Does Female Poecilia reticulata Size Play a Role in the Male Decision Process of Who to Mate With?

Abstract

Guppies choose a mate based on physical attributes. They will often display a courtship behavior, alerting to the other guppy that it would like to mate. They do this to avoid mating with the wrong species and to subdue the aggression of the female guppy so that mating can take place. We chose to conduct this experiment because we thought that the courtship behaviors displayed by the male guppy were very unique. Additionally, we wanted to test if a certain phenotype, female guppy size, had an effect on how much time the male spent with each female. We hypothesize that a male guppy placed in a tank with a larger and smaller female guppy will spend more time with the larger female guppy. Our data was collected from an online database where we were able to see how long the male guppy spent displaying courtship behavior depending on the size of the female’s body size. We tested a small (101003) versus a large size model (101002). We analyzed the data with a Mann-Whitney U test and by finding the average time the male guppy spent with each female model. We found that, on average, the male guppy spent about the same amount of time with the smaller and larger female guppy, with no significant difference. This meant that our hypothesis was not supported.