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Environment

Sixth wave of mass extinction?

A new study indicates humans are driving an unprecedented wave of species extinction. Scientists say it will take a concerted global conservation effort to prevent what would otherwise be inevitable.

The term "sixth wave of extinction" rings with the promise of dramatic science fiction. But there is nothing fictional about the report published in the latest edition of the journal "Science Advances." On the contrary, the findings of the paper, entitled "Accelerated modern human-induced species losses," paint an earnest picture of a depopulated dystopian future.

The work, conducted by scientists from three United States universities - Princeton, Berkeley and Stanford - suggest that the planet has not shed its species at such a rate since the eradication of dinosaurs some 66 million years ago. That was the fifth mass extinction since earth's beginnings - and the first-ever whose origins can be traced back to a single species: humans.

Using what they describe as "conservative assumptions" to assess the impact of human activities on the ever-increasing depletion of our natural world, the authors said there is undeniable evidence that modern extinction rates have increased sharply over the past 200 years - in step with an increasingly industrialized society.

Drought leaves dead and dying animals in northen Kenya, Africa

No water, no life

They arrived at their conclusions by comparing current figures with historical data relating to the extinction of vertebrates. The results of the report suggest that modern vertebrate extinctions between 1500 and 1900 would have taken "several millennia" to happen if the rate from that period had remained constant.

But that is not what happened. Rather, the past 114 years have seen an exponential rise in extinction rates. The report's researchers say 468 more vertebrates have become extinct than would have if the historical rate - two species per 10,000 over a 100 year period - had continued at pre-1900 levels. And they predict a continuation of the same scenario unless the world unites in a targeted effort to change course.

Humans: threat - and threatened

According to the International Union for Conservation of Nature (IUCN), some 41 percent of amphibians and 26 percent of mammal species are currently facing extinction. Some of the world's most beloved species are among them.

Those figures are additional to the 338 species known to have been wiped out since 1500, and the additional 279 the organization deems either "extinct in the wild" or "possibly extinct."

Gerado Ceballos, lead author of the study, told DW that while he was expecting to see a significant correlation between human enterprise and biodiversity loss, he had not expected it to be so extreme.

"There are too many people - and the number is growing - and they are not using natural resources well," he said, adding that habitat exploitation is continuing. "There is also the problem of invasive species, and of course climate change, which is becoming another major issue."

Add to that the explosion in illegal wildlife trade - which now ranks as one of the five most lucrative circles of crime in the world - and humans emerge not merely as exploiters, but also cruel ones to boot.

Dead fish float in the water

Pollution is one of the key problems facing the world's wildlife

Against that backdrop, perhaps the greatest irony embedded in the findings is the prediction that one of the earliest casualties will be none other than humans themselves. It is unlikely, Ceballos adds, that we will disappear altogether. Rather, he believes that civilization as we currently understand it might.

"All species are part of the function of nature, and it provides us with free services such as a quality and quantity of fresh water," he said. "But if we don't do something really fast, within the next three to four decades, all the benefits we have now may be jeopardized by a loss of species."

Knowledge versus action

That there is an urgent need for action is evident, but exactly what form it should take remains unclear. This is in part because the contributing factors are so diverse, but also because different species are facing different challenges. There is no single remedy.

Arnulf Köhncke, Species Conservation Expert at WWF Germany, advocates increasing awareness across the board and tapping into a public consciousness, while simultaneously appealing to policymakers. He welcomes a recent surge in media coverage of biodiversity loss, but condemns how this tends to focus on one issue at a time.

"Positive reactions are generally to specific issues such as the illegal wildlife trade, which has received a lot of political and financial support lately," he told DW.

A ranger holding a gun watches over rhinos

Slaughtered for their horns, rhinos have become the target of criminal gangs

He hopes the United Nations Climate Conference in Paris at the end of the year will provide a platform for fleshing out what he describes as "ambition goals" that a longer view of the overall situation.

Failure to do so could have devastating consequences for our natural habitat, and the species with which we share it. Ceballos agrees that the problem needs global political commitment, but also says it is up to every single one of us to do what we can to avert the decay and loss of ecosystem services. For that, he calls on the world to use its resources wisely - and on consumers to change their habits.

"We are the ones causing these problems," he said. "We are also the only ones who can stop them."

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