dramatically. It was the time of the Cambrian Explosion, an eruption of life when Earth’s very first animals began appearing in the fossil record — the ancestors of all major animal groups ...

with the eventual appearance of the lineages of almost all animals living today. This stunning and unique evolutionary flowering is termed the "Cambrian explosion," taking the name of the ...

The Cambrian Explosion saw an incredible diversity of life emerge, including many major animal groups alive today. Among them were the chordates, to which vertebrates (animals with backbones ...