A new study has confirmed mankind’s role in the steady decline of species worldwide.
Slowly but surely, the phrase “Sixth Extinction” has been creeping into the mainstream media. It refers to the latest mass die-off in the Earth’s long geologic history, which has suffered cataclysmic events that wiped out vast swaths of the planet’s inhabitants. The fifth and most recent such extinction occurred about 66 million years ago when dinosaurs were obliterated by what is believed to have been an asteroid measuring about 10 kilometers in diameter colliding with the Earth. Evidence of an enormous crater in the Yucatan Peninsula seems to support this theory.
Last year, Duke University biologist Stuart Pimm said the planet is now “on the verge of the sixth extinction,” and the cataclysm is not an asteroid or a microbe or a chain of volcanic eruptions––it’s mankind. Pimm co-authored a study published in the journal Science that concluded that flora and fauna are disappearing at a rate one-thousand times faster than the rise of humanity. Deforestation, habitat fragmentation, poaching, overfishing, climate change and the introduction of invasive species have all led to the current decline in animal species.
The problem is so widespread that Louis Psihoyos, the filmmaker behind the Academy Award-winning documentary “The Cove” has produced a new film on the subject, entitled “Racing Extinction.”
“We’re the only generation left with the time to solve this issue,” Psihoyos told the African Wildlife Foundation.
Now a new study has confirmed that the sixth mass extinction is not only imminent but that humans will indeed have one or two generations to fix the problem.
The study, published this month in the journal Science Advances, analyzed records of animal die-offs in order to deduce whether or not previous reports of a man-made sixth extinction were overblown. Recognizing that earlier estimates “have been criticized for using assumptions that overestimate the severity of the crisis,” the study’s authors used “extremely conservative” assumptions on anthropogenic impacts to the environment that would cause species to vanish.
Estimating that, in a natural scenario, two mammals would go extinct per 10,000 species per century, the scientists compared this “background rate” to the current rate of mammal and vertebrate extinctions. What the researchers found was shocking.
“Even under our assumptions,” they write, “which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 114 times higher than the background rate.”
Since 1900, about 477 vertebrate species have been wiped out. According to the researchers, without human interference, it would have taken between 800 and 10,000 years to lose that many species. The study concludes that the animal kingdom has suffered “an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way.”
Steps can be taken to mitigate this massive die-off, but according to the authors, “that window of opportunity is rapidly closing.”
Because of their essential role in the planet’s ecosystem, animals do not have to completely disappear before things become disastrous.
“People think nothing bad will come from species loss, because scientists can’t predict exactly how many need to go extinct before the world collapses,” Gerardo Ceballos, the lead author of the study and a senior ecological researcher at the National Autonomous University of Mexico told CNN. “The problem is that our environment is like a brick wall. It will hold if you pull individual bricks, but eventually it takes just one to make it suddenly fall apart.”
Individuals can actually make a difference in this regard by changing their own lifestyles. Reducing one’s carbon footprint, boycotting products that are made from threatened or endangered species, and eating less meat can all help to slow the rate of destruction.
“Whatever we decide to do in next 10 to 15 years will decide the future of biodiversity on Earth,” said Anthony Barnosky, a biology professor at Berkeley and co-author of the study.