All geologic time before 600 million-years-ago. It was originally thought that this time period held no complex organisms with bodies, until Sprigg’s creatures, the earliest known organisms with true bodies, were re-dated by Martin Glaessner to be from the Precambrian era.
Precambrian Era Term Timeline in Your Inner Fish
The timeline below shows where the term Precambrian Era appears in Your Inner Fish. The colored dots and icons indicate which themes are associated with that appearance.
Chapter 7: Adventures in Bodybuilding
...Body of Evidence. Though humans may seem to have nothing in common with the early Precambrian bodies, those early bodies were actually made out of the very material that allows human... (full context)