As many of you know I have crossed over. Mom promised that she would restart my blog and publish at least once a week. I suggested with some claws that she republish a story of mine. I figured it would get the ball rolling. So, this is mom’s adaptation. Be kind. She talks and thinks like a chemist which is a foreign language although I think she speaks English.
Science of Cat Lapping
The science of how animals drink is intriguing. Some animals like pigs and horses use suction combined with their tongue to pull liquid into their mouths like how we use straws. Animals such as dogs and cats, cannot create suction (after weaning) and must use their tongue to bring liquid to the mouth.
I have always wondered why dogs dribble all over the floor when they drink water. I tell you, I can’t stand that I have to walk around all that dog drool. So far all we know is that dogs don’t drink like horses. I decided to investigate further.
A slow motion shows that dogs curl their tongues backwards forming a cup as the tongue enters the water. The tongue continues to curl, bringing water into the mouth. That tongue can deliver a lot of water. I finally understood why all the water in the dish ended on the floor! Dogs can’t help but be sloppy with that approach.
Unlike dogs, cats do not curl their tongues to form a cup. Cats are elegant lappers. It has long been presumed that the rough surface of our tongues due to filiform papillae is responsible for how we get liquid into our mouth.
However, researchers at MIT, Virginia Polytech and Princeton showed that this is not a likely scenario. High-speed imaging was used to observe what we do. Cats extend their tongue curling slightly toward their chest. Only the smooth surface of the tongue tip touches the liquid, the tongue does not penetrate the surface at all. Instead, the tongue is pulled toward the mouth with a column of liquid following. Since only the curved tongue tip touches the surface, the rough papillae on the tongue are not involved. According to Science Magazine, the mouth is then closed, capturing some of the liquid. What is astounding is that cats’ tongues can perform this feat four times per second, moving at a rate of one meter (39 inches) per second.
The liquid column is quite interesting, and is formed by two competing forces, inertia and gravity. This action creates a surface tension phenomenon such that the liquid follows the lapping motion. The liquid is kept in the mouth until it is swallowed after several lapping cycles. Viscosity (thickness) of the liquid was not a major factor for the lapping process.
These are remarkable discoveries, and it is mind boggling that it has taken all these years to figure out how we cats drink. I will sum up by saying, “Cats rule. Dogs drool,” and I have science to back me up!
Republished posthumously. Originally published:
http://www.animaltimes.com/2011/02/cat-lapping-science; Mon, 07 Feb 2011