No joy in discoveries of new mammal species -- only a warning for humanity, Paul Ehrlich says

In the era of global warming, when many scientists say we are experiencing a human-caused mass extinction to rival the one that killed off the dinosaurs, one might think that the discovery of a host of new species would be cause for joy. Not entirely so, says Paul Ehrlich, co-author of an analysis of the 408 new mammalian species discovered since 1993.

"What this paper really talks about is how little we actually know about our natural capital and how little we know about the services that flow from it," said Paul Ehrlich, the Bing Professor of Population Studies at Stanford.

"I think what most people miss is that the human economy is a wholly owned subsidiary of the economy of nature, which supplies us from our natural capital a steady flow of income that we can't do without," Ehrlich said. "And that income is in the form of what are called 'ecosystem services'-keeping carbon dioxide out of the atmosphere, supplying fresh water, preventing floods, protecting our crops from pests and pollinating many of them, recycling the nutrients that are essential to agriculture and forestry, and on and on."

Ehrlich conducted the analysis with Gerardo Ceballos, a professor of biology at the National University of Mexico. They are co-authors of a paper describing the work, scheduled to be published Monday, Feb. 9, in the online early edition of the Proceedings of the National Academy of Sciences.

The 408 newly discovered species amount to approximately 10 percent of the known species of mammals. As a group, mammals have been very well studied, Ehrlich said, and their size makes them relatively easy to spot compared to insects or microbes. It is not that surprising that multitudes of new insect species are still being discovered, or that new extremophile species are found in hydrothermal vents on the ocean floor, he said. But the new mammals include a small antelope weighing approximately 200 pounds and surprisingly high numbers of primates, more than would be expected if the discoveries were randomly distributed across higher taxonomic groups.

"Our analysis indicates how much more varied biodiversity is than we thought and how much bigger our conservation problems are if we're going to maintain the life-support services that we need from biodiversity," Ehrlich said.

Among those ecosystem services is disease control.

"There's an important set of diseases called hantaviruses that infects human beings and quite frequently kills them. And it turns out that if you reduce the diversity of the different species of rodents, say, in a forest, the rodents that carry hantaviruses can become more common. And the results for human beings are more death and disease," Ehrlich said. "So by reducing the diversity of mouse-like creatures in a forest, you can make that forest more dangerous for people."

Many of the newly discovered species have small populations or limited geographic ranges, making them particularly vulnerable to extinction.

"The rarer of the species and the smaller of the populations often disappear without us even knowing that they are going," Ehrlich said.

Although not every species that goes extinct plays a crucial role in controlling diseases like hantaviruses, that doesn't necessarily mean we can do without them.

Ehrlich said the answer to the question, "What difference does it make if we put a strip mall in here and this little fly goes extinct, or this little mouse goes extinct?" lies in the rivet-popper hypothesis, which he and his wife and colleague, Anne Ehrlich, a senior research scientist in the Department of Biology at Stanford, developed in the 1980s.

An airplane wing has a certain amount of redundancy in its design, as does much of nature. So you can pop off some of the rivets and the wing will still hold together and the plane will still fly. But at some point, you'll have removed one too many rivets and the plane will crash.

"Even though you don't know the value of each rivet, you know it's nuttier than hell to keep removing them," Ehrlich said. "There is some redundancy, but we don't know how much. And facing serious climate disruption, humanity is going to need more redundancy in the little rivets, the species and populations that run the world.

"We are facing for the first time the collapse of a global civilization," he said. "You have to reduce the scale of the human enterprise to having a chance at preventing that."

Ehrlich said that continually creating more mouths to feed will only chew up more of Earth's natural capital.

"The economy of nature is what allows us to have a human economy. If we let the infrastructure of nature go down the drain, then we just can't make up for it with human infrastructure," he added. "It just can't be done."

Source: Stanford University

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Feb 09, 2009
FTA: "I think what most people miss is that the human economy is a wholly owned subsidiary of the economy of nature, which supplies us from our natural capital a steady flow of income that we can't do without,"

And we will manage that economy for your ignorant serfs :)

Every year it becomes more and more blatant what these guys are governmental management of your M O N E Y.

Feb 09, 2009
Starting in the 60's, Paul Ehrlich and his wife Anne have made many prognostications but have never predicted anything correctly. Why should we start paying attention to their hot air now?

Feb 10, 2009
People in general will never truly care about things they can't see/hear/feel immediately. They don't care about mass extinctions because they don't feel the effects at all (yet). We suck i suppose.

Feb 10, 2009
If humanity behaves like hamsters who overshit their cages and drown in their own excreta, then humanity deserves the breakdown and collapse that will result. Human degeneracy is the result of ignorance outpacing intelligence. Any nation or race of people that loses its intellect in favor of consumption and entertainment will collapse back into beastiality and violence and eventually be supplanted by a more intelligent group.

When I see the blank stares and stupid grins of a people in the euphoria preceeding collapse, I see the culmination of every absurd religion, every childish fantasy of self-delusion, and every self-destructive behavior that was allowed to metasticize over the last 200 years.

The West has completely betrayed its intellectual progenitors, and after centuries of vile retrograde has become imbecile and juvenile. Instead of growing into mature, free, post-enlightment sentience we have reverted to overfed, dominated, spoiled children unable to comprehend the duties of an adult species.

Instead of rationally conserving this planet and learning the keys of world-management that is the basic prerequisite for a species to advance in the universe, we dwindle in post-industrial mental illness and destroy our minds with pleasures and illusions.

The West may ultimately be a case of a civilization that failed to flourish, trading its immense promise and progress for the vanity of apocalyptic religions and totalitarian self-immolation. Good riddance, what a miserable culture in which to have developed sentient intellect.

Feb 11, 2009
I am afraid we will ruin this planet. Too much humans to feed. We should aim for a steady population of 2-4 billions and a sustainable economy but there is no one at the top who could steer humanity in the right direction.

We may learn to control ourselves after the first global disaster caused by our negligence wipes out significant portion of Earth population, then again it's far from certain.

It is even possible that the first truly sustainable economy on Earth will not be due to humans at all, Nature produced one intelligent animal, given time she may produce more, or she may decide intelligence is not the way to go after all and develop something else.

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