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Earth enters sixth mass extinction; researchers warn about impending danger

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Earth is entering the sixth mass extinction with humanity too in danger of being wiped off the planet, researchers have warned and with impending danger on all species including humans, experts call for fast action to conserve threatened and endangered species, populations and habitat as the window of opportunity is closing rapidly.

According to a new ew study, published in the journal Science Advances, species are disappearing up to about 100 times faster than the normal rate between mass extinctions, known as the background rate and if this is allowed to continue, life on Earth as we know it will take millions of years to recover, and chances are we humans may also be wiped off the planet quite early.

The research is a collaborative work of a group of scientists including Paul Ehrlich, the Bing Professor of Population Studies in biology and a senior fellow at the Stanford Woods Institute for the Environment and Gerardo Ceballos of the Universidad Autónoma de México, who is also the lead author of the paper.

“[The study] shows without any significant doubt that we are now entering the sixth great mass extinction event,” Ehrlich said.

Though the research doesn’t bring out optimistic vibes in anyone, researchers say that there is a meaningful way forward.

“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’s authors write.

Scientists and experts have already reached a consensus as far as the extinction rates are concerned; however, there are those who have challenged the theory, believing earlier estimates rested on assumptions that overestimated the crisis.

Conservative approach

Using fossil records and extinction counts from a range of records, the researchers compared a highly conservative estimate of current extinctions with a background rate estimate twice as high as those widely used in previous analyses. This way, they brought the two estimates – current extinction rate and average background or going-on-all-the-time extinction rate – as close to each other as possible.

Focusing on vertebrates, the group for which the most reliable modern and fossil data exist, the researchers asked whether even the lowest estimates of the difference between background and contemporary extinction rates still justify the conclusion that people are precipitating “a global spasm of biodiversity loss.” The answer: a definitive yes.

“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,” the researchers write.

To history’s steady drumbeat, a human population growing in numbers, per capita consumption and economic inequity has altered or destroyed natural habitats. The long list of impacts includes:

  • Land clearing for farming, logging and settlement
  • Introduction of invasive species
  • Carbon emissions that drive climate change and ocean acidification
  • Toxins that alter and poison ecosystems

Now, the specter of extinction hangs over about 41 percent of all amphibian species and 26 percent of all mammals, according to the International Union for Conservation of Nature, which maintains an authoritative list of threatened and extinct species.

“There are examples of species all over the world that are essentially the walking dead,” Ehrlich said.

As species disappear, so do crucial ecosystem services such as honeybees’ crop pollination and wetlands’ water purification. At the current rate of species loss, people will lose many biodiversity benefits within three generations, the study’s authors write. “We are sawing off the limb that we are sitting on,” Ehrlich said.