Every time you watch your cat drink, you're watching an incredible display of physics. Cats are known for being beautiful and graceful, but even their drinking is a nearly miraculous balance of forces so compelling that scientists have studied exactly how the process works.
Researchers have analyzed how cats drink for years. Scientists at MIT in the 1940s filmed a cat drinking milk and studied the footage for years. From this video, it was thought that cats extend their tongues straight down in the bowl and curl the tip of their tongue backwards. The bit of tongue that touches the milk first is the top of the tongue.
The development of high-speed camera technology gave us new insight, and a new way to look at cats. It turns out that catss don't dip their tongues in their water or milk like dogs dog. Dogs drink using their tongue more like a ladle. Cats have a totally different mechanism – one that really seems quiet inefficient.
The high-speed footage showed that the only part of a cat's tongue that touches the water is the top. , Denise Brehm, a representative from MIT's department of Civil and Environmental Engineering, described the process like this: "The smooth tip of the tongue barely touches the surface of the liquid before the cat draws its tongue back up. As it does so, a column of liquid forms between the moving tongue and the liquid's surface. The cat then closes its mouth, pinching off the top of the column for a nice drink, while keeping its chin dry."
The study continues, explaining how the seemingly inefficient process is really quite effective. "When the cat's tongue touches the liquid surface, some of the liquid sticks to it through liquid adhesion, much as water adheres to a human palm when it touches the surface of a pool. But the cat draws its tongue back up so rapidly that for a fraction of a second, inertia - the tendency of the moving liquid to continue following the tongue - overcomes gravity, which is pulling the liquid back down toward the bowl. The cat instinctively knows just when this delicate balance will change, and it closes its mouth in the instant before gravity overtakes inertia. If the cat hesitated, the column would break, the liquid would fall back into the bowl, and the tongue would come up empty."
Interesting stuff! Who could have ever thought that such a simple act was filled with such incredible physics?
Drinking in slow motion
Check out this video