Male Courtship Behavior in Guppies (Poecilia reticulata): Female Coloration, Gravid Spot, and Size

Abstract

Studies on mate selection in fish have offered insight into trait preferences and courtship behaviors that are relevant across species. Some of these include variation in size, body coloration, and gravid spot, or indicators of spawning or fertility, in female fish. In this study, behavior of male guppies was evaluated relative to female guppy characteristics, under the premise of previously studied mate choice in other fish species, with the goal of better identifying preferences among male guppies. The observation that male fish behavior varies relative to female fish characteristics led us to ask, what particular female characteristics elicit this change in male response? We hypothesized that variation in female coloration, size, and presence of a gravid spot would achieve different responses from male guppies, with the prediction that males would prefer females with greater coloration, larger size, and presence of gravid spot coloration. Various methodologies have been developed to study mating preferences in a lab setting, such as the use of 3D printed models. We presented male guppies with 3D printed models representing control and experimental conditions of female mates to observe choice of our subjects. Experimental models were subject to change in color, size, and presence of gravid spot. Our findings suggest that the factor of coloration is more important than size or gravid spot in mate choice of male guppies, where bright coloration is preferred to dark coloration.