|| 要旨トップ | 目次 |||日本生態学会第62回全国大会 (2015年3月、鹿児島) 講演要旨
一般講演（口頭発表） I1-21 (Oral presentation)
Postcopulatory sexual selection in internally fertilizing animals can select for harmful male genitalia, which injure mates during copulation and affect female fitness. Harmful male genitalia may further affect fitness of heterospecific females given interspecific copulation, particularly during secondary contact. Male Callosobruchus seed beetles have spines on their genitalia, and C. chinensis males reduce the fecundity of C. maculatus females via interspecific copulation, of which underlying mechanism is unknown. By exploiting phenotypic variation among nine separate C. chinensis strains, we found that (i) the more exaggerated the genital spines of C. chinensis males were, the more likely they were to induce genital injury in C. maculatus females, and that (ii) the genital injury translated into fecundity loss. That is, genital spines affected heterospecific fitness via interspecific copulation and genital injury. Harmful male traits due to sexual selection may generally affect the extent of interaction between closely related species.