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Earth is entering its next mass extinction stage, according to many scientists. They say with confidence, three-quarters of all species on earth could disappear in the next couple centuries. The scientists also state that we as humans are the culprits, at least to a significant degree.
A study published in Monday’s Proceedings of the National Academy of Sciences publication states humans are inflicting a "biological annihilation" on the earth and its natural elements. Ecology professor Gerardo Ceballos at the Universidad Nacional Autónoma de México along with his co-authors which includes well-known Stanford University biologist Paul Ehrlich documented brand new evidence how populations of species we thought were common are suffering in unseen ways.
Ceballos said, "What is at stake is really the state of humanity."
Their key findings: Nearly one-third of the 27,600 land-based mammal, bird, amphibian and reptile species studied are shrinking in terms of numbers and range of territory. The researchers call this an "extremely high degree of population decay."
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One hundred and seventy-seven mammal species were looked over by the research scientists were found to have lost 30 percent of their territory from 1900 to 2015. Also, over 40 percent "experienced severe population declines," meaning they lost at least 80% of their geographic range during that time.
If you study this crisis not only in terms of species which are on the brink or extinction as well as ones whose populations are shrinking, this allows you to see "Earth's sixth mass extinction is more severe" and pressing than it was thought to be, say the authors. They also state say a major extinction event is "ongoing."
Anthony Barnosky, executive director of the Jasper Ridge Biological Preserve at Stanford University says, "It's the most comprehensive study of this sort to date that I'm aware of." Barnosky was not involved in the study but he did say the studies value it makes visible a phenomenon typically unseen by scientists and the public: that even populations of relatively common species are crashing. He said "We've got this stuff going on that we can't really see because we're not constantly counting numbers of individuals, but when you realize that we've wiped out 50% of the Earth's wildlife in the last 40 years, it doesn't take complicated math to figure out that, if we keep cutting by half every 40 years, pretty soon there's going to be nothing left."
Chair of Conservation Ecology at Duke University in North Carolina, Stuart Pimm summarized the crisis in this way: "When I look out over the woods that constitute my view from my window here, I know we no longer have wolves or panthers or black bears wandering around. We have eliminated a lot of species from a lot of areas. So we no longer have a functional set of species across large parts of the planet." Pimm says it’s important not to forget this however, it’s also important not to allow the report to come off as an overstatement stating and the research methodology does not have the level of granularity needed to be particularly useful for conservationists. "The value of the Ceballos paper is a sense of the problem. But given there's a problem, what the bloody hell are we going to do about it?" Pimm also said, "What good mapping does is to tell you where you need to act."
Ceballos and his team showed that entire populations of other plants and animals are crashing, even if they're not yet on the brink of extinction, in which some of these are well-known like the African elephant. Barnosky says "On the one hand, you can say, 'All right, we still have around 400,000 elephants in Africa, and that seems like a really big number,' " he said. "But then, if you step back, that's cut by more than half of what their populations were in the early part of last century. At that time there were well over 1 million elephants.
According to Barnosky if the rampant pace from the last decade’s elephant deaths is kept up there would be no more wild elephants in Africa in 20 years.
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Ceballos says jaguars and barn swallows are two prime examples with somewhat common statistics in numbers and which are in rapid decline. He says population crashes of this nature can lead to relative fast extinctions at 100 times [or more] of what is considered to be a normal rate.
It should be noted that there is a debate about whether or not the planets’ sixth mass extinction event is above the horizon or that the process is already underway. There is no debate over whether or not humans are much to blame for this, and the reasons are evident and widely understood. Burning Fossil fuels, forest destruction, land consumption and a rising population, to name a few while the black market is being flooded with elephants, pangolins, giraffes, and rhinos.
These combined elements are contributing to rapid declines for both land and ocean dwellers. However urgent, Ceballos explains "The good news is, we still have time," he said. "These results show it is time to act. The window of opportunity is small, but we can still do something to save species and populations."