New research shows, after a mass extinction event 66m years ago, plankton were disrupted for nearly 2m year, taking a further 8m for their population to recover.
Researchers, from the University of Southampton, University of Bristol, University College London, University of Frankfurt and University of California, discovered that although the plankton in the ocean showed signs of recovery almost immediately after the extinction event, these microscopic organisms were highly unstable with unusually small cell sizes.
The Cretaceous/Paleogene mass extinction is thought to have occurred with and asteroid collided with the earth causing intense and catastrophic damage to the ecosystems that inhabit it. In addition to killing the dinosaurs, the collision devastated small organisms living on earth, one of which being the plankton. After the destruction on the base of the ecosystem, the plankton, it made the recovery of larger marine animals seem almost impossible.
2m years after the extinction event, the plankton began to recover, reducing the atmospheric CO2 levels and allowing larger more complex beings to gradually increase, re-establishing a once thriving ecosystem.
The scientists conducting the study charted the aftermath of this extinction event using fossil records from 13m years ago. Lead author Sarah Alvarez (University of Bristol, UCL and now Gibraltar) explains: “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 thousand years. We measured abundance, diversity and cell size from over 700,000 fossils, probably the largest fossil dataset ever produced from one site.”
Palaeobiologist and co-lead author, Dr Samantha Gibbs of the University of Southampton comments: “Losing species today runs the risk of eliminating key creatures in ecosystems. What we’ve demonstrated from this fossil record is that function is achieved if you have the right players fulfilling key roles.
“Today, by reducing biodiversity, we are running the risk of losing our critical ecosystem players, many of whose importance we don’t yet fully appreciate.”