The new study in the journal Proceedings of the National Academy of Sciences comes from scientists at the universities of Stanford and Mexico City who published a report in 2015 declaring the world’s sixth mass extinction was already under way.
Based on their findings, the researchers now believe this mass extinction is currently accelerating and are calling for immediate global conservation actions to prevent a “catastrophic ecosystem collapse”.
Paul Ehrlich, from Stanford University in California and one of the authors on the study, said: “When humanity exterminates populations and species of other creatures, it is sawing off the limb on which it is sitting, destroying working parts of our own life-support system.
“The conservation of endangered species should be elevated to a national and global emergency for governments and institutions, equal to climate disruption to which it is linked.”
More than 400 vertebrate species became extinct in the last 100 years – extinctions that would have taken up to 10,000 years in the normal course of evolution, the researchers said.
Examples include the ivory billed woodpecker, and the Round Island burrowing boa and, more recently, the golden toad.
Lead author Gerardo Ceballos, from the University of Mexico, said: “What we do to deal with the current extinction crisis in the next two decades will define the fate of millions of species.
“We are facing our final opportunity to ensure that the many services nature provides us do not get irretrievably sabotaged.”
Reader Q&A: Has an animal ever evolved itself into extinction?
Asked by: Matthew Cox, Wantage
It’s quite hard for a predator to drive itself extinct simply by being such a good hunter that it eats all of the available prey. Normally, evolution is a very slow process and predators are engaged in an ongoing arms race with their prey, who are also evolving new ways to escape.
If the balance starts to shift in favour of the predator, the amount of available food dwindles and the predators aren’t able to raise as many young. This allows the prey population to recover and equilibrium is restored.
But when a predator specialises to hunt a single prey species, it can get trapped in an evolutionary dead end. This happened to the Haast’s eagle in New Zealand, which had evolved to prey exclusively on the flightless moa bird. When humans arrived in the 13th Century, the moa were hunted to extinction within 200 years. The Haast’s eagle couldn’t adapt to find new prey and went extinct too.
This phenomenon, known as ‘coextinction’, is also common with parasites that have adapted to live on a single host animal.
Alexander is the Online Editor at BBC Science Focus and is the one that keeps sciencefocus.com looking shipshape and Bristol fashion. He has been toying around with news, technology and science on internet for well over a decade, and sports a very fetching beard.