Stop comparing your cat’s tongue to sandpaper. It’s actually much more like a hair brush covered in spines shaped like claws and made of keratin, the same material as your fingernails.
Researchers at Georgia Tech have shown that a cat’s tongue moves in four directions, acting like a super de-tangler, according to The Washington Post. In a “single grooming sweep,” a cat’s Velcro-like tongue tackles the toughest knots. When not in lick-mode, the spines lie flat.
“When the tongue glides over fur, the hooks are able to lock onto tangles and snags,” author Alexis Noel, a PhD candidate in mechanical engineering, told the Washington Post. “As the snags pull on the hook, the hook rotates, slowly teasing the knot apart. Much like claws, the front of the spine is curved and hook-like. So when it encounters a tangle, it is able to maintain contact, unlike a standard hairbrush bristle, which would bend and let the tangle slide off the top.”