Anyone who has ever received a loving lick from a cat knows quite well that scratchy, sandpaper feeling. Recently, PBS explored the science behind the unique texture of a feline's tongue—and it's bound to fascinate every cat parent.
Researchers took a deeper look at the cat tongue, which is covered in tiny spines called papillae. "They’re made of keratin, just like human fingernails...The individual spines are even shaped like miniature cat claws with a very sharp end," explained Georgia Tech researcher Alexis Noel. "They’re able to penetrate any sort of tangle or knot, and tease it apart."
Noel took an interest in learning more about cat tongues when, as she told PBS, her family's cat got his own tongue stuck on a blanket while he was grooming himself.
After that incident, she conducted her research by creating a 3D-printed cat tongue model. In her experiments, she dragged the tongue across a patch of fake fur, and discovered that a tongue was easier to clean when it went in the same direction as the papillae. The hairs would come off easily, as opposed to, say, a brush, which requires you to pull hairs out.
The most surprising thing the researchers found in their studies was "how flexible the cat tongue spines are when grooming," Noel told petMD. "When the spine encounters a snag, the spine rotates and teases that tangle apart. We are also surprised to discover the unique shape of the cat tongue spines and their similarity to claws. Our 3D-printed cat tongue mimic helps us visualize the detangling mechanics between spine and fur at a much larger scale."
The research also allowed Noel to figure out exactly why her family's cat got stuck in the blanket. "Cats are used to grooming their own fur, which is secured at the hair root to their skin and free at the other end," she described. "The microfiber blanket which Murphy licked was composed of small loops, where each thread was secured at both ends. When cats encounter a tangle in their own fur, their saliva and the spine flexibility helps to loosen and break any snag. I think Murphy was expecting that he could 'groom' the loops but couldn't."
Noel—who, along with fellow researchers, is currently studying bobcat and tiger tongues—noted that a cat's tongue is a "multipurpose tool" that is used not only for grooming purposes but also eating. (She added that, like fingernails, the tips of the spines are slightly curved, and the keratin in them helps strengthen them for various uses.)
"The micro-spines on the tongue allow cats to clean their fur of unwanted scents (such as blood), redistribute protective oils, and remove any matting," Noel said. "We hypothesize that the spines are uniquely shaped to penetrate muscle and tear chunks of meat, much like a cheese grater."
So, the next time you see your cat grooming himself, other cats, or even you, remember that there's not only a trust there, but also a downright amazing function.
Learn more about cat grooming here.
Image via Shutterstock