Huayuan soft-bodied Cambrian biota reveals a diverse deep-sea ecosystem after the first Phanerozoic mass extinction

The Huayuan biota, a lower Cambrian Burgess Shale–type Lagerstätte from the Yangtze Block in South China, preserves 153 animal species across 16 phyla—51% or more new—mostly soft-bodied with preserved cellular tissues, including radiodonts and pelagic tunicates. This high-diversity, deep-water assemblage, dated shortly after the Sinsk event, links to Burgess Shale faunas via transoceanic dispersal and illuminates Cambrian ecosystem transitions between Ages 3 and 4 and the differential impacts of the first Phanerozoic mass extinction in shallow versus deep settings.