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。

Precambrian animals must therefore have lived at such depths.

因此，前寒武纪的动物肯定曾经生活在这么深的地方。

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

发的并寒武纪前的动物本身，而它们的足迹。

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

但前寒武纪时期却牙血爪，因为那个时候牙齿和爪子都没有出。

The schoolboy turned it in to a paleontologist at the University of Leicester, who identified it at once as Precambrian.

那位小学生把化石交给莱斯特大学的一位古生物学家。他马上认出那寒武纪之前的东西。

On this scale, according to John McPhee in Basin and Range, the distance from the fingertips of one hand to the wrist of the other is Precambrian.

按照这个比例，据约翰·麦克菲在《海洋和山脉》一书中说，一只手的指尖到另一只手的手腕之间的距离代表寒武纪以前的年代。