542- 488.3 Mya
The Cambrian Period is also know as the Cambrian Explosion, because of the short time over which this diversity of forms appears.
Cathaymyrus is a genus of Early Cambrian cephalochordate known from the Chengjiang locality in China. Both species have a long segmented body with no distinctive head.
Trilobites are a fossil group of extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest known groups of arthropods
The halkieriids are a group of fossil organisms from the Lower to Middle Cambrian.
The climate was colder the average temperature was 54º Fahrenheit, because it follows the Vendian period the continents are just starting to break away from the super continent Rodinia. In the Cambrian oxygen was first introduced into the oceans. Had the shallowest seas. There were a lot of underwater mountain ranges.
Gentle giants of the Cambrian