Findings place the current extinction rate at more than 100 times higher than in periods when Earth was not going through a mass extinction event. Barnosky and an author of the report, which was published Friday.
“You can kind of think of it as guns and bullets”, Barnosky says.
Among them are the California grizzly bear, the Tasmanian tiger, and China’s baiji river dolphin. “Unless we do something radically different soon, we may end up having a big catastrophic collapse of humans, not only animals”. But more than 1,500 still survive in states such as Idaho, Montana and Wyoming.
The study has used a wide array of fossil record to calculate to estimate both the current extinction rate and the background rate.
Even when the researchers only included species that were confirmed extinct, 198 species, the die-off was 22 times the background rate. The list told them that 35 of 5,513 known mammal species have gone extinct since 1900. “In one century, we’re destroying works of art that evolved over millions of years”.
Some scientists have challenged this theory; they believe earlier estimates rested on assumptions that overestimated the crisis.
The study goes on to assert that the timing of this mass extinction makes it most likely human-caused: it’s been happening as human culture has advanced and humans have had a greater impact on the world around us.
“””(The study) shows without any significant doubt that we are now entering the sixth great mass extinction event,” said Paul Ehrlich, senior fellow at the Stanford Woods Institute for the Environment.
The work was divided between the Berkeley and Stanford labs.
That includes switching from fossil fuels to renewable energy sources like wind and solar, producing food more efficiently and limiting population growth.
Specifically, the researchers say the average rate of vertebrate species loss over the last hundred years is 114 times higher than the normal or “background” rate of loss.
The researchers noted that amphibians, which account for 7,300 of the species documented by the IUCN, have been particularly hard-hit.
Now, humans are delivering the coup de grâce, according to the team. To a paleontologist, it means that at least 3 out of every 4 species on Earth disappear in a relatively short period of geologic time (which could be as long as a couple of million years, Barnosky said).
The global Union for Conservation of Nature backs up the alarming news, providing a threat level of 26 percent for mammals and 41 percent for amphibians – Elrich calls those who made it into the statistic “the walking dead“.
The defunct species aren’t the only ones that suffer, Barnosky said. Follow her at Twitter.com/Lisa M. Krieger.
Deforestation was one of the reason cited by the study for the impending “mass extinction event”. In his new book “Dodging Extinction”, he offers these preventive actions: Spread the word that the crisis is real. It also comes six months ahead of a U.N. climate summit in Paris, where President Barack Obama and other world leaders reportedly hope almost 200 nations will agree to reduce their carbon emissions.