Research shakes up Cambrian explosion

Paleontology is on the move, thanks to a study from the Universities of Lausanne (Unil) and Oxford. It calls into question the period known as the "Cambrian Explosion", between 540 and 500 million years ago, during which it is accepted that all groups of animals appeared. According to the Lausanne-based experts, this was not an explosion, but a slow deflagration...