Mass Extinction Underway - Majority of Biologists are convinced:






A majority of the nation's biologists are convinced that a "mass extinction" of plants and animals is underway that poses a major threat to humans in the next century, yet most Americans are only dimly aware of the problem, a poll says.

The rapid disappearance of species was ranked as one of the planet's gravest environmental worries, surpassing pollution, global warming and the thinning of the ozone layer, according to the survey of 400 scientists commissioned by New York's American Museum of Natural History.

The poll's release yesterday comes on the heels of a groundbreaking study of plant diversity that concluded than at least one in eight known plant species is threatened with extinction. Although scientists are divided over the specific numbers, many believe that the rate of loss is greater now than at any time in history.

"The speed at which species are being lost is much faster than any we've seen in the past -- including those [extinctions] related to meteor collisions," said Daniel Simberloff, a University of Tennessee ecologist and prominent expert in biological diversity who participated in the museum's survey. [Note: the last mass extinction caused by a meteor collision was that of the dinosaurs, 65 million years ago.]

Most of his peers apparently agree. Nearly seven out of 10 of the biologists polled said they believed a "mass extinction" was underway, and an equal number predicted that up to one-fifth of all living species could disappear within 30 years. Nearly all attributed the losses to human activity, especially the destruction of plant and animal habitats.

Among the dissenters, some argue that there is not yet enough data to support the view that a mass extinction is occurring. Many of the estimates of species loss are extrapolations based on the global destruction of rain forests and other rich habitats.

Among non-scientists, meanwhile, the subject appears to have made relatively little impression. Sixty percent of the laymen polled professed little or no familiarity with the concept of biological diversity, and barely half ranked species loss as a "major threat."

The scientists interviewed in the Louis Harris poll were members of the Washington-based American Institute of Biological Sciences, a professional society of more than 5,000 scientists.

Acknowledgements: Washington Post

Mass extinctions