@article {1793,
	title = {Offensive and defensive sperm competition roles in the dung beetle Onthophagus taurus (Coleoptera: Scarabaeidea)},
	journal = {Behavioral Ecology and Sociobiology},
	volume = {60},
	year = {2006},
	pages = {131-136},
	abstract = {Sperm competition is predicted to generate op- posing selection pressures on males. On one hand, selec- tion should favour {\textquoteleft}defensive{\textquoteright} adaptations that protect a male{\textquoteright}s ejaculate from displacement, while, on the other hand, selection should favour {\textquoteleft}offensive{\textquoteright} adaptations that overcome paternity assurance mechanisms of rivals. Here, we use the sterile male technique to assess sperm pre- cedence when a male dung beetle Onthophagus taurus mates in both a defensive (first male) and an offensive (second male) role. Significant variation in a male{\textquoteright}s sperm precedence (both P1 and P2) was detected, and an individual{\textquoteright}s defensive (P1) and offensive (P2) abilities were positively correlated. Thus, it appears that sexual selection simultaneously selects for {\textquoteleft}defensive{\textquoteright} and {\textquoteleft}of- fensive{\textquoteright} adaptations in O. taurus. We discuss a variety of male traits in O. taurus that potentially contribute to a male{\textquoteright}s ability to be successful whenmatinginan{\textquoteleft}of-fensive{\textquoteright} and a {\textquoteleft}defensive{\textquoteright} role. },
	keywords = {Defensive role, male genitalia, Offensive role, Onthophagus taurus, Sperm competition},
	author = {House, Clarissa M. and Simmons, Leigh W.}
}
