20,000 Out of His League: The study of male guppy sexual selection based on female color and size

Abstract

Male guppies choose their mates based on various criteria. This study tests the effects of female body size and color on male sexual selection. Our hypothesis is that the larger, brighter females have a higher chance of reproductive success than the smaller, grey control fish, due to their genetic variations in size and color. This was tested by using one experimental fish and one control fish. In our study, the experimental fish was a large orange fish. The behaviors of the male were monitored and recorded over a period of five minutes. We found that the male guppy slightly favored the larger, orange guppy over the control guppy. These results support our hypothesis. We predict that these results occurred because larger females are easier to inseminate, and brighter colors catch the eye of the male.