Sexual selection, antennae length and the mating advantage of large males in Asellus aquaticus.

摘要: In crustacean species with precopulatory mate-guarding, sexual size dimorphism has most often been regarded as the consequence of a large male advantage in contest competition for access to females. However, body males may also be favoured indirectly through scramble competition. This might partly case if actual target selection is morphological character, closely correlated size, involved detection receptive We studied on and antennae length natural populations Asellus aquaticus, an isopod mate guarding. this species, are larger than females pairing success positively related size. have longer antennae, relative females, suggesting that character by selection. used multivariate analysis assess influences five different field. Selection gradients indicated overall was better predictor length, although some variation observed between sites. then manipulated series experiments conducted laboratory, compared ability short or long antennae. Males were less likely detect, orient pair female discuss implications our results studies relation crustaceans.