Raised Aggression in Male Guppies with Increased Competition

Abstract

Female-to-male interactions as well as male-to-male interactions both share equal importance in determining a male guppy’s (Poecilia reticulata) fitness. Yet, male-male guppy studies are greatly lacking among the scientific community. We designed an experiment that studies the male guppy’s response to the introduction of competition through a 3D model of a male with an enlarged gonopodium as well as a control of a 3D model of an average sized female. We hypothesized that the introduction of a male 3D model with an enlarged gonopodium will cause the live male guppy to show signs of aggression due to the threat of having competition and a threat to the guppy’s fitness.  Our results found that there was no statistical significance of guppies spending more time on the male side than the female side as well no significance in the shown signs of aggression toward the male model with the enlarged gonopodium.