When Witmer studied the skull, he saw that there were serrated ridges in the teeth.
维特莫研究其颅骨时，看到牙齿里有锯齿状的脊状隆起。
The ridges are remarkably similar to those of another animal with a deadly bite, a Komodo dragon.
这些隆起跟另一种撕咬致命的动物非常相似——科莫多龙。
Another interesting attribute about the teeth of Tyrannosaurus Rex, is that the serrations on the teeth,
霸王龙的牙齿另一个有趣的特点是，牙齿上的锯齿状凸起，
the fine little ridges, perhaps actually lodged little bits of flesh from a previous meal and that rotting of that flesh would've produced a great deal of bacteria.
细小的隆起里面可能会留下上一顿美餐的肉屑，这些肉腐烂后会产生大量细菌。
What we're talking about here is really bad oral hygiene.
我们说的可真是很糟糕的口腔卫生。
Now, in today we actually have animals, the Komodo dragon, this large gigantic lizard, that actually has what we call a septic bite.
如今我们确实有这样的动物，比如科莫多龙这样的巨大蜥蜴，这种攻击被我们称为败血一咬。
That, actually, when it bites an animal, it, in a sense, infects it with the bacteria in its mouth.
其实就是当它撕咬别的动物时把口腔里的细菌感染给该动物。

Equipped with these features it seems unlikely that any creature would attack a Tyrannosaurus Rex, even a juvenile.
有了这些特点的武装，看来好像没有什么动物会攻击雷克斯暴龙，哪怕是尚未成年的。
So to determine who would attack this T-Rex, paleontologists had to get a complete picture of how T-Rex lived, and fought.
要确定这头霸王龙遭到谁的攻击，古生物学家必须要获得霸王龙生活和战斗的全景。
The first step was to study its environment.
第一步是研究其生活环境。
When we look at the Cretaceous environments of this part of the world, it's not all that different than environments that we still have today.
我们在了解白垩纪时期世界的这部分环境时，发现跟现在我们有的没那么大区别。
When we look at the plants, when we look at the climate and so on,
我们研究了植物，也关注了气候等，
we could assume that we were looking at something that looks very similar to what we see in the Gulf States, climate wise and everything else-wise.
能够推测我们要面对的环境跟现在墨西哥湾各州非常接近，无论是气候还是其它方面。
Fossilized plants found near the skeleton revealed that the young T-Rex lived in an area near conifer, pine and magnolia trees.
在骨骸附近发现的化石植物揭示，年幼的霸王龙生活的地区附近有针叶林松树和木兰树。
They also discovered prehistoric ash, which suggests that volcanic activity occurred on a regular basis.
人们还发现了史前火山灰，表明那时的火山活动频繁发生。
But in the investigation, scientists discovered something else.
不过在调查中，科学家们还发现了别的信息。
Bones of prehistoric crocodiles and fish were found nearby.
附近还有史前鳄鱼和鱼类的骨骸。
This suggests that the T-Rex's body had been washed into a river during flooding.
这说明霸王龙的尸体被洪水冲入了一条河流。
Evidence of a violent earth that could change without warning.
这是狂暴地球突发剧变的证据。
After studying its environment, the investigation looked to the behaviour of Tyrannosaurus Rex.
在研究了环境之后，调查还要关注雷克斯暴龙的行为。
Using evidence found in the bones and study from modern animal behaviour,
通过在骨骸上找到的证据和对现代动物行为的研究，
scientists piece together how these huge dinosaurs hunted, fought and raised their young.
科学家们推断出了这种庞大恐龙是怎样狩猎、战斗和抚育后代的。
Tyrannosaurus Rex was the ultimate aggressor.
雷克斯暴龙是终极攻击者。
There's nothing that Tyrannosaurus Rex was afraid of including its biggest prey item, Triceratops,
雷克斯暴龙无所畏惧，包括它们最大的猎物——三角龙，
which had these big formidable horns and frill to protect its neck.
三角龙有可怕的大角和保护颈部的褶皱。
But there were no other dinosaurs around that would even give Tyrannosaurus Rex a second thought about its own safety.
不过周围没有别的恐龙会让雷克斯暴龙对自身安全有所顾虑。