Cat Got Your Tongue: The Feline Tongue's Unique Shape and Flexibility

Watching the antics of cats may be a form of relieving stress for most people, but a group of researchers has taken this pastime one step further by becoming the first group to 3-D print a cat tongue mimic at 400 percent scale.

Alexis Noel, a doctoral candidate in mechanical engineering, was watching her cat lick a thick, microfiber blanket and noticed its tongue get immediately stuck. Noel, who works in the Hu Biolocomotion Lab at Georgia Tech, decided to study the odd "spines" she noticed while helping to disentangle her cat.

Upon close inspection, a cat's tongue is riddled with tiny Velcro-like hooks and as it glides over fur, these hooks catch tangles and snags. "When the cat's tongue hits a snag, it pulls on the hooks, which rotate to penetrate the snag even further. Like a heat-seeking missile for snags, the hook's mobility allows the cat to better tease tangles apart," explained Noel.

"A typical hairbrush has spines that stick straight out. When hair collects on the brush it forms a thick mat that must be removed by hand," Noel continued. In comparison, the cat's flexible spines make it easier to clean. When not in use, the spines on a cat tongue lie nearly flat against its surface, like overlapping shingles.

By using macro- and high-speed videography equipment, Noel and her colleagues were able to zoom in and study the unique shape and flexibility of the tongue spines during grooming. "In terms of shape and sharpness, it reminds me of cat claws. And this opens yet another question of why all claws are shaped so similarly," Noel said. "Both the cat tongue and mimic are very good at cleaning and removing tangles in fur samples. We also discovered that the cat tongue is self-cleaning it's easy to remove hair beneath the spines by simply brushing the tongue from tip to end."

Noel's findings, which she recently presented at the 69th Annual Meeting of the American Physical Society's Division of Fluid Dynamics (DFD) in Portland, Oregon, may have very important implications in the field of soft robotics where scientists are still searching to find ways for soft materials to grip surfaces. Noel added, "The flexibility of cats' tongue spines may have broad-reaching applications from an easy-to-clean hairbrush to wound cleaning within the medical field."