Humans weren't at risk of dying out during the PETM, because we didn't exist.

在古–始极热事件时人类并没有濒临灭绝危险，因为我们还不存在。

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。

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

结果，我们界变暖速度 比始早。

But what happened to these Eocene animals?

但是这些始发生了什么？

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

始南极洲其他居民可能 也来自南美洲。

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

显然，南极洲生多样性 在始之后受了打击。

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

始晚期， 这些大陆上几乎所有灵长类都灭绝了。

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

所以考虑大小，能够支持 始许多不同生态系统。

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

植区地区发现，但们科显然 要远得多 在始时期广泛存在。

But about 49 million years ago, in the mid-Eocene, the climate began to get cooler and drier.

但大约 4900 万年前，在始中期，气候开始变得更凉爽和干燥。

In the early Eocene Epoch, probably before mustelids appeared, our planet had a warm climate.

在始早期，可能在鼬科出现之前，我们星球气候温暖。

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

尽管白垩纪时期小行星灭绝了居统治地位恐龙，但哺乳却一直1000万年后始才真正兴起繁盛起来。

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

我们所知道是，始晚期和 渐早期是全球降温时期。

Let's rewind back to the Eocene, about 45 million years ago.

让我们回大约 4500 万年前始。

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

5500 万年前古-始极热期非常温暖，以至于鳄鱼在北极圈水域中游来游去。

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-渐过渡标志着全球变冷和冰川作用第一个主要时期。

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

他们在大约 4200 万年前始中期达南美洲。

For example, Juxia from the Late Eocene epoch of China was about the size of a horse.

例如，中国始晚期巨霞大约有马那么大。

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 万年前始，这是一个温室时代，在此期间大陆逐渐变成了现在形态。

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.

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