Cats love to groom themselves almost as much as they love to sleep, spending up to one-quarter of their waking hours cleaning their fur. The secret to their self-cleaning success? The spines on their tongues are curved and hollow-tipped, according to a paper published today in the journal PNAS. These tiny spines, called papillae, can transfer large amounts of saliva from mouth to fur, which not only cleanses Fluffy down to her skin but also lowers her body temperature as the saliva evaporates.

“A cat tongue works like a very smart comb,” says David Hu, a bioengineer at Georgia Tech and senior author of the new paper.

The results don’t just provide insight into how one of the world’s most popular