Cambrian explosion: Quick Facts

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Last updated

Oct. 22, 2026

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Algae fossils from Cambrian explosion hint at sophisticated reproductive system • Oct. 19, 2026, 10:30 AM ET (Phys.org)

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A colorful diagram of the geologic time scale shows major eons, eras, and periods, with illustrations of key prehistoric life forms such as bacteria, jellyfish, trilobites, fishes, dinosaurs, mammals, and humans, spanning from 4,000 million years ago to the present. Measurement bars at the top and bottom indicate the passage of time in millions of years, and each section is color-coded to highlight evolutionary milestones.

Illustration of Anomalocaris canadensis, a soft-bodied Cambrian predator, showing its elongated segmented body, large frontal appendages, circular mouth, and prominent eyes, with a simplified top view inset.

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Topics

Cambrian Period Ordovician radiation evolution human evolution Lamarckism What Darwin Got Right (and Wrong) About Evolution last universal common ancestor adaptation extinction coevolution inclusive fitness mutation theory emergence