Effect of artificial selection on male colour patterns on mating preference of female guppies

Abstract

Theoretical models predict that the evolution of female mating preference may depend on a genetic correlation with the male traits on which preference depends. This correlation has been the subject of controversy, and has been demonstrated to exist in only a few cases. The relative extent of orange coloration exhibited by male guppies ( Poecilia reticulata ) contributes to the mating preference of female guppies in certain populations. If the predicted genetic correlation between preference and male traits exists, then artificial selection for increased and decreased amounts of orange in colour patterns of male guppies should result in corresponding shifts in female mating preference. Four separate selection experiments produced an immediate divergence in male colour patterns between high and low selection lines. Analysis of mate choice of females from the selection experiments provides some evidence for correlated divergence in preference as predicted by theory. Females from lines in which males were selected for increased orange tended to show stronger preference for orange than did females from lines selected for decreased orange. This kind of correlated change in preference could contribute to the correlated pattern of variation in colour pattern and female preference across guppy populations.