3D-Printed Fish Models for Testing Guppy Mate Choice

A study of proximate causation of mate choice can help to engage students in the topic of sexual selection. We developed a new and flexible method for observing mate choice behavior in guppies (Poecilia reticulata.) Students observe male preference for 3D-printed fish models of female fish of different sizes, colors, and shapes to determine what traits are important in sexual selection. In their first week, the students expose a male guppy to a standard suite of different 3D-printed models. They then request modifications for the next week and the week afterward. The investigation engages students' abilities to carefully observe animals, quantify those observations, and use evolutionary reasoning to communicate their findings in a scientific manuscript peer-reviewed by anonymous new scientists. The use of 3D printers overcomes a hurdle (crafting accurate models that can be manipulated) making this type of authentic research accessible to a large and broader audience.