So, Dr. Stocker, from the Massachusetts Institute of Technology, decided to find out.
He, along with Pedro M. Reis, also of MIT, and Sunghwan Jung of Virginia Polytechnic Institute and Jeffrey M. Aristoff of Princeton University, conducted an experiment to find out the physics of cats lapping up water.
A summary of their work appears in an article within Science Express, a part of Science magazine.
It is entitled 'How Cats Lap: Water Uptake by Felis catus.'
They state, 'We show that the domestic cat (Felis catus) laps by a subtle mechanism based on water adhesion to the dorsal side of the tongue.'
And, 'A combined experimental and theoretical analysis reveals that Felis catus exploits fluid inertia to defeat gravity and pull liquid into the mouth.'
'This competition between inertia and gravity sets the lapping frequency and yields a prediction for the dependence of frequency on animal mass.'
Page two explains further, along with a video of a cat lapping up a liquid in slow-motion.