A crocodile’s thick, rough skin looks like an impenetrable suit of armor. But the croc’s skin actually confers a delicate sense of touch that’s among the most acute in the animal kingdom. That’s according to a study in The Journal of Experimental Biology. [Duncan B. Leitch and Kenneth C. Catania, Structure, innervation and response properties of integumentary sensory organs in crocodilians]

Researchers found that the small, spotted bumps that cover the skin of crocodiles and alligators are chock full of nerve endings that are exquisitely sensitive to pressure and vibration. Even more sensitive than human fingertips.

These touch-sensors are especially good at detecting the vibrations caused by tiny water ripples—something that may help the animals locate swimming prey. And the most sensitive areas were found near the face and teeth—likely helping the animals to identify and manipulate objects with their mouths: crucial for crocodile females who must delicately carry and protect hatchlings in their powerful jaws. 

Researchers say they’ve known about the spotted bumps for years, but because of crocodile skin’s tough, armorlike appearance, they simply assumed their function was something other than feeling. The lesson? Never judge a croc…by its cover.

—Gretchen Cuda Kroen

[The above text is a transcript of this podcast.]