Section 4
The Evolutionary History of the Animal Kingdom
Book
Version 32
By Boundless
By Boundless
Boundless Biology
Biology
by Boundless
3 concepts
![Thumbnail](../../../../../../figures.boundless-cdn.com/20656/square/figure-27-04-02ab.jpeg)
Pre-Cambrian Animal Life
Early animal life (Ediacaran biota) evolved from protists during the pre-Cambrian period, which is also known as the Ediacaran period.
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The Cambrian Explosion of Animal Life
During the Cambrian period, the most rapid evolution of new animal species occurred, but the cause of this explosion is still unknown.
![Thumbnail](../../../../../../figures.boundless-cdn.com/20663/square/figure-27-04-06.jpeg)
Post-Cambrian Evolution and Mass Extinctions
The post-Cambrian era was characterized by animal evolution and diversity where mass extinctions were followed by adaptive radiations.