Categorical perception occurs when continuous variation in a stimulus (e.g. wavelength of color) is categorized by observers with sharp changes in response occurring over a boundary and increased discrimination between stimuli that lie across a boundary as compared to within a category. We found that female zebra finches show categorical perception of colors in the red to orange visual spectrum that match colors used by males in sexual signaling. The results of this analysis are important to models of sexual selection and assessment signaling.
