Hips Don’t Lie: The Allure of Female Caudal Peduncle Depth for Male Guppy Mate Selection

Abstract

The interaction between the sexes of species is what has evolved their current populations. In this study, we conducted experiments on male guppies, Poecilia reticulata, in order to determine whether a female’s caudal peduncle depth influences a male’s sexual attraction to them. We used 3-D models of a control, smaller, and larger sized caudal peduncle depth in order to observe the males’ interaction with the female models. In our observations, we found that the male was in the zone with the female with the larger caudal peduncle depth for the longest duration when tested against the control, and it demonstrated the most courtship displays for this model than any other. This indicates that male guppies have a possible preference for females with larger caudal peduncle depths, which could initiate further studies in order to better support our theory and lead to better understanding of the breeding processes of other fish species as well.