As all cat lovers know well, felis domestica is a marvel of balance, subtlety and other hidden elegances.
Prepare to learn of another remarkable attribute: Four researchers have painstakingly filmed, analyzed and determined how it is that a cat can drink water while (unlike a dog) keeping its chin and whiskers pleasingly dry.
The answer involves an exquisite demonstration of physics, in which the cat, in effect, balances the forces of gravity against the forces of inertia, and so quenches its thirst.
“What we found is that the cat uses fluid dynamics and physics in a way to absolutely optimize tongue lapping and water collection,” said Jeffrey Aristoff, now at Princeton University but who was one of the four researchers who began their studies out of curiosity at the Massachusetts Institute of Technology.
The study was published Thursday by the journal Science.
While dogs curl their tongues to collect the water and then pull up what they can, cats barely touch the liquid with the tips of their tongues. A slight backward curl of the tip encourages liquid to adhere to the smooth top of the tongue, but that’s not how the water rises.
Rather, the water on the tongue, combined with the low pressure created by the slightly curled tongue moving back up, creates a momentary stream into the mouth. The cat then snaps its mouth shut and the water is captured before the countervailing force of gravity pulls it down. A typical house cat, the team found, can make four of these mini-streams per second.
