REVERSAL OF A FEMALE PREFERENCE AFTER VISUAL EXPOSURE TO A PREDATOR IN THE GUPPY, POECILIA-RETICULATA

To test the hypothesis that female choice has been subject to direct s election by predators, it was investigated whether female guppies woul d switch their choice of mate from more to less conspicuous males afte r observing a potential predator. Social and sexual preferences of vir gin females for each of two males differing in amount of carotenoid pi gmentation (an ornamental trait) were measured both before and after v isual exposure to a novel predatory cichlid. Females initially showed strong social and sexual preferences for the brighter of the two males . Preferred males also showed lower levels of fluctuating asymmetry in the area of carotenoid pigmentation and displayed at higher rates. Af ter exposure to the cichlid, almost half of the females became sexuall y unreceptive, and the remainder showed a nearly unanimous sexual pref erence for the duller male. Control females that did not see the cichl id continued to prefer the brighter male. These results imply that pre dators have selected against females that mate with conspicuous males. They also suggest that predators can influence sexual selection on ma le ornaments proximately through their effects on female choice as wel l as by imposing mortality on conspicuous males. Both conclusions sugg est that indirect selection on female preferences may not play a domin ant role in this system. (C) 1996 The Association for the Study of Ani mal Behaviour