Study reveals mechanics of dogs drinking
A study by the Virginia Tech College of Engineering has revealed that dogs do not drink water in the same way that cats do.
Published in Proceedings of the National Academy of Sciences, the study shows that dogs are able to accelerate their tongues much faster than cats, plunging them into the water and curling them downwards toward their lower jaws.
The researchers observed that dogs quickly retract their tongues and a column of water forms and rises into their mouths. They also curl the underside of their tongues to bring a small ladle of water upwards.
Conversely, cats were found to lightly touch the surface of the water with their tongues, usually never fully immersing them. When their tongues rise into their mouth, liquid sticks to the upper side, forming an elegant water column.
The researchers say that the idea that dogs are messy drinkers comes from the backward curl of the tongue, which increases the size of the column of water, enabling dogs to drink more per lap than with a straight tongue.
“This was a basic science study to answer a question very little was known about — what are the fundamental mechanics of how dogs drink?” said Sean Gart, a graduate student in biomedical engineering and mechanics.
“Cats tend be viewed as neater, dogs are messier, but dogs really have to accelerate their tongues to exploit the fluid dynamics of the water column.”
David Hu, an associate professor of mechanical engineering and biology at the George W. Woodruff School of Mechanical Engineering at Georgia Tech, added: “This is nice work and great outreach that gets people interested in science by taking an everyday activity that people see all the time and showing how it really works,”
“It was surprising to me that dogs actually accelerate their tongues. When we drink, it is basically at a steady speed, but dogs are accelerating their tongues to between 2 Gs and 4 Gs. The dog moves its tongue at a higher acceleration than a rocket.”