Possible patterns of marine primary productivity during the Great Ordovician Biodiversification Event

Alexandre Pohl (1) , David Harper , Yannick Donnadieu (1) , Guillaume Le Hir (2) , Elise Nardin (3) , Thomas Servais (4)

1 Plateforme de géochimie isotopique ASTER-CEREGE
2 IPGP - Institut de Physique du Globe de Paris
3 GET - Géosciences Environnement Toulouse
4 Evo-Eco-Paléo (EEP) - Évolution, Écologie et Paléontologie (Evo-Eco-Paleo) - UMR 8198

Following the appearance of numerous animal phyla during the 'Cambrian Explosion', the 'Great Ordovician Biodiversification Event' (GOBE) records their rapid diversification at the lower taxonomic levels, constituting the most significant rise in biodiversity in Earth's history. Recent studies suggest that the rapid rise in phytoplankton diversity observed at the Cambrian-Ordovician boundary may have profoundly restructured marine trophic chains, paving the way for the subsequent flourishing of plankton-feeding groups during the Ordovician. Unfortunately, the fossil record of plankton is incomplete. Its smaller members represent the bulk of the modern marine biomass, but they are usually not documented in Palaeozoic sediments, preventing any definitive assumption with regard to an eventual correlation between biodiversity and biomass at that time. Here we use an up-to-date ocean general circulation model with biogeochemical capabilities (MITgcm) to simulate the spatial patterns of marine primary productivity throughout the Ordovician, and we compare the model output with available palaeontological and sedimentological data.-160

Domaines: Paléontologie; Climatologie; Océan, Atmosphère; Biodiversité et Ecologie; Milieux et Changements globaux

Alexandre Pohl, David Harper, Yannick Donnadieu, Guillaume Le Hir, Elise Nardin, et al.. Possible patterns of marine primary productivity during the Great Ordovician Biodiversification Event. Lethaia, 2018, 51 (2), pp.187-197. ⟨10.1111/let.12247⟩. ⟨hal-02408744⟩