Whether you’ve got a big ol’ lumberjack beard or a pencil-thin mustache,
if you have facial hair, you might refer to it as your “whiskers.”
But that is not what they are.
The fact is, humans don’t have whiskers.
True whiskers—like those on your dog or cat—are far more special
than any human facial hair.
触须非常灵敏 能帮助动物捕食 感受风向
Whiskers are acutely sensitive and can help creatures hunt, sense the direction of the wind,
and find their way around in the dark.
事实上 这些触须作用很大 几乎所有的哺乳动物都有触须……
In fact, they are so useful, nearly all mammals have them…
we’re just one of the rare exceptions.
那么 触须和你下巴上的胡茬 到底有什么不同呢？
So, what makes whiskers different from the stubble on your chin?
Well, whiskers are what scientists call vibrissae.
And they are similar to regular hair … they’re made out of the same protein, keratin.
但是触须通常更粗 更硬 更加重要
But whiskers are usually thicker, stiffer, and more importantly, they grow out of
completely different kinds of follicles than your hairs do.
The follicles for vibrissae are deep in the skin, and they’re surrounded by pockets
of blood, which are connected to nerves.
Researchers think that these pockets of blood help amplify any vibrations that come through
the hairs to help make them extra-sensitive to touch.
当然 神经连接着大脑 大脑内部包含感觉皮质区
And the nerves, of course, lead up to the brain, where huge sections of the somatosensory
cortex are devoted to making sense of all the tactile information
that the whiskers are picking up.
Now, whiskers can be found anywhere on an animal’s body, but the most common spot
is on the face, especially around the mouth or eyes, where they come in two main types.
The long hairs we usually think of as “whiskers” are called macrovibrissae,
and they can be moved voluntarily.
But there are also shorter, stubbier whiskers, usually right under the nose, called microvibrissae.
Many animals, like rats or mice, have both kinds.
And in those creatures, it’s thought that the big ones are used for spatial tasks,
while the little ones are more important for recognizing certain objects.
If you can move your big whiskers, like a rat does, you can actually get lots of really
valuable information about the space around you … almost like seeing, but with your hair.
This behavior actually has a name—aptly enough, it’s called whisking.
比如说 一只大鼠进入一个陌生的环境它将缓慢地移动 反复地抖动触须
For example, if a rat is new to an area, it will move slowly, flicking its whiskers back
and forth, letting them sweep over a broad area to get a good sense of the surroundings.
But if a rat already knows the space, it will move more quickly, and whisk over a smaller
area just to make sure it doesn’t run into anything.
And if a rodent is especially interested in something, it will increase the speed of its
whisking to get a higher resolution sense of what the thing is.
Other animals use their whiskers for more nefarious purposes…
at least, if you’re a prey animal.
The tiny etruscan shrew, for example, uses its whiskers to find and capture insects nearly
as large as itself, even inside dark tunnels.
海豹也一样 它们会使用触须捕食 甚至可以凭借触须
Seals, too, use the tactile hairs to hunt, and have whiskers so sensitive that they can
actually sense fish breathing.
Biologists think that’s because seals have as much as ten times the number of nerve endings
per whisker follicle that land animals have.
OK, so you get that whiskers are super-useful,
and on the right animal, they can be downright dashing.
So in that case, why don’t we have them?
Well, we probably did at one point.
Or, at least, our ancestors did.
Whiskers are thought to have been an important adaptation in early mammals, including primates.
But then, around 800,000 years ago, we appear to have lost the bit of DNA
that allows for true whiskers.
However, our distant cousins—the other great apes—still have it, and you can see their
whiskers if you look closely.
这些触须没有猫的触须那么长 那么显眼但是黑猩猩 大猩猩 红毛猩猩
They are not the big flashy whiskers your cat has, but chimps, gorillas, and orangutans
all have microvibrissae all around their mouths and eyebrows.
There’s even evidence that some people today have vestigial muscles in their upper lips
that are leftover from when our primate ancestors had whiskers—
although, not all scientists are convinced about that.
不管怎么说 当今人类没有触须 依旧生活地很好
Either way, modern humans seem to have gotten along just fine without whiskers.
All that brain space that was dedicated to getting information from whiskers is now used
to map our sense of touch, with a big chunk going to our fingertips.
And we have pretty good visual systems for navigating, so we don’t have to feel our
way around with hairs.
所以 如果你想出门用触须感知周边 或拥有一对漂亮的“夜魔侠”版的触须
So, if you’re wishing you could go out for a nice whisking, or had a sweet set of whiskers
that could make you into like a real-life Daredevil, take heart.
Not having them is part of what makes you human.
But if you want to see me rocking some scientific cat ears,
check out our Talk Show about the brain with Dr. Amanda Duley.
There’s a link in the description.
I move them with my mind.