Extinction domino effect linked to climate change


Environmental changes increase the risk of an ‘extinction domino effect’ that could annihilate all life on Earth, according to new research.

Researchers, including CABAH Chief Investigator Professor Corey Bradshaw, simulated 2,000 ‘virtual Earths’ linking animal and plant species. Using sophisticated modelling, they subjected the virtual Earths to catastrophic environmental changes, including runaway global warming, scenarios of ‘nuclear winter’ following the detonation of multiple atomic bombs, and a large asteroid impact.

“What we were trying to test is whether the variable tolerances to extreme global heating or cooling by different species are enough to explain overall extinction rates,” Prof Bradshaw explains.

“But because all species are connected in the web of life, our paper demonstrates that even the most tolerant species ultimately succumb to extinction when the less-tolerant species on which they depend disappear.”

Even sturdy tardigrade-like species like the tiny 'water bear' were vulnerable to the extinction domino effect in the study
2,000 virtual Earths were created
and populated with thousands of virtual species
Catastrophic environmental changes
were simulated to test resilience of the species

“Not taking into account this domino effect gives an unrealistic and exceedingly optimistic perspective about the impact of future climate change."

“Failing to take into account these co-extinctions, therefore, underestimates the rate and magnitude of the loss of entire species from events like climate change by up to 10 times,” Professor Bradshaw adds.

The research by Professor Bradshaw and Dr Giovanni Strona of the European Commission’s Joint Research Centre based in Ispra in northern Italy is published in the journal Scientific Reports.

“Not taking into account this domino effect gives an unrealistic and exceedingly optimistic perspective about the impact of future climate change”, warns Professor Bradshaw, CABAH Models Theme Leader.

It can be hard to imagine how the demise of a small animal or plant matters so much, but tracking species up to total annihilation demonstrates how the loss of one can amplify the effects of environmental change on the remainder, he says.

Professor Bradshaw warns that the modelling shows how climate warming creates extinction cascades in the worst possible way, when compared to random extinctions or even from the stresses arising from nuclear winter.

The virtual plants and creatures in the study were based on data from more than 450 warm-blood species, almost 240 cold-blooded species and 4,445 plant species. They included 100 so-called ‘extremophiles’ tardigrade-like species –that previous research suggested could survive the harshest environments on Earth.

However, Professor Bradshaw adds: “Our work shows that their remarkable tolerances to heat and cold still don’t protect them from ecological meltdown driven by co-extinctions.”

Share this Article