European Molecular Biology Laboratory (EMBL)'s video: EMBL Keynote Lecture: The evidence for mass extinctions

Presenter: Michael Benton, University of Bristol, UK From EMBL Science and Society Conference: Our House is Burning: Scientific and Societal Responses to Mass Extinction Virtual 4 – 5 Nov 2020 ABSTRACT: Palaeontologists have studied mass extinctions for over fifty years, and substantial clarity has emerged on many points. Whereas causation was debated, two models have emerged – impact-driven crisis (one event, 66 Myr ago) and volcanism-driven crises (many events, including 252, 232, 201 Myr ago). In terms of patterns, geologists have refined their knowledge of age-dating, environmental change (changing climate, rapidity of change, post-crisis stabilization), and impacts on life (proportional losses, selectivity by ecology and palaeogeography, rate and nature of recovery). The volcanic model shows common features of warming (by up to 10oC), humidity, acid rain, stripping of forests and soils, ocean acidification and anoxia. These documented components of the consequences of huge volcanic eruptions can all be tested and confirmed, and they coincide with many of the current anthropogenic-caused changes to the atmosphere-ocean system. This means that investing effort in refining our knowledge of how global environments change, how the changes kill life, and how the Earth and life recover afterwards can inform our understanding of the current and near-future.