But some might be the ancestors of the Cambrian megafauna.

但是他们中一些可能就是纪大型动物祖先。

During the Cambrian Period, many major animal groups first appeared on Earth.

纪时期，地球上首次出现许多主要生物群。

Tommotian and Burgess Shale formations give clues about Precambrian evolution.

早间，Tommotian和伯岩化石群为前纪进化提供了线索。

These findings are not of Precambrian animals themselves, but of their tracks.

发现并不是纪前动物本身，而是它们足迹。

Precambrian animals must therefore have lived at such depths.

因此，前纪动物肯定曾经生活在这么深地方。

Now go back to the Cretaceous Period and look at our tiny, fuzzball ancestors.

人类眼光不足以让我们看出它有多么特别再回到纪时期。

Alas, it turns out the Cambrian explosion may not have been quite so explosive as all that.

啊！纪大爆发被证明也许并非爆发得那样厉害。

Scientists call the period between about 541 million to 530 million years ago, the Cambrian explosion.

科学家将大约5。41亿到5。3亿年前这段时间称为纪大爆发。

In fact, we now know, complex organisms existed at least a hundred million years before the Cambrian.

实际上，现在我们知道，复杂生物至少在纪l亿年以前已经存在。

But red in tooth and claw the Precambrian was not—for neither teeth nor claws existed.

但是前纪时期却不是腥牙血爪，因为那个时候牙齿和爪子都没有出现。

But basically, you know, the 90s and internet feels like a pre-Cambrian era when there were only sponges.

但基本上，你知道，90年代和互联网给人感觉就像前纪时代，那时只有海绵宝宝。

Shortly after the Cambrian explosion, mud slides rapidly buried thousands of marine animals under conditions that favored fossilization.

在纪大爆发后不久，滑落泥土迅速掩埋了成千上万海洋动物，形成了极有利于化石形成环境。

The fall of the Ediacaran fauna was followed by the creative outburst of the Cambrian period.

埃迪亚卡拉动物群没落之后是纪创造性爆发。

Mr Volpi talks of a " Cambrian explosion" .

沃尔皮先生谈到" 纪大爆发" 。

Back in the Cambrian, new phyla and new classes arose. Nowadays we only get new species!

而在纪，新门和新纲不断产生。如今我们只有新种！”

Cambrian explosion and all this stuff.

纪大爆发和所有这些东西。

But it would take you twenty years to reach the dawn of the Cambrian period.

但是，你要花上20年时间才能抵达纪初期。

In the context of the Cambrian, explosion would soon have more to do with modern tempers than ancient physiological facts.

联系到纪氛围，“爆发”很快跟现代人脾气，而不是跟古代生理上事实更有关系。

There's a singularity and a brief burst explosionfor 40 million years of the Cambrian explosion.

纪大爆发有一个奇点和一次短暂爆发，持续了四千万年。

In fact, says Fortey, there are relatively few Cambrian designs that are wholly novel.

实际上，福泰说：“纪造型只有几种是完全新。