国家地理 终极者—鲨鱼（在线收听）

What exactly is the power that drives nature's most famous jaws? In New Zealand, this great white shark drowned in a fisherman's net.

到底是什么力量驱使着自然中最著名的大白鲨？在新西兰，这只大白鲨在渔民的网中溺亡。

And scientists Kara Yopak and Clinton Duffy are preparing an ultra-rare great white shark dissection.

科学家卡拉·约帕克和克林顿·达菲准备对一种非常稀有的大白鲨进行解剖。

"Ah, I've never dissected one that is the size before."

“之前我从没有解剖过这种大白鲨。”

It's a unique opportunity to study a great white's near-perfect design, including its fearsome jaws.

这是一次研究大白鲨近乎完美设计的机会，包括它可怕的颚片。

"The jaws of great white are really, really valuable. So most of the time, if we do get a specimen to measure, it looks a little bit more like this.

“大白鲨的颚片非常非常宝贵。所以多数时候，如果我们有测量的样本，和这个差别很大。

Not nearly as pretty. That fishermen know pretty much. We're catching animal of, yes, for, um, a fishing competition or even just in its net.

并非像真品一样完美。渔民知道的很多。我们在钓鱼比赛中或者甚至是在渔民的网中捕获动物。

Um, we'll remove the jaws and quite often its fins as well. The jaws are amazingly valuable.

我们移除了颚片以及鳍片。颚片价值极高。

Uh, they can go anywhere, from ten to twenty thousand dollars. Um, you can see them, I mean, being sold on eBay.

它们可流通到任何地方，价格在一到两万美元之间，你可以在易趣上售卖。

It's kind of such a status symbol. Everybody knows the great white shark. When you have an idea of shark in your head, it's gonna be this one."

这像是一种社会地位象征。每个人都知道大白鲨。当你有想过大白鲨的样子，就是这样了。”

The jaws of a great white are evolutionary marvel.

大白鲨的颚片是进化的奇迹。

They actually burst forward, allowing for a bite that shears up to 30 pounds of flesh in a single mouthful.

它们突然前进，一口可以要掉30磅的肉。

About 50 teeth lie in the front of a great white's jaws. The lower teeth act like daggers, stabbing and holding prey in place.

大白鲨颚片前端有约50颗牙齿。下颌牙充当匕首，刺穿并咬住猎物。

The larger upper teeth are like steak knives, slicing off giant mouthfuls of a victim.

上颌牙较大，像是牛扒刀一样，切割猎物。

And behind this front row of teeth are literally hundreds of others, ready to be pressed into service.

在牙齿前排后是百颗其他牙齿，随时准备紧急服务。

But to truly understand this extreme design, you have to go beneath the skin.

但是要真正理解这种极端的设计，需要深入皮肤下方。

Unlike human beings, the great white's jaws aren't fused to the skull.

和人类不同，大白鲨的颚片并没有和脑壳相连。

They hang loosely underneath the braincase, ready to execute their signature bite.

它们悬挂在脑壳下方，随时准备执行标志性的一击。

First, the snout rises and opens the mouth. At the same time, the lower jaw pushes down, widening the gape.

首先，鼻子抬起，张开嘴。同时，下颚向下推，扩大张开。

Next, special muscles in grooves in the skull push the upper jaw forward, exposing gums and teeth.

接下来，脑壳中凹槽的特殊肌肉推动上颌前进，暴露出牙龈和牙齿。

The lower jaw rises, latching onto the prey, and the snout slams down, hammering the upper jaw with almost 700 pounds of force.

下颌抬起，紧抓住猎物，鼻子猛地落下，用700磅的力量敲打上颌。

These extraordinary teeth are clearly designed to kill, but they may also serve another purpose: delivering a message to other great whites.

这些非凡的牙齿设计就是为了杀戮，但是或许也有其他用途：向其他大白鲨传递信息。

"She actually has some scarring out here. You can see where this scar's coming down, turn around underneath the eye.

“她这里真的很有多疤痕。你可以看到这条疤痕从这里下来，划到眼睛下方。

The ones on the side of a pectoral fin, they appear to be shark bites. This one is likely to be a tooth mark, possibly another shark.

这些在胸鳍的一侧，这些是鲨鱼的咬痕。这一个像是牙痕，很可能是另一条鲨鱼的牙痕。

These guys are not necessarily one big happy family when they get together."

这些家伙在一起时，并不是一个快乐的家庭。”

Great whites can be covered in battle scars. It's believed they bite one another to assert dominance, compete for a meal and even to mate.

大白鲨的身上会有战殇。人们认为它们会为了领地、食物和交配权而相互撕咬。

"How these guys get together, of course, and don't kill each other is an, it's a really interesting question."

“当然，这些家伙如何在相处时不咬死对方，这是个有趣的问题。”