Fossils discovered near Fuxian Lake in Yunnan, China, provide new insights into the origins of animal life, indicating that complex groups existed just before the Cambrian period. These fossils, part of the Jiangchuan Biota, include over 700 species and date back approximately 7 million years before the Cambrian explosion. The fossils are primarily small impressions rich in carbon, preserving intricate details, including what appear to be internal organs. This discovery suggests a gradual transition to the Cambrian rather than a sudden diversification of life forms, challenging previous assumptions about the timeline of animal evolution. The site, previously known for its abundant algae, is located within the Dengying Formation, which contains deposits from the Ediacaran period (635 to 540 million years ago).