More than 500 species are on the verge of extinction in the 20 years as a result of human activities, according to a new study published on 1 June in the journal Proceedings of the National Academy of Sciences (1). The sixth mass extinction of wildlife is occurring much faster than previously thought and could have devastating effects on ecosystems, the authors warn.
Humans depend on biodiversity and the many services that ecosystems provide. Prof Paul Ehrlich of Stanford University, who co-authored 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.”
The researchers from Stanford University and Mexico City University used data from the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species and from Birdlife International to examine the abundance and distribution of critically endangered species. The analysis follows a previous report published by the same team in 2015 proclaiming that the world’s sixth mass wildlife extinction is already underway (2).
Out of 29,400 species analysed, the new study identified 515 land-based vertebrate species with less than 1,000 individuals remaining and around half of these had fewer than 250 remaining. Most are located in areas of tropical and subtropical regions that are particularly affected by human activities, such as the wildlife trade, population growth, habitat destruction, pollution, and climate change. These problems must be tackled to prevent further loss of wildlife. Unlike other environmental problems, the extinction of wildlife cannot be reversed, the authors note.
More than 80 per cent of species with populations of less than 5,000 live in the same areas as those with populations under 1,000, which could result in a deadly cascade, or ‘domino effect’, the authors wrote. In other words, extinctions will trigger co-extinctions leading to further loss of biodiversity.
In the past century, more than 400 species have gone extinct, which normally would have taken thousands of years without human destruction of nature, the researchers said. Now, the same huge losses of species are likely to occur over the next two decades. Some of the land vertebrates on the brink of extinction include the Sumatran rhino, the Clarión wren, the Española giant tortoise, and the harlequin frog.
The study provides evidence that wildlife extinction is occurring at an unprecedented rate not seen since the death of the dinosaurs around 65 million years ago. The scientists call for immediate global conservation actions to prevent a ‘catastrophic ecosystem collapse’.
Lead author Gerardo Ceballos of 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.”
Prof Paul Ehrlich of Stanford University, who co-authored 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.”
(1) Ceballos, G., Ehrlich, P.R. and Raven, P.H. Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction. Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.1922686117
(2) Ceballos, G. et al. Accelerated modern human-induced species losses: Entering the sixth mass extinction. Sciences Advances (2015). DOI: 10.1126/sciadv.1400253
Photo credit. Sumatran Rhinoceros (Dicerorhinus sumatrensis) by Willem V. Strien
Paul Ehrlich is the famous author of The Population Bomb. So it is surprising that he doesn’t argue to control human birth again. Maybe because he found that the endangerous species are located on tropical and equatorial zones, principally.
But if the problem is local, why is he calling for a global emergency? And I don’t understand how scientists manifesting in the street could solve anything.
Rhinos don’t live in streets, extinction rebellion activists do.
I think we should let local governements, local people, local scientists deal with their endangered species. Local people knows better, and pandas, jaguars, girafas are distinct things. WWF, greenpeace, BBC nature, Dian Fossey and global actors had not proven their ability to protect species efficiently, unfortunately. They failed in identifying the real drivers of extinction.