The Effects of Female Caudal Fin Depth Size on the Mate Choice of Male Guppies (Poecilia reticulata)

Abstract

The discovery of different factors that affect mating choices of organisms could lead to the next step of evolutionary biology. Guppies are a widely used organism in studying mating selection because they have such distinct mating behaviors. In this study, we tested the effects of female caudal fin depth on the mating choices made by male guppies. The average time and number of mating behaviors made by males towards two orange female guppy models was calculated. One model had a standard caudal fin depth and the other had a 5.1 mm increase in caudal fin depth. We hypothesized that male guppies would be more attracted to female guppies with a larger caudal fin depth because the larger female would appear to the males as being able to produce more offspring.