Overview
- The Science study, published Thursday, details more than 700 carbonaceous-film fossils from Yunnan dated between 554 and 539 million years ago.
- Finds include possible early deuterostomes—the group that later gave rise to vertebrates and starfish—and many bilaterians with visible guts and feeding or movement parts.
- The carbon-rich preservation, similar to Burgess Shale sites, captured whole soft bodies and suggests earlier Ediacaran sites missed such animals because they fossilize poorly.
- The work shifts evidence of complex animal life at least about 4 million years earlier than thought and frames the Cambrian explosion as a stepwise transition.
- Researchers say formal descriptions and placement of the many unfamiliar forms will take years, and some outside experts caution that a few animal IDs may be uncertain.