Oxford study suggests animals may have evolved 200 million years earlier

The oldest definitive animal fossils date to around 574 million years ago, just before the dramatic diversification associated with the Cambrian Period. The animal kingdom may have started its journey on a much earlier Earth than scientists once thought. Long before recognisable creatures appeared in the fossil record, and perhaps before the planet was plunged into some of its most severe ice ages, primitive animals may already have been quietly evolving in ancient seas. A new study led by the University of Oxford suggests that animal life could have originated between 700 million and 800 million years ago, potentially 200 million years earlier than the clearest fossil evidence indicates. Published in Science Advances, the research challenges one of the assumptions that has shaped recent estimates of when animals first emerged.The problem with a missing fossilThe fossil record gives scientists an incomplete picture of early animal life. The oldest definitive animal fossils date to around 574 million years ago, just before the dramatic diversification associated with the Cambrian Period. One important site in this debate is the Weng’an Biota in China, a roughly 590-million-year-old ...