Why Do a Cat’s Eyes Shine at Night?
A cat’s eyes shine because they reflect light. Cats have a special mirror-like material in the back of each of their eyes.
This shiny layer, called the “tapetum lucidum,” helps a cat to see at night by catching even the faintest gleam of light.
This helps cats see better in low light by working like a mirror on the retina to reflect the light back through the eyes, giving them a second chance to absorb the light.
The colors seem more visible at night because the pupils are dilated wider than during the day, allowing more of the tapetum lucidum to be visible.
It also reflects the light from a street lamp or the light from your flashlight and causes the cat’s eyes to glow brightly. Many animals have eyes that seem to glow at night.
Scientists call the glow eye shine. Most animals that have eye shine are active at night. Dogs, deer, and raccoons have eye shine. So do bullfrogs and alligators.