Animals may have evolved 200 million years earlier than thought

A University of Oxford-led study published in Science Advances challenges the assumption that the absence of animal fossils at China's 590-million-year-old Weng'an Biota proves animals had not yet evolved. Using microfossils from Mongolia's Kheseen Biota and molecular clock analysis, researchers place the possible origin of animals at 800–700 million years ago.

• Estimated origin of animals pushed back to 800–700 million years ago
• Kheseen microfossils are as well preserved as Weng'an but contain no animals
• Biomarkers suggest sponges existed at least 650 million years ago
• Animals may predate or overlap the Cryogenian Snowball Earth glaciations