Why do animals lick water with their tongues?

Because cats and dogs have many teeth, their mouths are relatively large, and their mouths extend to the front of their cheeks. The mouth is so open that it can't absorb water without the help of lips and complex facial muscles. So roll up the water with your tongue instead of licking it.

Scientists carefully observed the drinking movements of cats and dogs with high-speed photography and found that they were not actually licking. They put their tongues into the water first, then the tip of the tongue bends backward and quickly retracts their tongues, which will suck some water into their mouths.

This "suction" takes advantage of the surface tension of water. In this way, cats and dogs can actually drink water quickly.

Extended data:

The face and lips of human beings (including some primates) can form a perfect straw shape, so absorbing water is much more efficient than licking water.

Compared with humans, drinking water is more challenging for cats. They drink water from a flat container. If people's hands are tied, because people's cheeks can form a proper closed space, they can still suck water into their mouths. Pigs, sheep and horses have the same drinking ability as people, but cats and dogs don't.

Because their gills can't stretch far enough forward, they can only find new licking methods.

Xinhuanet-Why do cats and dogs lick water with their tongues?