“The evidence is incontrovertible that recent extinction rates are unprecedented in human history and highly unusual in Earth’s history,” the authors write. Species are being wiped off at 53 times greater than normal. Are we humans next?
“Our analysis emphasizes that our global society has started to destroy species of other organisms at an accelerating rate, initiating a mass extinction episode unparalleled for 65 million years. If the currently elevated extinction pace is allowed to continue, humans will soon (in as little as three human lifetimes) be deprived of many biodiversity benefits.”
According to scientists, there have been five mass extinction events on Earth since the beginning of times, the most recent being 65 million years ago when dinosaurs and about half of all species on the planet were completely annihilated.
And if science is not wrong, the Earth is about to enter another phase of mass extinction – triggered by a massive decrease of biodiversity on Earth over the last few centuries.
A new study, published in Science Advances, has revealed that mankind’s population size and growth may be responsible — contributing significantly by increasing loss of habitation. Over-exploitation of Earth’s resources for economic gain has led to a shift in the planet’s climate.
Earlier estimates of extinction rates were criticized for using assumptions that might overestimate their severity, according to the study authors. To avoid this criticism, they say they used “extremely conservative assumptions” to determine whether human activities are, indeed, causing a mass extinction.
Despite using only the conservative numbers, they found that modern extinction rates have risen sharply over the past 200 years, and this has led to various species disappearing up to about 100 times faster than the normal rate between mass extinctions. The figures are frightening to say the least.
They reveal that the total number of vertebrate species that went extinct in the last century would have taken about 800 to 10,000 years to disappear under normal rate. (The study focuses on vertebrae because they are the group for which the most reliable data exists — mammals, birds, and amphibians have had between 88 and 100 percent of their known species evaluated, whereas only 44 percent of reptiles and 38 percent of fish species have been assessed.)
If those losses occurred, they would likely be “effectively permanent,” the authors say, because the world took hundreds of thousands of years at minimum to re-diversify following other extinction events.
“Averting a dramatic decay of biodiversity … is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing,” the authors conclude in their abstract.