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You know, Squeaks and I spend a lot of time underground.
我和吱吱花了很多时间研究地下，
And that means we've made a bunch of squirmy little friends.
也就是说我们有了一群会蠕动的小朋友
If you've spent any time digging in the ground, you've certainly met them, too.
如果你有时间在地上挖一挖，也能遇到它们。
I'm talking about earthworms! These animals are super cool, and super hardworking, too!
我说的就是蚯蚓！这种动物非常厉害，也非常勤劳！
Let's see if we can get the dirt on these wiggly worms.
看看我们能不能从这些蠕动的小虫子身上弄到点儿泥土。
First of all, even though you often find earthworms outside,
首先，你经常在户外看到蚯蚓，
where you find insects like ants and beetles, earthworms aren't insects.
就像总能看到蚂蚁甲虫之类的昆虫一样，但蚯蚓并不是昆虫。
Can you spot the differences?
你能看出不同来吗？
Remember what makes an insect: six legs, three main body parts, and a hard exoskeleton.
想想昆虫的特征：六条腿，三节身体还有坚硬的外壳。
Our earthworm doesn't match that at all!
我们的蚯蚓与之完全不符。
Earthworms have smooth skin and a body made up of many small segments—
蚯蚓有光滑的皮肤，身体由许多段组成——
it kind of looks like they're covered in a lot of little rings.
看起来就像许多小圈包裹着它们。
And each segment has small hairs that are almost too tiny to see.
每一节都有许多细小到看不见的刚毛。
And even though they're long and skinny like snakes, they're not snakes!
它们像蛇一样又长又细，不过它们不是蛇。
Snakes have a skeleton, and earthworms don't. But they do have strong muscles.
蛇有骨骼，蚯蚓没有。但是它们有强健的肌肉。
In order to move, the earthworm squeezes its muscles together, which makes its body thinner and longer.
为了移动，蚯蚓收紧肌肉，让身体变细变长，
Then the earthworm uses those little hairs on its body to hold on to the soil around it, and pull itself forward.
然后用身上的刚毛勾住周围的泥土，再推动自己向前。
Have you ever seen a bird trying to pull an earthworm out of the ground?
你曾见过一只鸟努力将一只蚯蚓拉出地面的场景吗？
The worm can make it hard for the bird, because it can actually hang on to the dirt with those tiny little hairs!
这个过程对鸟来说很难，因为蚯蚓会用那些小刚毛勾住泥土。
Now, just like most animals, earthworms have a front end and a back end.
现在，像大多数动物一样，蚯蚓也有一个头部和尾部。
Up front, you'll find their mouth and a teeny tiny brain, about the size of a pinhead.
在头部，你会看到它们的嘴和细小的大脑，大约是针头大小。
But that little brain gets the job done.
那小小的大脑也会工作。
Earthworms are able to sense light and vibrations—so they know when to wiggle away!
蚯蚓可以感受到光和振动，它们知道什么时候该离开。
And when earthworms needs to wiggle away, where do they go?
而蚯蚓蠕动离开时会去哪里呢？
That's right,underground.
说对了,地下
Earthworms spend most of their time safe in underground tunnels called burrows.
蚯蚓大多数时间在叫做地洞的地下洞穴中安全地度过，
It not only keeps them hidden from predators, but that nice, wet soil keeps their skin moist.
这不仅是为了藏起来远离捕食者，并且美妙湿润的泥土能让它们的皮肤保持湿润。
And that's super important.
那才是最重要的。
Because earthworms need to breathe just like people do, but they don't do it in the same way.
因为蚯蚓像人一样需要呼吸，但它们的呼吸方式与我们不同。
They actually absorb oxygen through their skin.
实际上，它们通过皮肤吸入氧气
And in order to do that, they need to keep wet.
为此，它们需要保持湿润。
That's why you're most likely to see earthworms when you're digging through damp soil or mud!
这就是为什么你最有可能在挖湿润的泥土或淤泥时见到蚯蚓。
But maybe you've seen earthworms even when you haven't been making mud pies.
甚至在你做泥团前，你也可能见到蚯蚓。
Have you ever seen them hanging around on the sidewalk after a rainstorm?
你见过它们雷阵雨后在人行道上闲逛吗？
A rainy day for an earthworm is a perfect moving day.
雨天是蚯蚓搬家的好时候。
Sometimes one area becomes too crowded with earthworms, so they need to find a new home.
有时候一个地方的蚯蚓太多了，所以它们需要搬个新家。
But they need to keep their skin moist while they're out moving around.
但当它们外出时也要保持皮肤湿润。
So earthworms use those soggy days to come out and look for a new place to live.
所以蚯蚓趁着这些闷湿的日子外出，寻找一个新住所。
Then back into the ground they go!
然后回到它们住的地下。
But the dirt isn't just a safe place for worms to hide, it's also their food.
但是土地不仅是蚯蚓躲藏的安全场所，也是它们的食物。
As an earthworm moves through the soil, it's also is eating the dirt!
一条蚯蚓在土地里蠕动时，它也在吃土。
Earthworms get their nutrients from dead and decaying parts of plants, like leaves and roots, that are in the soil.
蚯蚓从死亡腐烂的植物器官中获取营养，如泥土里的叶子和根。
And earthworms are hungry. They can eat half their bodyweight in just one day!
而且蚯蚓很饥饿，它们一天就能吃掉它们一半体重的食物。
But maybe the coolest thing about earthworms?
但是蚯蚓最厉害的是什么呢？
As they munch through the soil, they actually make the soil better for the rest of us.
它们咀嚼泥土时，实际上是让土地变得更肥沃。
How do they do that?
它们是怎么做到的呢？
Well, the tiny tunnels that earthworms make as they wiggle through the dirt help bring water and air deep into the ground.
当它们在泥土里的小通道蠕动时，能带进来水和空气。
And that makes it easier for other living things—like plants and fungus—to live in it.
那让其他生物如植物和真菌在里面的生存变得容易些。
Plus, as earthworms break down all of those dead plant parts,
而且，蚯蚓分解了植物的所有死亡部分，
they help spread around all of the nutrients that are in them, to make food for new things to grow.
它们把其中的所有营养散播开来，为新生物生长提供食物。
Some people even keep earthworms in their garden on purpose!
一些人甚至特地将蚯蚓放在它们的花园里 ，
They feed the earthworms things like banana peels and apple cores.
它们用香蕉皮和苹果核之类的东西喂养蚯蚓。
Then, the worms turn those scraps into composta rich, smelly, nutritious kind of plant food made from … dead plants!
然后蚯蚓将这些废弃物变成肥料，用死去的植物做成丰富发臭的某种植物营养。
To you, it might just look like trash, but to an earthworm? It's treasure!
对你来说，它可能看起来像垃圾，但对一只蚯蚓来说，它是财富。
Healthy earthworms means healthy soil! And healthy soil means healthy people,
健康的蚯蚓意味着健康的土壤，而健康的土壤意味着健康的人类。
because we need it to grow plants for our own food!
因为我们需要它培养植物，为我们提供食物。
So the next time you come across an earthworm, thank them!
所以下一次你遇到蚯蚓，得感谢它们。
They're hard at work helping flowers, trees, grass, and plants grow.
它们在努力地帮助花朵、大树、小草和植物生长。
And thanks to you for joining us here at SciShow Kids!
感谢您观看我们本期的儿童科学秀。
If there's anything that you'd like to learn more about, ask your parents to help you email us at kids@thescishow.com,
如果你想了解更多的事情，请你的父母帮忙给我们发邮件，地址是kids@thescishow.com。
And we'll see you next time!
下次再见！
