In a new study, scientists from Georgia Tech looked closely at the spines that make the tongues of cat feel like a sandpaper.
Cat Tongue Spines
Cat tongues have plenty of uses: they groom, they spread body oils, they remove fleas and dirt, and they improve circulation. Cat owners are well aware that the furry creatures spend an exorbitant amount of time — up to a quarter of their waking lives — licking themselves.
To human skin, a lick from a cat does not feel as pleasant. Cat tongues notoriously have the texture of sandpaper. However, researchers argued that cat tongue is not like sandpaper at all. Instead, these feline friends might have the world's most efficient hairbrush.
Using a 3D-printed model, researchers revealed that cat tongues are covered in tiny backward spines made of keratin, the same material that makes up human nails. Moreover, during a single grooming sweep, the cat tongue moves in four different directions that adapt and easily detangle fur.
Alexis Noel, the lead author of the study, explained that when a spine called papillae encounters a knot in the fur, it snags and pull, making it a lot more sturdy and effective than a normal human hairbrush.
"As the snags pull on the hook, the hook rotates, slowly teasing the knot apart," said the Ph.D. candidate in mechanical engineering. "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."
Moreover, the spines on the tongues of cats are very flexible. They lay flat when the cat is not grooming, allowing the fur collected to slide right off.
In addition, researchers found that papillae are not cone-shaped, but scoop-shaped and hollow. This allows the cat tongue to hold saliva and distribute the cleansing liquid onto the fur.
Cats Inspiring New Technologies
Noel was inspired to focus on cat tongue for the study after she had watched her own pet lick a blanket and get stuck. The researcher revealed that there are plenty of things to learn from the creatures. She said that the study, published in the journal Proceedings of the National Academy of Sciences, can add new insights into the field of soft robotics. She also explained that their findings could contribute to the development of new technologies in cleaning various things such as carpets or even wounds.
Noel and her team are already in the process of getting their 3D-printed cat tongue patented. They are also planning to talk to various professionals for possible uses of their findings, including possibly developing a new kind of hairbrush.