Dugongs are the largest herbivores in the sea.

儒艮是海洋里最大草动物。

Thorns help protect the plant from plant-eating animals.

刺有助于保护植物免受草动物伤害。

It also suggests that herbivory evolved in the crocodile clan on several occasions.

该研究还表明鳄鱼家族草性进化了好几次。

For example, young shore crabs that use camouflage to hide from predators.

比如用伪装来躲避捕者年轻草蟹。

So back the time, there were millions of big herbivores roaming the landscape.

过去，有数百万大型草动物在这片土地上漫游。

The pronghorn lived alongside other grazers still around today, including bison.

叉角羚曾经与像今日仍存活野牛那样其他草动物共伴而生。

Herbivores, for example, leave a third of food nutrients in their poop.

例如，草动物大便中含有三分之物营养。

All these Cretaceous plant eaters, with their complicated apparatus, they're all much more sophisticated.

所有这些白垩纪草动物都有其复杂防御器官，它们都是很高级生物。

For the herbivore Sauroposeidon, death by Deinonychus is violent and painful.

对于草性波塞东龙，被恐爪龙杀死将是残暴而痛苦。

Prehistoric plant eaters live every day with a target on their back.

史前世界草动物每天都生活在弱肉强环境中。

But why are these trees so well armed against browsing animals like these giraffes?

为什么这些树会如此武装自己，以防御象长颈鹿这样草动物呢？

Many species within these genera grow on dung from large herbivores.

这些类属中许多物种都是靠大型草动物粪便生长。

At first, the group thought the bone belonged to a smaller plant-eating dinosaur.

起初，研究小组认为这块骨头属于种较小草恐龙。

The East African savannahs support millions of grazers.

东非大草原养育着成千上万草动物。

Carnivores tend to have simple teeth. Omnivores have more complex teeth. Herbivores have the most complex teeth of all.

肉动物牙齿比较简单。杂动物牙齿更复杂。草动物牙齿是所有牙齿中最复杂。

Princeton University researchers analyzed 65 years of data about more than 250 populations of large herbivores.

普林斯顿大学研究人员分析了65年来有关250多个大型草动物种群数据。

On the great flatlands, among the thousands of animals that graze here, the clan is excited.

在这个大平原上，在成千上万草动物之间，这个家族兴奋不已。

On just about every measure, they found plant eaters were most at risk, especially in forest environments.

他们几乎从所有方面都发现草动物灭绝风险最大，尤其是森林环境中草动物。

Grazing animals, including horses, were nearly wiped out in the Hemphillian event about five million years ago.

发生在大约500万年以前亨菲利世事件中，包括马在内草动物差点儿被扫而光。

They managed to survive the drought, eventually expanding in number to replace the horse as dominant grazer.

他们从干旱存活了下来，并最终在数量上超过了马，成为了最大草群体。