If you've ever wondered how cats lap their milk so elegantly (and who hasn't?) you're in luck.
A team of researchers has discovered the subtle balance of inertia and gravity required for felines to draw cream into their mouths without spilling a drop.
Apparently, the key is to keep the back of the tongue dry.
Cats don't use their tongues like ladles, as dogs do. Instead, cats dip their tongues straight into the bowl with the tongue curled backward. Once the tongue reaches the surface of its milk, the cat draws it up up so quickly, about four times per second, that the liquid's inertia causes it to stick to the tongue. The cat then quickly closes its mouth for a clean, quick drink.
"The cat instinctively knows just when this delicate balance will change, and it closes its mouth in the instant before gravity overtakes inertia," the researchers found.
Bigger cats like tigers and cheetahs lap more slowly to make up for the greater surface area, and thus, higher liquid inertia.
The self-styled "lapping research" began three years ago when Roman Stocker, a biophysicist at Massachusetts Institute of Technology, became fixated watching his cat Cutta-Cutta drink his morning milk without making a mess. Stocker teamed up with scientists at Princeton and Virginia Tech to solve the mystery.
The project was done "without any funding, without any graduate students and without the usual apparatus that science is done with nowadays," Stocker said in a statement.
"Our process in this work was typical archetypal, really of any new scientific study of a natural phenomenon. You begin with an observation and a broad question 'How does the cat drink?' and then try to answer it through careful experimentation and mathematical modeling," added fellow MIT researcher, Pedro Reiss.
Click here to watch a high-speed video of Cutta-Cutta in action, plus footage of a robot version of a cat's tongue that allowed the scientists to study the physics behind this elegant table manner.