Though the Cretaceous asteroid cleared the stage, mammals did not really get going until 10m years later, in the Eocene epoch.

尽管白垩纪时期的小行星灭绝了居统治地位的恐龙，但哺乳动物却一直到1000万年后的始才真正兴起繁盛起来。

Eocene, so, by about 40 million years ago, many of them had gone extinct.

，因此，到大约 4000 万年前， 其中许多已灭绝。

By the late Eocene, practically all of the primates on those continents died out.

到始期， 这些大陆上几乎所有的灵长类动物都灭绝了。

Floristic Region, but their family was clearly much more widespread during the Eocene Epoch.

植物区的地区发现，但它们的科显然 要远得多 在始时期广泛存在。

Other residents of Eocene Antarctica probably came from South America as well.

始南极洲的其他居民可能 也来自南美洲。

In the United States, Boverisuchus shows up fully-formed and ready to run in the early Eocene.

在美国，始早期，Boverisuchus 已成形并准备好奔跑。

Around 34 million years ago, the Eocene-Oligocene Transition  marked the first major period of global cooling and glaciation.

大约 3400 万年前，始-渐过渡标志着球变冷和冰川作用的第一个主要时期。

Over the course of the Eocene epoch, the climate slowly began to cool.

在始时期，气候 开始慢慢变冷。

Clearly, Antarctica’s biodiversity took a hit after the Eocene.

显然，南极洲的生物多样性 在始之后受到了打击。

The Paleocene-Eocene Thermal Maximum, 55 million years ago, was so warm, crocodiles swam the waters of the Arctic Circle.

5500 万年前的古-始极热期非常温暖，以至于鳄鱼在北极圈的水域中游来游去。

What we do know is that the late Eocene and early Oligocene was a time of global cooling.

我们所知道的是，始期和 渐早期是球降温的时期。

As a result, our world is warming faster than it did back in the Eocene.

结果，我们的界变暖的速度 比始早。

So given its size, it was able to support many different ecosystems in the Eocene.

所以考虑到它的大小，它能够支持 始许多不同的生态系统。

But what happened to these Eocene animals?

但是这些始动物发生了什么？

So by the time the Eocene Epoch was over, North America no longer had the right habitat for primates.

因此， 当始结束时，北美不再有适合灵长类动物的栖息地。

This period  of warming, known as the Paleocene-Eocene Thermal Maximum or PETM, was likely caused by  a combination of natural factors.

这一变暖时期被称为古-始极热事件或PETM，可能是由多种自然因素造成的。

And they arrived in South America by the middle Eocene Epoch, around 42 million years ago.

他们在大约 4200 万年前的始中期到达南美洲。

And a big environmental change was also underway in the last half of the Eocene, thanks to the chemistry of mountain-building.

由于造山的化学作用，始后半期也发生了巨大的环境变化。

You see the Amazon formed during the Eocene epoch, up to 56 million years ago when the whole world was a lot warmer and wetter.

你可以看到亚马逊河形成于始时期，距今约5600万年前，当时的地球要温暖得多，湿润得多。

Or there's the Eocene, more than 34 million years ago, a hothouse time during which the continents drifted into their present configuration.

或者是超过 3400 万年前的始，这是一个温室时代，在此期间大陆逐渐变成了现在的形态。