Six hundred million years ago a remarkable eruption of new lifeforms occurred within the oceans. These species were the first to show signs of having skeletons and are recognised as the founders of all modem groups of animals. What caused this transformation and what forces have shaped the history of life since then?
At a recent Dahlem symposium held in Berlin, evolutionary biologists, palaeontologists and geologists gathered to discuss these questions.
Colin Tudge investigates. Producer JULIAN BROWN
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