Wednesday, June 8, 2011

Species Extinction Grossly Overstated





It has been obvious that the wild eyed predictions of wholesale extinction were out of kilter for a long time.  This article starts to redress that balance and put some sense into it all.

Besides, refugia do exist and small populations will linger, waiting for an opportunity to jump out into their larger ranges.  It will take generations, but the buffalo is on the way to reintroducing the Buffalo commons in the Great Plains and even in Russia.  We can expect fully restored populations inside of the next few centuries.

Besides all that we will have the ability to use DNA to restore lost creatures inside the next five years or so and I am certain that the process will become immensely popular.  We may not want a particular beast near our farm land, but any decent island will work wonderfully as a convenient restoration refugia.  I actually expect to see the whole of our lost menagerie to be fully recovered and restored from the recent past.

It will be more difficult for the long extinct, but the mammoth and the mastodon are at the top of the list, particularly if they turn out to be useful in the boreal forest.

Species loss far less severe than feared: study

Nobel laureates call for urgent UN action to save the planet
Stockholm (AFP) May 18, 2011 - Some 20 Nobel laureates called Wednesday for world leaders to urgently act to ensure global sustainability, in recommendations handed over to a special UN committee.

In the "Stockholm Memorandum," the Nobel laureates and a number of environmental science experts concluded that "the planet has entered a new geological age, the Anthropocene," or the age of man.

In this era, where the most important changes to the planet are brought on by human actions and not natural phenomena, the memorandum "recommends a suite of urgent and far-reaching actions for decision makers and societies to become active stewards of the planet for future generations."

Nobel Chemistry laureates Mario Molina and Paul Crutzen, who invented the concept of Antropocene, Economics laureate Amarya Sen and Literature winner Nadine Gordimer were among the signatories to the document.

The memorandum was created over the past two days at the Royal Swedish Academy of Sciences in Stockholm, where it on Wednesday was handed over to Finnish President Tarja Halonen, who co-chairs the UN High-level Panel on Global Sustainability.

The panel, which was appointed by UN Secretary-General Ban Ki-moon, will draw up a report in part based on the memorandum suggestions ahead of the UN Conference on Sustainable Development in Rio de Janeiro in 2012.

Among the suggestions proposed Wednesday was the need to "keep global warming below two degrees Celsius, implying a peak in global CO2 emissions no later than 2015."
Global leaders must also recognise that "environmental sustainability is a precondition for poverty eradication, economic development, and social justice," the memorandum said, also calling for the development of "new welfare indicators that address the shortcomings of GDP."

The Nobel laureates and other experts also stressed the need in a world of almost nine billion people to "foster a new agricultural revolution where more food is produced in a sustainable way on current agricultural land."

On the first day of the symposium on Tuesday the Nobel laureates had staged a mock trial against humanity on charges that it was destroying Mother Earth.

 by Staff Writers

Paris (AFP) May 18, 2011



The pace at which humans are driving animal and plant species toward extinction through habitat destruction is at least twice as slow as previously thought, according to a study released Wednesday.

Earth's biodiversity continues to dwindle due to deforestation, climate change, over-exploitation and chemical runoff into rivers and oceans, said the study, published in Nature.

"The evidence is in -- humans really are causing extreme extinction rates," said co-author Stephen Hubbell, a professor of ecology and evolutionary biology at the University of California at Los Angeles.

But key measures of species loss in the 2005 UN Millennium Ecosystem Assessment and the 2007 Intergovernmental Panel on Climate Change (IPCC) report are based on "fundamentally flawed" methods that exaggerate the threat of extinction, the researchers said.

The International Union for the Conservation of Nature (IUCN) "Red List" of endangeredspecies -- likewise a benchmark for policy makers -- is now also subject to review, they said.

"Based on a mathematical proof and empirical data, we show that previous estimates should be divided roughly by 2.5," Hubbell told journalists by phone.

"This is welcome news in that we have bought a little time for saving species. But it is unwelcome news because we have to redo a whole lot of research that was done incorrectly."

Up to now, scientists have asserted that species are currently dying out at 100 to 1,000 times the so-called "background rate," the average pace of extinctions over the history of life on Earth.

UN reports have predicted these rates will accelerate tenfold in the coming centuries.
The new study challenges these estimates. "The method has got to be revised. It is not right," said Hubbell.

How did science get it wrong for so long?

Because it is difficult to directly measure extinction rates, scientists used an indirect approach called a "species-area relationship."

This method starts with the number of species found in a given area and then estimates how that number grows as the area expands.

To figure out how many species will remain when the amount of land decreases due to habitat loss, researchers simply reversed the calculations.

But the study, co-authored by Fangliang He of Sun Yat-sen University in Guangzhou, shows that the area required to remove the entire population is always larger -- usually much larger -- than the area needed to make contact with a species for the first time.

"You can't just turn it around to calculate how many species should be left when the area is reduced," said Hubbell.

That, however, is precisely what scientists have done for nearly three decades, giving rise to a glaring discrepancy between what models predicted and what was observed on the ground or in the sea.

Dire forecasts in the early 1980s said that as many as half of species on Earth would disappear by 2000. "Obviously that didn't happen," Hubbell said.

But rather than question the methods, scientists developed a concept called "extinction debt" to explain the gap.

Species in decline, according to this logic, are doomed to disappear even if it takes decades or longer for the last individuals to die out.

But extinction debt, it turns out, almost certainly does not exist.

"It is kind of shocking" that no one spotted the error earlier, said Hubbell. "What this shows is that many scientists can be led away from the right answer by thinking about the problem in the wrong way."

Human encroachment is the main driver of species extinction. Only 20 percent of forests are still in a wild state, and nearly 40 percent of the planet's ice-free land is now given over to agriculture.

Some three-quarters of all species are thought to live in rain forests, which are disappearing at the rate of about half-a-percent per year.

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