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

虽然有颚鱼最早出现在 志留纪，但它们在泥盆纪大量繁殖。

We were passing through rocks of the transition or silurian [l] system.

我们正在穿过过渡或志留纪[l]系统岩石。

One of the ideas is scorpions came out of the water from Silurian period long time ago.

——其中一个想法是蝎子很久以前从志留纪时期就从水中出现了。

Most of these are also reasonably well known, Cretaceous, Jurassic, Triassic, Silurian, and so on.

其中大多数也是相当知名, 纪, 侏罗纪, 三叠纪, 志留纪等等。

It could not be otherwise, for in the Silurian age the seas contained at least fifteen hundred vegetable and animal species.

不可能不是这样， 因在志留纪时代， 海洋中至少含有一千五百种植物和动物。

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，它在志留纪晚期和泥盆纪早期海洋中占主导地位：海蝎子。

This twofold impact known as the Ordovician-Silurian Extinction, wiped out about 25% of all taxonomic families, including about half of trilobite families.

这种奥陶纪-志留纪灭绝双重影响消灭了大约 25% 所有分类科，包括大约一半三叶虫科。

Adam Sedgwick of Cambridge claimed for the Cambrian period a layer of rock that Roderick Murchison believed belonged rightly to the Silurian.

剑桥大学亚当·塞奇威克 (Adam Sedgwick) 声, 寒武纪时期一层岩石, 罗德里克·默奇森 (Roderick Murchison) 认属于志留纪。

It's one of the earliest known fungi in the fossil record, dating back 440 million years, to the early Silurian Period.

它是化石记录中已知最早真菌之一，可追溯到 4.4 亿年前志留纪早期。

The fish fossils were discovered at two sites in Chongqing and Guizhou, whose strata date back to the Silurian Period that began around 440 million years ago.

这些古鱼化石是在我国重庆、贵州等地志留纪早期距今约 4.4 亿年地层中发现。

But that picture of the Silurian  could not have been more wrong.

但那张志留纪照片大错特错了。

These events happened at least  15 times throughout the Silurian, and we're still not actually sure why.

这些事件在整个志留纪期间至少发生了 15 次，但我们仍然不确定其中原因。

And, most of all, they show us how unpredictable  the Silurian period really could be.

最重要是，它们向我们展示了志留纪时期到底是多么难以预测。

So armored fish came in a variety of shapes and sizes during the Silurian and Devonian, from tiny Heterostracans to massive Placoderms.

因此，在志留纪和泥盆纪期间， 装甲鱼形状和大小各不相同，从微小异类鱼到巨大盾皮鱼。

The period that came next, the Silurian, saw the evolution of armor in many groups of fish, all around the same time.

接下来时期， 即志留纪，见证了许多鱼群盔甲进化，几乎是在同一时间。

Though only a few centimeters long, these graptolites would help unlock much  bigger secrets of the Silurian period.

虽然只有几厘米长，但这些笔石将有助于解开志留纪时期更大秘密。

This is because scale trees were a type of plant called lycopods, which originated way back in the Silurian Period -- before seeds were even a thing!

这是因鳞片树是一种叫做石松植物，起源于志留纪时期——甚至在种子出现之前！

Scientists imagine that these booms would have made graptolites the equivalent  of krill during the Silurian.

科学家们认，这些繁荣将使笔石相当于志留纪时期磷虾。

By the Silurian Period, a genus called Sphooceras tried a different tactic: Instead of coiling its shell, it broke off the end of it.

到志留纪时期， 一种名 Spooceras 属尝试了一种不同策略：它没有将外壳卷起来，而是折断了外壳末端。

Considering the consequences of these extinctions, it seems unbelievable that we once  thought the Silurian was so peaceful.

考虑到这些灭绝后果，我们曾经认志留纪如此和平似乎令人难以置信。