The way in which cats drink is very different to how dogs drink. In fact there is a link between how a cat drinks and its ability to maintain perfect balance (read more about this in the next paragraph).
An article from the journal Science reveals that cats extend their tongues towards their drinking bowl, but such that the tip of their tongue is slightly curled backwards. Thus, the top part of their tongues reaches the liquid first (Brehm, 2010).
Researchers from Princeton and Virginia Tech have found that the top of a cat’s tongue is the sole thing that touches the liquid.
This means that cats do not dip their tongues when they drink. In fact, the tip of their tongue barely touches the water.
When cats draw their tongues back, a column of liquid forms between it and the water surface.
As cats close their mouths, they pinch off the column of liquid (or at least the part of their tongue that temporarily holds the liquid). This is the reason why cats keep their chins dry while and after drinking.
The Role of Inertia and Gravity In How A Cat Drinks
Through liquid adhesion, some of the liquid is left on the cat’s tongue. The moment a cat draws back its tongue, the fluid that is supposed to follow it gets pulled back down toward the drinking bowl.
Such split-fraction shift of inertia to gravity is not visible to the naked eye, but the cat seemingly and instinctively knows when this change happens.
There is, however, a slight difference as to how domestic cats and big cats lap water.
On average, domestic cats lap four times per second, while big cats do so more slowly.
Researchers from the Massachusetts Institute of Technology (MIT) also concluded that the size and speed of the cat’s tongue contribute to the calculation of the ratio between inertia and gravity, at least to identify a perfect balance.
Theories, experiments, and mathematical formula also establish that the amount of liquid that a cat’s tongue captures depends on its speed and size.
A Well-Controlled Drinking Mechanism
Roman Stocker, a biophysicist from MIT, watched his cat Cutta Cutta drink from a water bowl.
He recorded the cat’s drinking behaviour with a high-speed camera and saw that indeed, this pinpoint lapping helps cats keep the balance between inertia and gravity. Stocker adds that a cat’s lapping is “delicate and well-controlled”.
To further gain insights into this mechanism, Stocker and his staff created a robotic cat’s tongue from a glass disk.
The disk moved up and down, mimicking the movement of a real tongue.
The experiment not only proved how cats could balance inertia and gravity, but also how cats seem to know the speed required for the lapping.
The Importance of this Research
These findings are of use to veterinarians, physicists, and cat enthusiasts.
It is also a significant breakthrough in robotics. According to Jeffrey Aristoff of Princeton University, the experiment on cats may be used by engineers working on “soft robots,” as well as those who are entertaining the possibility of creating robots that can walk on water.
Moreover, the experiment provides a clear explanation of fluid mechanics. To illustrate, Aristoff used the image of a shower and hot water. Suppose the steam rises in the hot shower; the inside of the shower curtain will flutter in towards you.
The dynamics between pressure and motion is akin to the dynamics involved when a cat drinks water. It also helps to understand that cats do not like getting their whiskers wet, lest they get whisker fatigue. This fact may also account for how carefully they drink.
