The Anji Biota: the secret history of glass sponges

Hexactinellids, or 'glass sponges', are a major group of deep-sea animal, but their history is poorly known. Upper Cretaceous rocks yield many examples that look similar to the modern groups, but before that the record is extremely sparse... The Anji Biota (latest Ordovician) has produced a high diversity of sponges, which, astonishingly, includes many species that look very similar to modern hexactinellids. This video explores how thais transforms our understanding of their evolution, and how the modern fauna is but a relic of a relic of their former glory... Relevant videos Sponges introduction:    • Sponges: the essentials   Hexactin problem:    • Sponges: the hexactin problem and its impo...   Anji Biota:    • The Anji Biota: mass extinction, but spong...   Papers (mostly not open access, sorry!) Anjiplectella: https://onlinelibrary.wiley.com/doi/a... Anji rossellids: https://onlinelibrary.wiley.com/doi/a... stem-group rossellid Matteolaspongia: http://www.geology.cz/bulletin/fullte... Presented by Joe Botting, independent palaeontologist and Honorary Research Fellow at the National Museum Wales. ---------------------------------------------------------------------------------------------------------------------------------------------------- Channel Membership: to support the channel for £3.99 per month, please investigate the 'join' button underneath the video. You can expect 2-3 extra videos per month, showing current research, related mainly to the Ordovician Castle Bank Biota.