SE-Ed: Why Do We Get Goosebumps?

Have you ever stepped outside on a freezing morning?

你有没有在寒冷刺骨的早晨走出家门过？

Suddenly, your arms are covered in tiny bumps!

突然，你的手臂上冒出了许多小疙瘩！

The same thing can happen during a sad film,

看悲伤的电影时也可能这样，

or when your favourite song starts to play.

或者当你最喜欢的歌响起时。

We call them goosebumps. But what are they, exactly?

我们管它叫鸡皮疙瘩。但它到底是什么呢？

Every hair on your body grows out of a tiny tube.

你身上的每一根毛发，都是从一根微小的管子里长出来的。

At the bottom of each one, there's a very small muscle.

每根管子的底部都有一块非常小的肌肉。

When you get cold, this muscle suddenly tightens.

当你感到冷时，这块肌肉会突然收紧。

It pulls the hair straight up,

它把毛发拉得直立起来，

and it pushes up the skin around it too.

同时也把周围的皮肤顶起来。

Thousands of tiny bumps appear at the same time!

成千上万个小疙瘩同时冒了出来！

In English, we say our skin looks like a goose's.

英语里，人们说我们的皮肤像鹅皮。

In French, Spanish and Vietnamese, it's chicken skin!

而在法语、西班牙语和越南语里，它叫鸡皮！

Either way, a bird's skin has the very same bumps.

无论哪种说法，鸟的皮肤上都有一模一样的小疙瘩。

So why do our bodies do this at all?

那么，我们的身体为什么会这样呢？

Scientists think the answer is millions of years old.

科学家认为，答案要追溯到几百万年前。

Our early ancestors had much thicker hair than we do.

我们早期的祖先，毛发比我们浓密得多。

When their fur stood up, it trapped a layer of warm air.

当它们的毛竖起来时，就能锁住一层暖空气。

It worked like a free winter coat!

就像一件免费的冬衣！

Sadly, we've lost most of that hair,

可惜，我们已经失去了大部分毛发，

so goosebumps don't keep us very warm today.

所以如今起鸡皮疙瘩已经没法让我们暖和多少了。

Fear can give you goosebumps too.

害怕也会让你起鸡皮疙瘩。

Look at a frightened cat, and you'll see why.

看看受惊的猫，你就明白了。

Its fur stands up, so it looks bigger and scarier.

它的毛竖起来，看起来更大、更吓人。

A porcupine does the same thing with its sharp quills!

豪猪也会用它尖利的刺做同样的事！

Our hair is far too short for this trick,

我们的毛发太短，玩不了这一招，

but our bodies still try it when we're scared.

但我们害怕时，身体还是会试一试。

But why do we get them from music?

那为什么听音乐也会起鸡皮疙瘩呢？

Strong emotions send the body the same signal as cold.

强烈的情绪会向身体发出和寒冷一样的信号。

That's why a beautiful song can give you chills.

所以一首动人的歌会让你起鸡皮疙瘩。

A few people can even make goosebumps on purpose!

少数人甚至能故意让自己起鸡皮疙瘩！

And in 2020, scientists at Harvard found something new!

2020年，Harvard的科学家有了新发现！

In mice, the nerve behind goosebumps also helps new hair grow!

在小鼠身上，引起鸡皮疙瘩的神经还能帮助新毛发生长！

So these tiny bumps may still be useful after all.

所以，这些小疙瘩说不定还是有用的。

Next time you shiver, say thank you to your ancestors!

下次打寒战时，记得谢谢你的祖先！