霸王龙也许统治了白垩纪，但异特龙才是侏罗纪的王者。

While any environment that we have on earth today we have a top predator, Allosaurus was the top predator of the late Jurassic in western North America.

在地球上的任何环境里都有一种顶级掠食者，异特龙是侏罗纪晚期北美西部的顶级掠食者。

Here in Alaska, you've got the brown bear, up in Arctic Alaska, polar bear, Africa, Serengeti, the lion, and if you're in India, the tiger.

在阿拉斯加，是棕熊，在阿拉斯加的极地区，是北极熊，非洲的塞伦盖提，是狮子，要是在印度，就是老虎。

And in western North America, it was Allosaurus.

在北美西部，那时候就是异特龙。

It had powerful jaws with pretty sharp teeth.

它的双颚有力，牙齿非常锋利。

It had extremely large claws on its hand which were very useful for gripping and tearing.

它前肢的爪子非常大，对抓住和撕扯猎物是很有用的。

For nearly 20 million years, Ceratosaurus had dominated the region of North America where the Rocky Mountain states are now.

近两千万年里，角鼻龙统治着北美地区就是现在的落基山区。

But the emergence of Allosaurus, a bigger, faster, stronger adversary, changed everything.

但是更大、更快、更壮的对手异特龙的出现，改变了一切。

What made Allosaurus unique was its build.

让异特龙出类拔萃的是它的体型。

It was much more powerful than other predators of the late Jurassic era, including Ceratosaurus which it dwarfed.

它要比侏罗纪晚期其它的掠食者强大得多，也包括与它相形见绌的角鼻龙。

Allosaurus was one of the largest predatory dinosaurs in North America at the end of Jurassic.

异特龙是侏罗纪晚期北美地区最大的掠食恐龙之一。

He ultimately displaced Ceratosaurus as being the apex predator.

它最终取代了角鼻龙成为了顶级掠食者。

You were face to face with Allosaurus.

你要是面对面地碰到异特龙。

First of all, you'd be in big trouble.

首先，你麻烦大了。

Guess the first thing, you'd turn around and run.

猜首先你会转身就跑。

By the time you did, he would have foot planted on you, planting you face first into the mud, and would reach down, grab on, brace himself, and basically chop you in half.

你跑掉时候，它会一脚把你踩住，让你脸朝下摔进泥里，然后弯腰，咬住你，撑住自己，而且基本上会把你撕成两半。

For the bite force, probably comparable to a great white shark.

它的咬合力，应该可以媲美大白鲨。

Allosaurus had considerable improvements on the Ceratosaurus.

异特龙要比角鼻龙进步很多。

Its size was unprecedented for its time.

它的体型就前所未有。

Measuring about 10 meters long, 4 and a half meters tall and weighing up to 5 tons.

有大概十米长，四米半高，重可达五吨。

Allosaurus was the size of a railway carriage.

异特龙的大小相当于一节火车车厢。

When the first big skeletons of Allosaurus were uncovered, people finally saw that there were meat eating dinosaurs that was as big as killing whale with powerful claws on its hand.

当第一具异特龙的巨大骨架被发现时，人们终于看到了这种食肉恐龙，跟虎鲸一样巨大前爪非常发达。

Truly, a terror from the Jurassic period.

这可真是侏罗纪时期的凶神恶煞。

One social characteristic made Allosaurus even more dangerous.

异特龙的一个社会属性使之更为危险。

Ongoing research suggests they lived in packs.

持续的研究表明它们群居生活。