You might have noticed how cats delicately lap up milk, while dogs will head over to
a water dish and sloppily splash all over your floor.
事实上 “猫和狗的口水规则” 是有一些有趣的物理理论
Turns out, there’s some interesting physics to back up the phrase, “cats rule and dogs
That’s because these pets have to use their tongues to get liquids into their mouths,
fighting against the effects of gravity.
And, according to a couple research studies, cats and dogs have slightly different techniques
that do or don’t make a splash.
You and I can sip our milkshakes and soups thanks to suction.
And animals like horses, pigs, and sheep can suck up their water, too.
And that’s because we all have complete cheeks, which means we have muscles and tissues
that let us seal our mouths and create a partial vacuum.
Basically, you can make a pocket of lower air pressure in your mouth, so the water you’re
trying to drink gets pushed up by the higher-pressure outside air.
And that’s suction.
But cats and dogs don’t have cheeks like ours.
Like lots of predatory mammals, they have incomplete cheeks, which lets them extend
their jaws wider to chomp down on their prey.
But they /can’t/ create that partial vacuum and suck up liquid.
Instead, they use their powerful tongues to create columns of liquids like water or milk,
and lap it up.
Using slow-motion video, different groups of researchers have tried to figure out the
physics behind the tongue movements of cats and dogs.
One study found that cats lower the tips of their tongues to just barely touch the surface
of the water.
Then, they quickly retract their tongues at speeds of almost 80 centimeters per second.
The water molecules stick to the cat’s tongue thanks to adhesive forces, and stick to each
other because of cohesive forces.
And this creates a column of water for a split-second, fighting against the force of gravity.
然后在舌头减速回到嘴里后 猫会把嘴闭上不让水流出来 猫吞下水之后继续重复以上动作
Then the cat slows down its tongue, closes its mouth to trap some of the water. Swallow and repeat.
在另一方面 根据一项研究 狗在喝水上比猫要更
Dogs, on the other hand, are a little more gung-ho than cats, according to a separate
These researchers found that dogs splash their tongues deeper into water bowls, curl them
into more of a ladle-shape, and then can retract them at speeds of 700 centimeters per second
This means more of a dog’s tongue is touching the water, so dogs end up making a bigger,
messier water column before they clamp their mouths shut.
狗狗越大只 舌头也越大 意味着喝水碗附近也更乱
The larger the dog, the larger the tongue, and the larger the splash.
So next time your dog makes a mess at the water bowl … you can blame physics.
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