The Cambrian Explosion


(530 Million years ago - year 89 on the 100 year time-scale)
The first simple life forms seem to have appeared much sooner on Earth than previously assumed, actually almost as soon as the planet became stable enough, with a stable crust and enough water for some primal oceans, some 3.800 million years ago.
However it then took over 2.000 billion years for these simple creatures to evolve to more complex organisms, which suddenly thrived in what is called the Cambrian Explosion, only some 500 million years ago.

Around 530 million years ago, a wide variety of animals burst onto the evolutionary scene in an event known as the Cambrian explosion. In perhaps as few as 10 million years, marine animals evolved most of the basic body forms that we observe in modern groups. Among the organisms preserved in fossils from this time are relatives of crustaceans and starfish, sponges, mollusks, worms, chordates, and algae.


Gentle giants of the Cambrian