As the climate heated up, the forests receded, and humans ventured out into the savanna.

随着气候，林退化，人类铤而走险，进入草原。

The open savanna beneath the trees makes it easy to move around and feed.

树下开阔草原使得它可以轻松走动和觅食。

In other words, evidence suggesting African savanna elephants give each other names.

换句话说，这表明非洲草原大象会给互相起名字。

Until now, thanks to some wild savanna sparrows.

多亏了某些野生稀树草鹀，现我们能用野鸟做实验了。

So, they have to be careful when cruising the African savanna.

因此，它们非洲大草原巡游时必须小心。

A hundred thousand years ago, we were all in the African savanna.

十万年前我们都非洲大草原。

In fact, it transforms from desert to lush savanna about every 21,000 years.

事实上，那里大概每隔21000年就会从沙漠成苍翠稀树大草原。

It sort of resembled a savanna but without grass.

这就像是一个没有草大草原。

Take the savanna, for example — a transitional biome between forests and grasslands.

以稀树草原为例，它是林和草原之间过渡生物群落。

They walk twice as far as lions living on the savannas of East Africa.

它们行经路程是生活东非大草原上狮子两倍。

But the thorny acacia are more numerous on the open savanna, where they need to defend themselves.

而有刺金合欢树更多地长开阔草原中，那，它们需要保护自己。

For instance, all of the plants and animals on the savanna make up the savanna community.

例如，草原系统所有动植物构成了草原一个群落。

It's 17,000 feet high, which makes its summit some 30 degrees colder than the surrounding savanna.

海拔超过五千米峰顶，温度比周围草原低三十度左右。

One key reason is that our ancestors on the savannas of Africa were really good at one thing.

一个关键原因于我们非洲大草原上祖先真非常擅长一件事情。

To get away from some lion that wanted us for Sunday brunch on the savannas of East Africa.

远离一些想东非大草原把我们当做周日早午餐吃掉狮子。

Scientists can easily count the number of savanna elephants from an airplane because there are very few trees.

科学家们可以很容易地借助飞机数出稀树草原大象数量，因为那里树木非常少。

America during the last Ice Age, it was probably a savanna, with its own set of native earthworms.

当地可能就是莽原，还有原生种蚯蚓。

Then, all of the savanna's carnivores eat animals that have gotten energy from plants somewhere along the line.

然后，草原上所有食肉动物都以从植物中获取能量动物为食。

We need to cross this area of water to get to the savanna and find our locust swarms.

我们要穿过这片区域，才能到达草原找到我们蝗群。

The fires burned in parts of both the large Cerrado savanna and the world's largest tropical wetland, the Pantanal.

大火烧毁了塞拉多大草原和世界上最大湿地潘塔纳尔部分地区。