What scientists are learning about cats' amazing, Velcro-like tongues

Anyone who’s ever watched a cat patiently licking away at its fur knows that the scratchy feline tongue makes for an efficient grooming tool. It rakes right through tangled manes even better than a hairbrush. Now, some scientists are trying to harness that natural ability for a range of surprising uses, from enhanced robotics to medical devices to new types of hairbrushes. 

Studying cat tongues might not seem like a promising jumping off point for new innovation, but for Georgia Institute of Technology doctoral candidate Alexis Noel, a life spent around the feline companions led to inspiration for her current research. 

Noel and her team honed in on the surprisingly complex surface and function of cats’ tongues, filming their movements in incredible detail with high-speed cameras as the animals moved cat food around on a fur mat. The film revealed how tiny, claw-like spines that line a cat’s tongue can dig into objects, like clumps of fur when a cat licks itself, and similar to Velcro, grip onto objects and rip them away. 

The researchers ended up making a 3D-printed model of a cat’s tongue — four times greater than life-size — to experiment with the tongue’s physiology.

Ultimately, this deep dive into cat tongues could pave the way for the development of new technologies that mimic its natural Velcro-like function.

Noel and her colleagues presented their research on Nov. 21 at the meeting of the American Physical Society’s Division of Fluid Dynamics in Portland, Oregon. In an email to CBS News, she explained how this unusual research project got its start.

“My whole life I have grown up with cats as household pets. I was home for a few days of break, watching TV with the family cats. Murphy, a 3-year-old male cat (short-haired breed, with tan stripes), decided that the couch blanket smelled tasty, and decided to give it a good lick. When I was done laughing at this curious cat, the scientist in me began to question how a soft, wet tissue could stick to something so easily,” Noel wrote. “After a few seconds of struggle, he figured out that he could detach his tongue by simply pushing his tongue into the blanket rather than pulling (de-hooking the blanket loops). During this time, I had been studying how saliva affects taste, and I had noticed a variety of mammals (cows, deer, tigers) having sharp spines on the surface of mammalian tongues. Once I got back to campus, it was an easy transition to studying rough cat tongues.”

Murphy would probably be surprised to see how influential his feline tongue could end up being in the booming field of robotics. Noel said her work could enable scientists to work on soft robotic designs — flexible robots that are made of bendable materials like rubber and elastic plastic. Until now, researchers haven’t been able to find efficient ways for these slippery robots to grip onto hard surfaces, but that could change if designs could effectively mimic cat tongues. 

In addition, this research could also lead to the development of different kinds of brushes and other cleaning tools.

“The first known hairbrush is dated back to 8,000 BC, with the first patent appearing in 1854,” Noel noted. “Since then, the hairbrush design really has not changed. We look to see how the cat tongue can be scaled to suit human hair, providing a novel design to the traditional hairbrush.” 

“This research may also have a variety of applications from new ways to clean deeply embedded dirt in your carpet to wound cleaning advances in the medical field to gripping mechanisms for rough terrain. In the field of soft robotics, the current application is unclear, but I look forward to perhaps collaborating with soft roboticists in the near future,” she wrote.

Right now, Noel and her colleagues are going to develop their cat tongue technology through Georgia Tech’s Innovation Corps (I-Corps), which helps National Science Foundation develop  potential “product opportunities” that could come out of their academic research, according to Georgia Tech’s website. 

“We plan to work with the GT I-Corps group to understand where this technology can best be applied in industry,” she added.