large male (F = 8.29, P < .01, d.f. = 1, two-way ANOVA, Figure 1)
The dominant male achieves higher paternity, but inferior males often stay around the carcass and copulate in N. vespilloides [18, 19]

Summary

Introduction

Species which provide biparental care often exhibit monogamous mating behaviors since assistance from the male is essential for successful breeding [1]. Monogamous males fertilize most of the brood, but extrapair fertilizations (EPFs) have been observed in various species [2]. Since EPFs decrease the fitness of male partners, the frequency and/or influence of EPFs is reduced by male partners. Male partners react to EPFs by guarding their mates and frequent copulations [3]. Females prefer males with some specific traits because fertilization with high-quality males brings about direct and/or indirect benefits [4]. The success of EPFs depends on both the competition between males and the mate preferences by the female; the interaction between these factors is poorly understood

Methods

Results

Conclusion