Heterospecific courtship and sequential mate choice in sister species of field crickets

During mate selection, females of most species encounter males sequentially and may use a variety of decision rules whereby the attractiveness of a current potential mate is affected by sampling of previous individuals. The perceived distribution of male quality might therefore affect female mate choice. Mate choice among closely related taxa may additionally be affected by a perceived rarity of conspecifics. Here we tested whether female mate choice in the field crickets Gryllus rubens and G. texensis is affected by prior experience with either conspecific or heterospecific males. Specifically, we tested whether female acceptance of conspecific or heterospecific males is influenced by prior exposure to a conspecific or heterospecific male. Our results indicate that there is a clear previous-male effect, but that it differs across species. When ‘high-quality’ (i.e. conspecific) males are common, females are predicted to prefer them. Gryllus texensis females matched this prediction by showing clear preferences for conspecific males after prior experience with them, but G. rubens females showed the opposite effect: they preferred heterospecific males after prior experience with conspecific males. When prior experience is manipulated such that ‘low-quality’ (i.e. heterospecific) males are encountered first, female choosiness should be relaxed. Females of both species fit this prediction and showed no preference for conspecific or heterospecific males after prior experience with a heterospecific male.