When aggravated by a predator, they, you know, puff up.

當受到捕食者的激怒時，它們，你知道，會膨脹。

Some puffers, like the porcupine fish, become a bona fide spike ball, moving through the water seemingly out of control.

有些河豚，像豪豬魚，成為一個真正的刺球，似乎在水中失控地移動。

But if you peer inside a puffer, you'll learn that puffing up isn't the only trait that makes these fish one of the most threatening creatures in the sea.

但是，如果你凝視著一條河豚，你會發現膨脹並不是使這些魚成為海洋中最具威脅性的生物之一的唯一特點。

Contrary to what it looks like, puffer fish are not like balloons.

與外表相反，河豚並不像氣球。

Because what's normally inside them isn't air; it's water.

因為它們正常內部的東西不是空氣，而是水。

What they do is they actually take water into their mouths in a big mouthful of water, and then they pump it down into their stomach.

這是伊莉莎白·布雷納德，布朗大學的一位生物學家和河豚專家。

That's Elizabeth Brainerd, a biologist and puffer fish expert at Brown University.

它們實際上是將水吸入嘴中，一大口水，然後將其吸入胃中。

And they do that anywhere 10 or 15 times; pump, pump, pump, pump, pump, pump, until they inflate completely,

這樣做10到15次，吸，吸，吸，吸，吸，吸，直到完全膨脹，

and then they hold it and they'll just be a big, spiny ball.

然後它們會保持這種狀態，變成一個又大又多刺的球體。

And as you might expect, this requires some pretty sophisticated biology, starting with the stomach.

正如你可能期望的，這需要一些相當複雜的生物學，從胃開始。

It's made of dozens of tiny folds, kind of like an accordion.

它由數十個小褶皺組成，有點像手風琴。

These folds are important because when the stomach fills up with water, it can expand without rupturing.

這些褶皺很重要，因為當胃充滿水時，它可以擴展而不破裂。

And puffer fish expand a lot; up to three times their size.

而河豚可以膨脹相當大，高達它們正常大小的三倍。

That's like if an average human man could inflate his waist to a circumference of 3 meters.

這就像如果一個普通的人可以將他的腰部膨脹到3米的圓周。

But there is a drawback to these amazing skills.

但是這些令人驚奇的技能也有一個缺點。

Brainerd suspects that puffer fish stomachs have actually lost the ability to digest food, which means their intestines have to do all the work.

布雷納德懷疑河豚的胃可能實際上已經失去了消化食物的能力，這意味著它們的腸道必須完成所有的工作。

You know, given the apparent importance of this defense mechanism, they've given up the advantages of having a stomach where some digestion can start.

你知道，鑑於這種防禦機制的明顯重要性，它們放棄了擁有一個可以開始一些消化的胃的優勢。

But the stomach?

但是胃？

It's just one of many bizarre features inside a puffer.

那只是河豚體內眾多奇異特徵之一。

For example, they have specialized muscles that you won't find in most other fish.

例如，它們擁有專門的肌肉，在大多數其他魚類中是找不到的。

Some in their mouth, which pump all that water into their stomach;

有些在它們的嘴裡，將所有的水吸入它們的胃；

some in their esophagus, to seal off their stomach like a drain plug once it's full;

有些在它們的食道，像排水塞一樣密封它們的胃一旦滿了；

and some in the base of their bellies, which contract to squeeze out water when they're ready to deflate.

還有一些在它們腹部的基部，當它們準備放氣時，這些肌肉會收縮，擠出水來。

But what you won't find inside is even more bizarre.

但你在裡面找不到的更是更加奇異。

There are a couple characters that are really helpful in their ability to puff up,

有一些特點在它們膨脹的能力方面真的很有幫助，

and one of those is that they don't have any ribs, and another one is they don't have any pelvis.

其中之一是它們沒有任何肋骨，另一個是它們沒有任何骨盆。

In other words, puffers are essentially missing bones.

換句話說，河豚基本上缺少骨頭。

And that's a good thing, because otherwise they'd get in the way of inflation.

這是一件好事，因為否則它們會妨礙膨脹。

In fact, according to Brainerd, if it weren't for these missing bones, puffer fish would probably have never evolved this way in the first place.

事實上，根據布雷納德的說法，如果不是這些缺失的骨頭，河豚可能根本不會以這種方式進化。

And that would be a shame, since puffing up really is a good defense.

這將是一種損失，因為膨脹確實是一種很好的防禦機制。

Consider one old study in which researchers watched birds go fishing.

有一項舊研究，研究人員觀察了鳥類捕魚的情況。

The birds caught 11 puffer fish, but they dropped nearly half of them because the fish started to inflate.

鳥類捕到了11條河豚，但由於這些魚開始膨脹，它們將近一半的魚丟掉了。

But what's more surprising is that the birds left with empty beaks might have been the lucky ones.

但更令人驚訝的是，無功而返的鳥可能是幸運的。

Because puffers have another, more potent defense up their sleeves.

因為河豚還有另一種更強大的防禦手段。

Their bodies are laced with a neurotoxin called tetrodotoxin.

它們的身體充滿了一種叫做河豚毒素的神經毒素。

It's up to 1,200 times more poisonous than cyanide.

它的毒性高達氰化物的1200倍。

So poisonous that one puffer fish can kill 30 adult humans.

毒性如此之高，以至於一條河豚可以殺死30個成年人。

So poisonous that puffers are reportedly the second most poisonous vertebrate in the world, which is why it's also surprising that us, humans, we actually eat them. That's right.

毒性如此之高，河豚據說是世界上第二毒的脊椎動物，這就是為什麼令人驚訝的是我們人類實際上還吃它們。沒錯。

In Japan, puffer fish is actually a delicacy called fugu, which only trained chefs can prepare.

在日本，河豚實際上是一種叫做 fugu 的佳餚，只有受過培訓的廚師才能準烹飪。

And considering that these fish are basically spike balls filled with poison and we're still serving them in restaurants, they must be seriously delicious.

考慮到這些魚基本上是充滿毒素的刺球，我們仍然在餐廳中供應它們，它們肯定非常美味。