I'm Marlin Perkins and this is Mutual of
Omaha's WILD KINGDOM.
Did I fool you? Actually my name is Happy and I
have some scientific information today for all you readers that
think that cats are just dumb animals that drink by lapping up
liquids.
When we're very young, our moms teach us all
about surface tension and inertia and gravity and lots of physical
science principles that we need to know. You thought cat-like
reflexes just happened by magic? Recently some curious scientists at
some Big Name Universities studied how cats drink. Here's the
interesting part of the study:
Study reveals the subtle dynamics
underpinning how cats drink (w/ Video)
(PhysOrg.com) -- Cat fanciers
everywhere appreciate the gravity-defying grace and exquisite
balance of their feline friends. But do they know those traits
extend even to the way cats lap milk?
Researchers at MIT, Virginia Tech and Princeton
University analyzed the way domestic and big cats lap and found that
felines of all sizes take advantage of a perfect balance between two
physical forces. The results will be published in the November 11
online issue of the journal Science.
It was known that when they lap, cats extend their tongues straight
down toward the bowl with the tip of the tongue curled backwards
like a capital "J" to form a ladle, so that the top surface of the
tongue actually touches the liquid first. We know this because
another MIT engineer, the renowned Doc Edgerton, who first used
strobe lights in photography to stop action, filmed a domestic cat
lapping milk in 1940.
But recent high-speed videos made by this team clearly revealed that
the top surface of the cat's tongue is the only surface to touch the
liquid. Cats, unlike dogs, aren't dipping their tongues into the
liquid like ladles after all. Instead, the cat's lapping mechanism
is far more subtle and elegant. The smooth tip of the tongue barely
brushes the surface of the liquid before the cat rapidly draws its
tongue back up. As it does so, a column of milk 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 liquid column, it turns out, is created by a
delicate balance between gravity, which pulls the liquid back to the
bowl, and inertia, which in physics, refers to the tendency of the
liquid or any matter, to continue moving in a direction unless
another force interferes. The cat instinctively knows just how
quickly to lap in order to balance these two forces, and just when
to close its mouth. If it waits another fraction of a second, the
force of gravity will overtake inertia, causing the column to break,
the liquid to fall back into the bowl, and the cat's tongue to come
up empty.
While the domestic cat averages about four laps per second, with
each lap bringing in about 0.1 milliliters of liquid, the big cats,
such as tigers, know to slow down. They naturally lap more slowly to
maintain the balance of gravity and inertia.
