Stalking the Cretaceous are predators like Tyrannosaurus Rex, with jaws that can bite down with nearly four tons of force.
在白垩纪潜伏着雷克斯霸王龙这样的捕食者，它们的血盆大口有四吨的咬力。
And Deinonychus, sporting claws that could slice right through flesh.
而恐爪龙它们的爪子可以割穿血肉。
But the prey these carnivores hunt are heavily armed.
然而这些食肉动物的猎物也是全副武装。
Often in reconstructions of dinosaurs, we just see the meat eaters attacking the herbivores,
在对恐龙化石的重塑过程中，我们总想着食肉动物会攻击食草动物，
and it's easy to miss the fact that, in the real world, herbivores fight back.
很容易忽视一个事实，就是在现实世界里食草动物是会还击的。
The plant eater Sauroposeidon defends itself by growing to mammoth proportions.
以植物为食的波塞东龙通过迅速长大进行防御。
This one is a juvenile. But it's almost 6 meters tall, an animal on the edge of adolescence and an animal on the run.
这只恐龙尚未成年。但已将近6米高了，它即将度过青春期，它正在逃跑中。
It's being chased by two raptors...these raptors are known as Deinonychus.
它被两只猛禽类追赶着这两只猛禽正是恐爪龙。
These tiny killers work as a team.
这些瘦小的杀手结队作战。
Deinonychus wouldn't weigh much more than a human being.
恐爪龙不比人重多少。
And when they're attacking things like Sauroposeidon,
当它们攻击像波塞东龙这样的猎物时，
it would be a big advantage for them to be able to act as a group.
团队作战对它们来说是个巨大的优势。
They're actually increasing their chance of getting a meal. It's a strategy still used today.
事实上，它们增加了自己获得食物的机会。这种策略一直沿用至今。
Working together, lions will take on prey as big as a four-ton elephant, and they only have teeth and claws.
携手合作的狮群能捕食重达四吨的大象，而它们只有牙齿和利爪。
Deinonychus employs an array of weaponry more powerful than any creature today.
恐爪龙拥有的武器比今天任何生物的都要强大。
Sauroposeidon's only defense is its massive size,
波塞东龙只靠它那庞大的身躯防御，
but Deinonychus have learned that nearly any defense can be breached with the right armaments...
但恐爪龙却知道，只要使用正确的武器，任何形式的防御都能被击破。
Like recurved hand claws almost 8 centimeters long,
比如近8厘米长的内弯手爪形似登山者的鞋钉，
designed to grip into the bodies of prey like a mountain climber's spikes.
专门用于刺进猎物的身体。
The ideal attack is to jump up, grab ahold of the prey, position the prey, and then strike.
理想的攻击就是跳到猎物身体上，抓紧猎物贴住不放，然后开始出击。
So the arms are to position your body to deliver that killing blow.
所以胳膊是用来稳住身体以便送出必杀一击。
It could strike very quickly, and it could, if it was attacking a larger animal,
它出击速度非常快，如果攻击更大的动物，
use those arms to pull itself up against it.
它可以靠胳膊爬到猎物背上。
By doing so, it could bring its other main weapon into attack, and that's its foot claws.
这样，可以让其它主力武器投入战斗，也就是脚爪。
