Sixth Mass Extinction on Earth Already Underway: Study
Sat Jun 20, 2015 2:5AM
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The world is undergoing a sixth mass extinction of its biodiversity even by using “extremely conservative assumptions,” scientists say.
In an article published in the journal Science Advances on Friday, a team of scientists warned that “an exceptionally rapid loss of biodiversity over the last few centuries” has been taking place, “indicating that a sixth mass extinction is already under way.”
The study reveals that even with highly conservative estimates, species are perishing around 100 times quicker than the normal rate between mass extinctions, known as the background rate.
According to the study, since 1900, mammals, birds, amphibians, reptiles, and fish died 72 times faster than “normal”.
“If it is allowed to continue, life would take many millions of years to recover, and our species itself would likely disappear early on,” said lead author Gerardo Ceballos of the National Autonomous University of Mexico.
Humans’ activities on the surface of the Earth are considered as the main culprit in triggering biodiversity loss. Clearing lands for logging, farming and settlement, introducing invasive species in new habitats, emitting carbon into the atmosphere that drives climate change, ocean acidification and poisoning ecosystems with toxins, and excessive hunting are among the destructive deeds done to nature by our species.
“Avoiding a true sixth mass extinction will require rapid, greatly intensified efforts to conserve already threatened species, and to alleviate pressures on their populations—notably habitat loss, over-exploitation for economic gain, and climate change,” the study further read, warning that this “window of opportunity is rapidly closing.”
The Earth has experienced five mass extinctions so far, the biggest and the most devastating of all occurred at the end of the Permian period some 252 million years ago, known as the Great Dying, claiming the lives of up to 96 percent of all species. But the last, and the most famous of all, happened some 66 million years ago at the end of the Cretaceous period, widely believed to be triggered by an asteroid impact, and killed off all non-avian dinosaurs and most of other species.
presstv.ir
The world is undergoing a sixth mass extinction of its biodiversity even by using “extremely conservative assumptions,” scientists say.
In an article published in the journal Science Advances on Friday, a team of scientists warned that “an exceptionally rapid loss of biodiversity over the last few centuries” has been taking place, “indicating that a sixth mass extinction is already under way.”
The study reveals that even with highly conservative estimates, species are perishing around 100 times quicker than the normal rate between mass extinctions, known as the background rate.
According to the study, since 1900, mammals, birds, amphibians, reptiles, and fish died 72 times faster than “normal”.
“If it is allowed to continue, life would take many millions of years to recover, and our species itself would likely disappear early on,” said lead author Gerardo Ceballos of the National Autonomous University of Mexico.
Humans’ activities on the surface of the Earth are considered as the main culprit in triggering biodiversity loss. Clearing lands for logging, farming and settlement, introducing invasive species in new habitats, emitting carbon into the atmosphere that drives climate change, ocean acidification and poisoning ecosystems with toxins, and excessive hunting are among the destructive deeds done to nature by our species.
“Avoiding a true sixth mass extinction will require rapid, greatly intensified efforts to conserve already threatened species, and to alleviate pressures on their populations—notably habitat loss, over-exploitation for economic gain, and climate change,” the study further read, warning that this “window of opportunity is rapidly closing.”
The Earth has experienced five mass extinctions so far, the biggest and the most devastating of all occurred at the end of the Permian period some 252 million years ago, known as the Great Dying, claiming the lives of up to 96 percent of all species. But the last, and the most famous of all, happened some 66 million years ago at the end of the Cretaceous period, widely believed to be triggered by an asteroid impact, and killed off all non-avian dinosaurs and most of other species.
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