Are Cats Really Colorblind? Veterinarians Debunk Common Feline Sight Myths
By James H. Sterling
Human vision is generally trichromatic. The primate retina houses three distinct classes of photoreceptor cones tuned to blue (short-wavelength, ~420 nm), green (medium-wavelength, ~530 nm), and red (long-wavelength, ~560 nm). By combining signals across these three channels, the human brain constructs a spectrum containing roughly 1 million distinguishable shades.
The feline retina houses only two functional classes of cones. One responds to short-wavelength blue light around 450 nm, while the other responds to medium-wavelength green-yellow light near 555 nm. Feline sight operates as dichromatic vision, mirroring human protanopia or red-green color deficiency. Blue and violet shades appear clear and distinct. Greens, yellows, and teals register with clarity, though with lower saturation than what a human observer registers. Reds, oranges, magentas, and deep pinks lack dedicated photoreceptors; they register merely as darkened shades of gray or muddy brown.
James Sterling reports on renewable energy developments, climate policy, ecological conservation, and green tech innovations around the globe.
