Over the past half billion years, there have been at least twenty mass extinctions.
Marine extinctions are uncovered slowly on a global scale, but local disappearances are much more rapidly apparent.
Mass extinctions, says Anthony Barnosky, are geological events in which at least 75% of animal species were wiped out.
"Here we have evidence of local extinctions, replacements and long-distance dispersals, " she explained.
In some places, especially in Haiti, where severe deforestation is added to the mix of problems, extinctions are possible.
The book explains how Earth will change for every degree rise in temperature - from droughts to mass extinctions.
To their surprise they found the assumption that big extinctions take longer to recover from than small did not apply.
Smith says the plant extinctions that have occurred since the first Earth Summit in 1992 have all been entirely avoidable.
We experienced two mass ocean extinctions 55 and 251 million years ago.
Initially, at least, this "man-made" biodiversity will be far too small and slow to compensate for man-made extinctions, but it's worth noting the possibility.
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Two-thirds of the world's polar bear populations could face local extinctions within 45 years due to habitat loss, the National Resources Defense Council says.
"Invasive species are something that is very well addressed by conservation efforts, and there is scope to avoid extinctions and turning species' fortunes around, " he said.
But should the emphasis change if extinctions are our fault?
"Synchronous to within a gnat's eyebrow" according to Professor Paul Renne from the Berkeley Geochronology Centre, who argues that the asteroid clearly played a major role in global extinctions.
The effects of rising global temperatures are widespread and costly: more severe storms, rising seas, species extinctions, and changes in weather patterns that will alter food production and the spread of disease.
The rates of carbon entering the atmosphere in the lead-up to these extinctions are estimated to have been 2.2 and 1 to 2 gigatons of carbon per year respectively, over several thousand years.
Military experts warn us our national security is threatened by massive waves of climate refugees destabilizing countries around the world, and scientists tell us the very web of life is endangered by unprecedented extinctions.
The researchers suggest the evolution of large body sizes among dinosaurs was the result of long exposures to stable environments, and was reset by the mass extinctions that occurred at the end of these periods.
Prof Barnosky and colleagues compared the rates of known species extinctions in mammals, birds and amphibians during the last five centuries with those estimated from the fossil record during the previous Big Five die-outs of the geological past.
If the new EU members do not act on this warning, BirdLife says, "there will be further massive declines or even extinctions of wildlife... especially in those areas as yet relatively untouched by the ravages of intensive farming".
BBC: NEWS | Science/Nature | Farming 'killing Europe's birds'
More than 20 species have been successfully cloned, and there is now talk in some conservation circles of a veritable Jurassic Park-effect becoming essential, as the rate of species extinctions exceeds anything biologists even a generation ago could have imagined.
"Methane hydrate was a key cause of the global warming that led to one of the largest extinctions in the earth's history, " Ryo Matsumoto, a professor at the University of Tokyo who has spent 20 years researching the subject, told Bloomberg in December.
For years, those of us in the realms of social justice, biology, ecosystem integrity, the crises of extinctions and the ever-challenging questions of custodial jurisdiction over the endemic and native seeds that make or break small farmers, particularly in economically stressed nations, has posed unique legal, biocultural and intellectual hurdles, some battered by allegations that many farmers, desperate to hold on, have committed suicide.
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