Paleozoic Era

Cambrian Period

541–485 Million Years Ago

The Cambrian Period marks the explosive diversification of animal life known as the Cambrian Explosion. Within a relatively brief span, most major animal phyla appeared in the fossil record for the first time. The oceans teemed with trilobites, anomalocaridids, and bizarre creatures preserved in extraordinary detail in deposits like the Burgess Shale. This period laid the groundwork for all subsequent animal evolution.

Environment

Climate & Environment

Warm greenhouse conditions with high sea levels. Most continents were clustered in the southern hemisphere, surrounded by the vast Panthalassic Ocean.

Fauna & Flora

Signature Life Forms

Trilobites — dominant marine arthropods

Anomalocaris — apex predator of Cambrian seas

Hallucigenia — iconic Burgess Shale oddity

First chordates and early vertebrate ancestors

Cambrian

paleozoic