Until Now
BiologyGeology

The Cambrian ends

Fifty-two million years after it began, the great burst of body plans is over — and diversity is about to soar.

When
Known to
± 1 million years
Era
Ordovician, Paleozoic

The Cambrian closes at 486.85 million years ago with marine ecosystems recognisably modern in structure: predators, filter feeders, burrowers, reef builders and swimmers. What follows is not the invention of new body plans but an enormous expansion within them — the Great Ordovician Biodiversification Event will multiply the number of marine families several times over without producing a single new phylum.

Just before

Just after