But it was not as rapid as an explosion: the changes seems to have ... It has long been suspected that the sparseness of the pre-Cambrian fossil record reflects these two problems.

This finding agrees with the Cambrian explosion—a period between 541 and 485 million years ago that saw an unparalleled rise in evolutionary diversity. Although scientists had long suspected ...

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 ...

Then, about 540 million years ago, something else changed ... dramatically. It was the time of the Cambrian Explosion, an eruption of life when Earth’s very first animals began appearing in the ...