Domestic cats are known for their grooming habits. They may devote 24 percent of their waking hours to grooming. This cleaning habit owes its efficiency to the cat’s amazingly equipped tongue.

 Consider: The cat’s tongue is covered with 290 papillae, tiny backward-facing spines that are about as stiff as your fingernail. Each papilla has a groove that instantly picks up saliva when the tongue is drawn into the cat’s mouth. As the cat licks its fur, the papillae reach down through the hairs and release the saliva onto the skin.

 A cat’s tongue can transfer about 48 milliliters (1.6 oz) of saliva to its skin and fur every day. This saliva contains enzymes that break down contaminants. Additionally, as the saliva evaporates, it provides almost one quarter of the cat’s body cooling—essential because cats have few sweat glands.

 If one of the papillae hits a tangle, it swings deeper into the fur, which substantially increases the force and pulls the snag loose. The tips of the papillae may also stimulate the skin when the cat is grooming. Researchers imitated the properties of the cat’s tongue when they made an experimental hairbrush. This brush combs hair with less force than a standard hairbrush and can be cleaned more easily—plus it unsnarls tangles. The researchers believe that the cat’s tongue could inspire the development of better ways to clean hairy and shaggy surfaces. It may also be used to improve methods of applying lotions or medications onto skin that is covered with hair.

 What do you think? Did the cat’s tongue evolve? Or was it designed?