Biodiversity and the sixth mass extinction: lessons from the past

University of Bath

Today we face a mass extinction that is set to devastate biodiversity across the globe. In the geological past, five similar mass extinctions events have destroyed swathes of biodiversity, so a key way we can understand this sixth crisis is by studying the evolutionary patterns during these cataclysmic events in deep time.

Mark will combine information from living and fossil species to identify if particular species’ traits and lifestyles made them more vulnerable during previous mass extinction events. At normal times, selection pressures acting on traits and lifestyles largely determine which species prosper and which go extinct. During mass extinctions, these same selective pressures may continue to determine species loss and survival. Alternatively, the huge environmental changes in short space of time could mean survival is down to luck, not selection, as species are wiped-out in a ‘random field of bullets’. In this research, Mark will test which of these processes determines survival during past events.

During the fellowship Mark will use comparative phylogenetic methods and statistical analyses of the fossil record to examine whether species’ size or shape makes them more vulnerable to extinction, and how processes of evolution respond to mass extinctions. Evolutionary patterns during mass extinctions will be analysed in a variety of groups, including mammals and reptiles, using a range of novel methods. By understanding these past processes, we can attempt to predict the outcomes of the current sixth mass extinction.