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Earth 'entering new extinction phase' - US study
From the section Science & Environment
The dried out sea bed of the Soyang River in Chuncheon, Gangwon Province, northeastern South Korea, 16 June 2015
See link: http://www.bbc.com/news/science-environment-33209548
Climate change and deforestation are among the reasons we may be facing an extinction event.
The Earth has entered a new period of extinction, a study by three US universities has concluded, and humans could be among the first casualties.
The report, led by the universities of Stanford, Princeton and Berkeley, said vertebrates were disappearing at a rate 114 times faster than normal.
The findings echo those in a report published by Duke University last year. One of the new study's authors said: "We are now entering the sixth great mass extinction event."
The last such event was 65 million years ago, when dinosaurs were wiped out, in all likelihood by a large meteor hitting Earth.
"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 the lead author, Gerardo Ceballos.
Pollination by bees could disappear within three generations, the report warns.
The scientists looked at historic rates of extinction for vertebrates - animals with backbones - by assessing fossil records. They found that the current extinction rate was more than 100 times higher than in periods when Earth was not going through a mass extinction event.
Since 1900, the report says, more than 400 more vertebrates had disappeared. Such a loss would normally be seen over a period of
up to 10,000 years, the scientists say.
The study - published in the Science Advances journal - cites causes such as climate change, pollution and deforestation.
Given the knock-on effect of ecosystems being destroyed, the report says benefits such as pollination by bees could be lost within three human generations.
Extinction may be more gradual than when the dinosaurs died, the report says.
Stanford University professor Paul Ehrlich said: "There are examples of species all over the world that are essentially the walking dead.
"We are sawing off the limb that we are sitting on."
The International Union for Conservation of Nature (IUCN) says at least 50 animals move closer to extinction every year.
Around 41% of all amphibians and 25% of mammals are threatened with extinction, it says.
Most at risk: the lemur
According to the IUCN, the lemur faces a real struggle to avoid extinction in the wild in the coming years. The group says that 94%
of all lemurs are under threat, with more than a fifth of all lemur species classed as "critically endangered".As well as seeing their habitat in Madagascar destroyed by illegal logging, lemurs are also regularly hunted for their meat, the IUCN says.
Last year, a report by Stuart Pimm, a biologist and extinction expert at Duke University in North Carolina, also warned mankind was entering a sixth mass extinction event.
But Mr Pimm's report said the current rate of extinction was more than 1,000 times faster than in the past, not 114, as the new report claims.
The new report's authors said it was still possible to avoid a "dramatic decay of biodiversity" through intensive conservation, but that rapid action was needed.
Posted : June 20, 2015 7:04 am
Topic starter
The Sixth Great Mass Extinction Is Coming: How Do We Stop It?
by Steve Williams
June 23, 2015
Posted : June 24, 2015 1:16 pm
Topic starter
A Sixth Mass Extinction Has Begun. Will Your Favorite Wild Animal Die Out?
Diane MacEachern
Jun 26, 2015
Thanks to several “overs” – as in overfishing, overdevelopment, overheating (aka, climate change), and overuse of natural resources – the planet is experiencing a “sixth great extinction” of animal species. Everything from the Yangtze dolphin to the Costa Rica golden toad to backyard songbirds are at risk. Extinction rates for mammals, reptiles, amphibians and fish are anywhere from 10 times to more than 100 times higher than normal. The impact could be worse than the last great animal die-out – the one that occurred 65 million years ago, when the dinosaurs went extinct.
These are the findings of a study titled “Accelerated modern human-induced species losses: Entering the sixth mass extinction,” which was conducted by scientists from the National Autonomous University of Mexico.
“The evidence is incontrovertible,” they said, “that recent extinction rates are unprecedented in human history and highly unusual in Earth’s history.”
Alarmingly, they also say that their projections about the number of animals actually expected to go extinct is “very conservative.”
“Our calculations very likely underestimate the severity of the extinction crisis,” they note. They acknowledge that “biologists cannot say precisely how many species there are, or exactly how many have gone extinct” in any particular time period. However, “we can confidently conclude that modern extinction rates are exceptionally high, that they are increasing.
“A mass extinction is under way – the sixth of its kind in Earth’s 4.5 billion years of history.”
Apart from having an attachment to an animal you might find cute or endearing, you should be concerned about this loss of the variety of animal life scientists call “biodiversity” because of the impact it can have on the availability of your favorite foods and even clean water. Loss of biodiversity affects crop pollination and water purification, as well as the survival of the food chain as we know it.
It also represents the loss of “humanity’s beautiful, fascinating, and culturally important living companions” – in other words, the creatures that make all of us realize that we share the planet with much more than human beings.
“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,” warns the report.
Avoiding a true sixth mass extinction will require rapid, greatly intensified efforts to conserve already threatened specieis and to alleviate pressures on their populations – notably habitat loss, overexploitation for economic gain, and climate change.
“Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing,” say the study’s authors.
How Can You Help?
1) Consume less, swap and trade more. The “sharing economy” is one approach that offers a positive solution to humanity’s problem of over-consumption. Rather than buy more new stuff, which necessarily requires the use of more natural resources, do your part to share what you have, swap with friends and neighbors, recycle and reuse, and avoid the temptation to buy the latest, greatest, “shiny new things.” All these things require energy and water and other natural resources that the web of life depends on. Cut back on consumption to help keep animal extinction at bay.
2) Shift to renewable, non-polluting, non-extractive sources of energy. Burning fossil fuels releases carbon dioxide into the atmosphere, which creates an insulating gaseous blanket over the earth that traps heat and raises on-the-ground temperatures. This global warming has given rise to climate change, and it’s happened so quickly that many animals have not been able to evolve and adapt. Plus, mining for coal and drilling for oil and natural gas pollute the air and water, sometimes with disastrous consequences. Just a thimbleful of oil can contaminate a gallon of water; imagine the impact on the animals that live in and around an ocean or river or bay when oil spills occur, and they do, hundreds of times a year. Energy from the sun and wind are renewable and non-polluting and do not contaminate the land on which they sit. Plus, every year, solar and wind are becoming more affordable. Contact your utility company to see what options they offer for you to get your energy from clean energy sources.
3) Eat more vegetables. Yes, you’ll be healthier. But you’ll also help protect animal habitat. Overfishing is decimating the world’s fish stocks, while clearcutting rainforests to raise more livestock is obliterating the habitat that millions of birds, mammals, reptiles and insects call home. Eat organically while you’re at it, to reduce the use of indiscriminate pesticides that take their toll on bees, butterflies and beneficial bugs. Better yet, try growing more of your own food.
4) Protect wilderness on land and sea. Not nearly enough land is protected as wilderness, which would put it off limits to drilling, mining and other forms of development. And we need more marine sanctuaries to safeguard expanses of the oceans to allow fish and sea mammals to rebuild their populations. Urge your elected officials in the U.S. Congress and statehouses to pass wilderness legislation, and support non-profit organizations advocating on behalf of wilderness protection in America and around the world.
5) Vote. All of us can only do so much on our own. It is absolutely critical that we embrace our role as citizens and vote for local, state and national leaders who value life on Earth in all its varied and diverse forms. The politicians sitting in state houses and on Capitol Hill have the power to pass laws that could slow and even stop the sixth mass extinction from taking hold. But they’ll only do the right thing if their constituents give them the courage to do so. Each and every one of us must vote for leaders who understand what is at stake. Our future – and the future of the animals we love – depends on it.
Posted : June 27, 2015 11:50 am
