They are in light sleep 50 percent of the time. Cats are the only animal that walk on their claws, not the pads of their feet. Cats step with both left legs, then both right legs when they walk or run. The only other animals to do this are the giraffe and the camel. In ancient Egypt, entire families would shave their eyebrows as a sign of mourning when the family cat died.
Cats have five toes on each front paw, but only four toes on each back paw.
Cats have true fur, in that they have both an undercoat and an outer coat. Newborn kittens have closed ear canals that don't begin to open for nine days. When the eyes open, they are always blue at first. They change color over a period of months to the final eye color. Most cats have no eyelashes.