Published on June 22nd, 2015 | by Aisha Abdelhamid
Sixth Mass Extinction Has Arrived, Confirms Stanford
Declaring that the sixth mass extinction has arrived, Stanford biologist Paul Ehrlich confirms that species are disappearing off the face of Earth faster now than at any time since the mass extinction of dinosaurs.
Calling for “fast action to conserve threatened species, populations and habitat before the window of opportunity closes,” Ehrlich and his team of researchers definitively conclude that humans are “precipitating a global spasm of biodiversity loss.”
Entering The Sixth Mass Extinction Without A Doubt
Stanford biologist Paul Ehrlich, the Bing Professor of Population Studies in biology and a senior fellow at the Stanford Woods Institute for the Environment, and his co-authors report that there is no longer any doubt: We are entering the sixth mass extinction, and it is threatening the very existence of humanity.
Published in the journal Science Advances, the new report states that, even with extremely conservative estimates, “species are disappearing up to about 100 times faster than the normal rate between mass extinctions, known as the background rate.”
Co-author Gerardo Ceballos of the Universidad Autónoma de México stated, “If it is allowed to continue, life would take many millions of years to recover, and our species itself would likely disappear early on.”
The Causes & Consequences of the Sixth Mass Extinction
With extensive work on extinction stretching back to his 1981 book, Extinction: The Causes and Consequences of the Disappearance of Species, Ehrlich is also well-known for his works on the human population. Tying his extensive work on extinction to relationships with such factors as coevolution, racial, gender, and economic justice, and on nuclear winter, Ehrlich is identifying significant components to wildlife depopulation and species loss.
Although some scientists have challenged the sixth mass extinction theory as an overestimation, there is general consensus among scientists today that extinction rates have reached unparalleled levels since the time of the dinosaur’s demise around 66 million years ago.
Estimating the Extent of Extinction
In this new study, Ehrlich and his team of researchers set out to determine if the current rate of extinction is significantly different from the rate of extinction that is “going on all the time,” known as the background rate of extinction. Using a range of fossil records and extinction counts, the scientists compared “a highly conservative estimate of current extinctions” with a background rate estimate “twice as high as those widely used in previous analyses.”
In this way, ruling out any possibility of overestimation, the scientists then narrowed their research to vertebrates, the group for which the most reliable modern and fossil data exists. Writing in the new study, the researchers state, “We emphasize that our calculations very likely underestimate the severity of the extinction crisis, because our aim was to place a realistic lower bound on humanity’s impact on biodiversity.”
Nevertheless, the unavoidable answer was clear from the study. The scientists asked whether even the lowest estimates of the difference between background extinction rates and today’s extinction rates still arrive at the conclusion that humans “are precipitating a global spasm of biodiversity loss.” The answer was a definitive “Yes.” Unequivocally, the scientists report, we have entered the sixth mass extinction event on Earth.
A Global Spasm of Biodiversity Loss
Dr. Paul Ehrlich and his team included Anthony D. Barnosky of the University of California at Berkeley, Andrés García of Universidad Autónoma de México, Todd M. Palmer of the University of Florida, and Robert M. Pringle of Princeton University. They reported that, at the current rate of species loss, people will lose many biodiversity benefits within three generations. “We are sawing off the limb that we are sitting on,” said Ehrlich.
As human population has steadily increased in numbers throughout the course of history, untold numbers of acres of natural habitat have steadily declined and disappeared. With a direct relationship tied to human per capita consumption and staggering economic inequality, this dramatic decline in global biodiversity has come as a result of many factors. Ehrlich and his team include the following list as the most significant factors leading to the sixth mass extinction:
● Land clearing for farming.
● logging and settlement.
● Introduction of invasive species.
● Carbon emissions that drive global warming and ocean acidification.
● Toxins that alter and poison ecosystems.
Crucial ecosystem services disappear, as well, with the extinction of species. For example, crop pollination provided by honeybees, and water purification provided by wetlands. Maintaining an official list of threatened and extinct species, the International Union for Conservation of Nature (IUCN) reports that ecosystem degradation has now put around 26 percent of all mammals, and 41 percent of all amphibian species in critical danger of extinction.
Ehrlich pointed out, “There are examples of species all over the world that are essentially the walking dead.”
Greatly Intensified Conservation Efforts Are Required
Hoping that their work will positively support conservation efforts, the scientists strongly advocate for maintenance of ecosystem services and more widespread support through public policy.
According to Ehrlich and his colleagues, “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.”