中国科学院南京地质古生物研究所机构知识库

Non-lithistid spiculate sponges were major components of Cambrian and Ordovician communities, but currently there is limited understanding of how sponge distribution patterns developed during the Cambrian Explosion and the Great Ordovician Biodiversification Event (GOBE). We compiled data on Cambrian and Ordovician sponge occurrences from the literature and our own research. Sponge genera were widely distributed during the Cambrian Period, with broadly consistent assemblages between palaeocontinents, from different palaeolatitudes, and over a timespan of approximately 25 Myr. Sponges exhibited a marked shift from cosmopolitan to highly endemic genera during the Tremadoc and later Ordovician. Surviving Cambrian genera continued to be very widespread, but taxa that originated during the Ordovician had much narrower geographic and environmental ranges, perhaps related to the origination of modern-style, patchy ecology. The cosmopolitanism of the Cambrian faunas is suggestive of rapid dispersal of recently evolved groups without competition from pre-existing sponges, suggesting that sponges had not diversified during the Precambrian. In contrast, the Ordovician record indicates local diversification against a complex ecological backdrop. Based on the ecological record of sponges, the Cambrian Explosion was a fundamentally different process to the GOBE. (C) 2018 Elsevier Ireland Ltd Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Published by Elsevier B.V. All rights reserved.