Tommotian and Burgess Shale formations give clues about Precambrian evolution.

早间，Tommotian和伯吉斯页岩化石群为前寒武纪进化提供了线索。

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

但是前寒武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。

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

发现的并不是寒武纪前的动物，是它们的足迹。

Precambrian animals must therefore have lived at such depths.

因此，前寒武纪的动物肯定活在这么深的地方。

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

但基上，你知道的，90年代和互联网给人的感觉就像前寒武纪时代，那时只有海绵宝宝。

In northern Australia, there hasn't been any new mounted buildings since the pre-Cambrian era that ended one and a half billion years ago.

在澳大利亚北部，自 15 亿年前的前寒武纪时代结束后，就再也没有出现过新的建筑。

They first show up in the fossil record during  the Cambrian period, over 500 million years ago.

它们首次出现在化石记录中是在 5 亿多年前的寒武纪时期。

He told the Associated Press it is believed that " … modern animal groups like jellyfish appeared 540 million years ago in the Cambrian explosion."

他告诉美联社，据信“… … 诸如水母之类的现代动物群体出现在5。4亿年前的寒武纪大爆发期间。”

Life on earth has existed for 4 billion  years, mostly as single celled organisms until some 540 million years ago the Cambrian  explosion heralded the age of animals.

地球上的命已存在了 40 亿年，大部分都是单细胞物，直到大约 5.4 亿年前的寒武纪大爆发预示着动物时代的到来。

Nowadays, and speaking very generally, geological time is divided first into four great chunks known as eras, Precambrian, Paleozoic, from the Greek meaning old life, Mesozoic, middle life, and Cenozoic, recent life.

现在, 一般来说, 地质时间首先分为四个大块, 称为时代, 前寒武纪, 古代, 来自希腊语, 意思是旧活, 中代, 中代和新代, 最近的活。

One of the most famous stories of life returning from the depths of time starts over half a billion years ago, in the Cambrian Period, right when life was getting its feet under it.

最著名的命从时间深处回归的故事之一始于 50 多亿年前的寒武纪，当时命刚刚开始在它的脚下站稳脚跟。