Precambrian time covers the vast bulk of the Earth's history, starting with the planet's creation about 4.5 billion years ago and ending with the emergence of complex, multicelled life-forms ...

Paleontologists now know that the Precambrian actually did swarm with ... However life got started, it had to have been in full swing by the time it left its mark in the Greenland rocks.

The Precambrian encompasses 86 percent of the history of Earth. As its name implies, this includes all of geological time prior to the Cambrian period. Hadean Era (4,550-3,850 mya) The Precambrian ...