Earth’s recovery from climate change could take ‘millions of years’

The Earth could take millions of years to recover from the mass extinctions which are being caused by climate change, a new study has revealed.

Research conducted by the University of Bristol and University of Texas investigated the recovery rate of planktic foraminifera from the Cretaceous-Paleogene extinction – to date the only global event comparable with current climate change.

The study found that it took the world’s species around ten million years to recover from the extinction, which killed the dinosaurs and left a hole in the biosphere.

Those behind the study said the findings have clear implications for the present climate crisis, with natural habitats increasingly being destroyed.

Researcher and co-author of the study, Andrew Fraass, said: ‘Foraminifera are useful at the species level because of their superior fossil record, so we’ve been able to look at this process in a closer way than anybody else.

‘From this study, it’s reasonable to infer that it’s going to take an extremely long time – millions of years – to recover from the extinction that we’re causing through climate change and other methods.’

The two universities took measurements from foraminifera to see how similar or different species were following the extinction, focusing on around 20 million years after the event.

The researchers found that there was a ‘speed limit’ in the world’s recovery from mass extinction, with small, simple and diverse innovations in species having to develop first.

Once those species refilled broader niches in the ecosphere, more specialist species with smaller variations began to reappear, filling in the gaps around those first sets.

The study confirms earlier theoretical research by two other authors and offer a perspective on how the world fared in the past and will in the future.

Fraass added: ‘We’re hoping that examining the rest of the planktic foraminiferal record will give us insight into how climate shaped their evolution.

‘With the past, slower, changes in climate we have in the geological record, we should be able to tease out more details about how climate change might impact these important plankton.’

The co-authors now plan to look at the rest of the history of the foraminifera group, from the late Jurassic period to the present day.

A 2018 report found that global wildlife populations have declined by over half in the last 50 years, largely due to human activity such as habitat loss, pollution and climate change.

The latest Living Planet assessment, conducted biennially by the Zoological Society of London (ZSL) and the WWF, found that wildlife population sizes decreased by 60% between 1970 and 2014, with animals living in lakes, rivers and wetlands suffering the biggest losses.