Guppy Mating Goggles: How well can a male guppy discern what species his mate is before interacting?

Abstract

We studied the mating behaviors of male guppy fish (Poecilia reticulata) in response to a female 3D model and a rectangle flag. The design of the experiment was to determine how well male guppies can discern one species from another. We tested this by placing a female model and a rectangle flag on opposite sides of an aquarium occupied by a male guppy. We then record the mating behaviors the male guppy directed towards each object. Our results showed the male guppies we used in the experiment to have a preference for the rectangular flag instead of the model guppy probably due to its larger size and better visibility in the water. A possible explanation for this that we offered is that guppies might not have the best eyesight and therefore gravitate toward the mates that are easier to see because they will also be the most viable mates to produce offspring that will reproduce.