Life recovers, and then we're in the Devonian period after that.

生命恢复了，然后们进入泥盆纪。

The long-ago seas of the Carboniferous and Devonian swarmed with tiny plankton that wrapped themselves inside tiny protective shells.

泥盆纪和石炭纪的古代海洋里生活着大批微小的浮游生物。它们躲小小的保护性壳里。

The Ordovician (440 million years ago) and Devonian (365 million) each wiped out about 80 to 85 percent of species.

奥陶纪（44000万年以）和泥盆纪（36500万年以）消灭了大约80%——85%的物种。

The clue to this ancestor, it was assumed, would be found in the Devonian era, from about 400 million years ago.

据认为，这个祖先的线索要大约4亿年以的泥盆纪寻找。

Going back even further, we find the Late Devonian extinction about 360 million years ago.

再往追溯， 们发现大约 3. 6 亿年的晚泥盆世大灭绝。

While fish with jaws first appeared in the Silurian, they proliferated in the Devonian.

虽然有颚的鱼最早出现 志留纪，但它们泥盆纪大量繁殖。

Well, during the Devonian, things were … complicated.

，泥盆纪期间，事情… … 很复杂。

But these creatures lived in a very different world from the Devonian.

但这些生物生活 与泥盆纪截然不同的世界中。

The venerable family of Roach has been crawling around since at least the devonian.

至少从泥盆纪开始，可敬的 Roach 家族就一直四处爬行。

By the end of the Devonian, all of the giant marine eurypterines had gone extinct.

到泥盆纪末期，所有的巨型海洋海蝎都已经灭绝。

But in the Devonian, a new branch of the cephalopod family tree appeared: ammonites.

但泥盆纪，出现了头足类 家族树的一个新支：菊石。

The culprit was an apex predator that dominated the seas of the late Silurian and early Devonian: the sea scorpion.

罪魁祸首是一种顶级捕食者，它统治了晚志留世和早泥盆世的海洋：海蝎。

Once plant life started to spread and diversify on land in the Devonian Period, fungi were there to help again.

一旦植物生命泥盆纪开始陆地上扩散和多样化，真菌又来帮忙了。

That's because a new evolutionary pressure was waiting for cephalopods in the Devonian Period: fast, jawed fish.

那是因为泥盆纪时期，头足类动物面临着一种新的进化压力：快速且有颌的鱼类。

Oxygen levels in the Devonian and Carboniferous periods, when terrestrial life first bloomed, were as high as 35 percent (as opposed to nearer 20 percent now).

陆地生命大幅度增加的泥盆纪和石炭纪，空气中的氧的浓度高达35%（现是将近20%）。

And the evolution of armor may seem like an obvious adaptation for protection, especially in the Devonian's crowded seas.

而装甲的进化可能看起来像是一个显而易见的保护适应性特征，尤其是拥挤的泥盆纪海域。

But by the end of the Devonian, 60  million years later, giant trees, like Archaeopteris, had spread around  the world - and changed it, forever.

但到了 6000 万年后的泥盆纪末期，像始祖蕨这样的巨树已经遍布世界各地， 并永远地改变了世界。

But as the Silurian gave way to the Devonian, a dangerous new competitive pressure entered the seas — the armored, jawed fish known as the placoderms.

但当志留纪过渡到泥盆纪时，一种新的危险竞争压力进入了海洋——那就是被称为盾皮鱼的装甲有颌鱼。

Fish began their transition onto land 400 million years ago, during in the Devonian period.

鱼类4亿年的泥盆纪开始了向陆地的过渡。

In the Late Devonian, giant armored jawed fish -- the placoderms -- would come to dominate these seas and force other ocean-dwellers to adapt, flee, or perish.

晚泥盆世，巨大的装甲有颌鱼——盾皮鱼——开始统治这些海域，迫使其他海洋生物适应、逃离或灭绝。