* Structure: The tapetum lucidum is a layer of tissue located behind the retina in the back of the eye. It's made of reflective crystals, often guanine, which act like tiny mirrors.
* Light reflection: When light enters the eye, some of it is absorbed by the retina, where it's converted into signals the brain can understand. But the tapetum lucidum reflects the remaining light back through the retina.
* Amplifying light: This reflection essentially "bounces" the light back through the retina, increasing the amount of light that reaches the light-sensitive cells. This allows cats to see better in low light conditions.
Think of it like this: Imagine shining a flashlight into a dark room. Some of the light will be absorbed by the walls, but some will bounce back, making the room appear brighter. The tapetum lucidum acts similarly, amplifying the available light to help cats see better in the dark.
Why do cats need this ability?
* Nocturnal lifestyle: Cats are crepuscular animals, meaning they are most active at dawn and dusk. This means they often hunt in low-light conditions.
* Predatory instinct: Cats are predators, and having good night vision helps them locate prey more easily.
Other animals with tapetum lucidum:
Many animals, including dogs, horses, cows, and even some fish and amphibians, have a tapetum lucidum. However, the structure and reflectivity vary between species.