Research overview: short and long-wavelength cones in the cat retina

The two cone classes underlying feline color vision are usually described as a short-wavelength (blue-sensitive) cone and a longer-wavelength (green to yellow-sensitive) cone. This survey reviews microspectrophotometric and electrophysiological estimates of their peak sensitivities and their relatively low abundance in the cat retina. The presence of two spectrally distinct cones provides the substrate for the blue-yellow dimension of feline color discrimination, while the absence of a third, long-wavelength type explains the weak red-green discrimination reported behaviorally. The overview situates these cone types within the broader carnivore pattern of reduced color vision relative to primates. Because cones are outnumbered by rods, daytime color perception in cats is also coarse. Mapping the cone complement clarifies both what cats can see in color and why that capacity is modest compared with human vision.