How ocean ecosystems recovered after mass extinction event 66 million years ago

An international team of scientists, led by the University of Bristol, have produced an unprecedented record of the biotic recovery of ocean ecosystems that followed after the last mass extinction, 66 million years ago. In an article published in the journal Nature , the team, which includes researchers from Southampton, University College London, Frankfurt and California, present a 13 million-year record of fossil plankton dynamics in the aftermath of near annihilation, providing a remarkable glimpse into how the marine ecosystem 'reboots'. The Cretaceous/Paleogene (K/Pg) mass extinction occurred when an asteroid impact caused global environmental devastation and is well known for the extinction of dinosaurs, ammonites and many other groups. But, as well as the loss of these larger animals, there were equally devastating extinctions in the ocean plankton, which removed food production at the base of the marine ecosystem and crippled important ocean functions, such as the delivery of carbon to the deep-sea, which is a critical control on atmospheric carbon dioxide. Lead author, Sarah Alvarez, who carried out the research at Bristol's School of Geographical Sciences and is now based at the University of Gibraltar, said: "We wanted to find out how long the ocean ecosystems took to recover and how this happened. "We looked at the best fossil record of ocean plankton we could find - calcareous nannofossils (they are still around today) - and collected 13 million years of information from a sample every 13,000 years.