Q: I recently adopted a handsome orange male tabby cat named Henry. At night, his eyes are luminescent, reflecting a variety of bright colors. Is he unusual, or do all cats’ eyes shine in the dark? What causes this magic?
A: Henry’s magic glow arises from the “tapetum lucidum,” Latin for “bright tapestry.” It’s a thick layer of iridescent cells behind the cat’s retina. Like a mirror at the back of the eye, the tapetum lucidum reflects light back onto the retina, increasing the light that hits it.
The tapetum lucidum, a structure common to animals that hunt after dark, gives cats their superior night vision. Human eyes don’t have this layer….