To Mate, or Not to Mate: Attraction of Male Guppies to Females with Gravid Spot

Abstract

Guppies—Poecilia reticulata—are fishes of extreme interest in the eyes of researchers because of their small size and easily identifiable behaviors. Many factors influence male guppies’ choice in female sexual selection, including size, color, shape, and behaviors. Gravid spots, another factor for courtship behaviors, appear on females when they are pregnant or recently produced offspring. We hypothesized that males would show less courtship behaviors towards females without a gravid spot than females with a gravid spot. To test this, we created to model guppies: a control without a gravid spot and an experimental model with a gravid spot. Male guppies were exposed to the model fish and we recorded the amount of time that they spent on each side of the tank along with tallying the courtship behaviors that the guppies displayed. Our results do not show a reliable trend to support or reject our hypothesis. The male guppies displayed fin fanning and sigmoid curves towards both models, but did not display any gonopodal swings or biting.