Can Cats See In The Dark?

Cats cannot see in complete darkness, but they can see better in the dark than we can. They can also see better in the dark than most other animals. The way a cat’s eye is structured is the reason for this. Cat’s have extremely large eyes for the size of their head. However these large eyes serve an important purpose and are quite unique compared to other animals. The cat’s eyeball is formed by several layers of tissue. The white part is known as the ‘sclera’. The sclera is made up of tough fibrous tissue rich in blood vessels. These blood vessels transport oxygen and nutrients to the contents of the eye. The clear outer part that covers the eye is known as the cornea. Made up of extremely thin layers of cells, the cornea is arranged in a unique way so that that it is transparent and allows light to enter unaffected into the cat’s eyeball.

The colored portion of the eye is known as the iris. A cat can open its iris very wide and its purpose is to let in as much light as possible. The back of the eye is known as the retina. A cat’s retina is composed of two major types of cells called rods and cones. These rods and cones are light sensitive. Rods are responsible for magnifying light impulses. The cat has an increased number of rods compared to humans. In humans, four out of five light sensitive cells in our retinas are rods. In cats twenty five out of twenty six cells are rods.

Cats also have a well developed mirror like layer located in the back of their eye. This is called tapetum lucidum. A number of animals besides cats, such as raccoons and deer have this as well. This is what makes their eyes glow in the dark when you shine headlights on them. When there isn’t a lot of light available, the cat’s tapetum lucidum reflects any light available back towards the front of the eyes. This is pretty cool, because it is almost like its allowing the cat to use the light twice to see better. Bottom line, because they are naturally nocturnal animals meaning they sleep during the day and are awake at night, cats are built to be able to see well even when there isn’t much light provided.