London - A Cambridge scientist and two Chinese colleagues have pushed the history of all vertebrates back by at least 50 million years. They have identified fossils of two previously unknown species of fish in rocks laid down in what is now south China 530 million years ago.
This is the first evidence of vertebrates in what is known as "the Cambrian explosion". Until about 600 million years ago, life on earth was composed mainly of microbes and other very simple organisms.