Each lick of a cat tongue releases one tenth an eyedropper of saliva from hollow, scoop-shaped cones called papillae. That’s one of the findings from a study released today in the journal PNAS that examines the cat tongue in unprecedented detail.

While the sharp rasp of a cat’s lick is no mystery, the hollow nature of some of the cones on the tongue surface is new to science. The two Georgia Institute of Technology researchers who conducted the study are calling them cavo papillae, and they were found in all six cat species used in the study, ranging from domestic kitty to lion.

The extreme cooling effect of these saliva deposits was another startling finding, with thermoscans showing an impressive temperature drop of 31 degrees F (17 degrees C) just after grooming. Cats can groom themselves for up to a quarter of their waking hours, and it’s estimated to be responsible for around a third of their moisture loss.

This is the surface of a cat's tongue. Rigid, hollow papillae near the tongue tip are shown on the right, while soft, conical papillae near the throat are shown to the left. (Credit: Alexis Noel)

This is the surface of a cat’s tongue. Rigid, hollow papillae near the tongue tip are shown on the right, while soft, conical papillae near the throat are shown to the left. (Credit: Alexis Noel)