Paper No. 76-2
Presentation Time: 8:15 AM
CO-EVOLUTION OF PLATE TECTONICS AND LIFE: THE BIOGEODYNAMIC PERSPECTIVE ON THE MESOPROTEROZOIC-NEOPROTEROZOIC TRANSITIONS
There is growing understanding that life evolution on Earth is intimately related to and shaped by the global tectono-magmatic style that evolved through geological time until modern plate tectonics was established in the Neoproterozoic, between 1000 and 541 million years ago. The co-evolution of life and tectonics on Earth is the subject of Biogeodynamics – an emerging field at the interface between the disciplines of geodynamics, geomorphology, climate, ocean and atmosphere sciences, geobiology and ecology with special focus on how evolution of the planetary interiors, surface, atmosphere, ocean, climate, and life are interrelated. In particular, biogeodynamics seeks to investigate different plausible global and regional geodynamical evolution scenarios to gage their influence on biosphere evolution as expressed by biodiversity. In this presentation we will review the state of the art for our understanding of co-evolution of modern plate tectonics and complex life. We start by explaining what Biogeodynamics is, then explain what are modern plate tectonics and single lid tectonics and how these differ, and then discuss how plate tectonics controls global terrestrial biodiversity today. We summarize first biodiversity in the Mesoproterozoic and Neoproterozoic, including how evolution accelerated remarkably in the Neoproterozoic, then summarize geological evidence for a protracted Mesoproterozoic single lid that was slowly transformed in Neoproterozoic time into the modern global plate tectonic mosaic. Evidence for a protracted transition to Cryogenian and younger Plate Tectonics from Mesoproterozoic and Tonian single lid tectonic regime will be presented. We next explore how the Neoproterozoic tectonic revolution enhanced five factors that accelerated biological evolution: 1) increased nutrient supply; 2) increased free oxygen in the atmosphere and ocean; 3) climate amelioration; 4) accelerated habitat formation and diversification; and 5) moderate sustained environmental pressure. Finally, we suggest some avenues for future Biogeodynamic research into the co-evolution of Earth’s tectonics and Biosphere.