Female pheromone and the behaviour of male guppies (<i>Poecilia reticulata</i>) in a temperature gradient

Abstract

When the two sexes of the guppy are tested separately in a horizontal temperature gradient apparatus, males show a significantly lower temperature preference (23.5 °C) than females (27.4 °C). However, when the two sexes are tested together, males select the same location as the females. Infusion of female holding water, which contains sex pheromone, results in the attraction of males to the site of infusion, as does the infusion of a water mixture of estradiol-17β, but not estrone, estriol, or testosterone. Temporarily plugging the nares, thereby blocking olfaction, prevents the males from responding to the chemical cues.