08 April 2015
The April 2015 Sprigg lecture at the SA Museum was given by Dr Dr Diego García-Bellido and entitled ‘From the Cambrian of Kangaroo Island to the Ordovician of Morocco’.
The Cambrian (541–485 million years ago or ‘Ma’) and the Ordovician (485–458 Ma) periods represent a crucial phase in the history of the Earth: they bring the sudden appearance of most major animal groups, together with unprecedented anatomies and functionalities.
The initial phase of diversification of metazoans, the ‘Cambrian Explosion’, brought the appearance of very high-level taxonomic groups – Phyla and Classes – and was followed by a second burst of marine biodiversity called the ‘Great Ordovician Biodiversification Event’, or GOBE, which produced an dramatic increase at the Order and Family and Genus levels and a significant rise in the complexity of the ecosystems.
Diego García-Bellido's lecture looked at the information provided by Cambrian fossils from such localities as the Burgess Shale in Canada, Chengjiang in China and Emu Bay Shale in Australia, and compared them with the new Ordovician soft-bodied faunas discovered in Morocco - the Fezouata and Tafilat biotas.