Experience-induced preference for short-sworded males in the green swordtail, Xiphophorus helleri

Most studies of female mating preferences have found preferences for males with greater trait expression. This has led to the suggestion that most female preferences are in the direction of greater sensory stimulation and may be the result of pre-existing sensory biases. Recently, studies have revealed that mating preferences can be lost or reversed, even in species where a pre-existing sensory bias appears to be the basis of female preferences. These studies concentrate on changes in female preferences on evolutionary timescales, and there is little evidence of whether female mating preferences based on pre-existing sensory biases can be altered by individual experience. Using green swordtail fish, we investigated whether female preferences for less ornamented males can be induced by manipulating early social experience. Throughout their early life females were exposed to either all long-sworded males, all short-sworded males or alternating long-and short-sworded males. Restricting experience in this way resulted in only females with experience restricted to short-sworded males developing any consistent preference, and this was for short-sworded males. This is the first evidence that female preferences based on pre-existing sensory biases can be altered ontogenetically and indicates such preferences can be remarkably labile. (c) 2008 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.