Biodiversity projections look grim.

• Author: Porter, Sarah
• Position: Brief Article

One- to two-thirds of all plants, animals, and other species could be lost by the end of the next century if current rates of extinction continue, according to a report presented to the International Botanical Congress in August 1999 by biodiversity expert Peter Raven, director of the Missouri Botanical Garden.

Under current trends, as many as 100,000 of the Earth's estimated 300,000 plant species will disappear or be highly endangered within half a century, largely due to the destruction of habitat. At current levels of destruction, only 5 percent of tropical forests will remain in protected areas within 50 years, says the report, causing the rate of species loss to reach three or four orders of magnitude higher than the natural background extinction rate of about one species each year.

Currently, about 12 percent of plants, 11 percent of birds, and 25 percent of mammal species are extinct or are threatened with extinction according to estimates from the World Conservation Union's (IUCN) "Red List" reports (see "Environmental Intelligence, July/August 1998). And these estimates may be conservative, as scientists have catalogued only 1.6 million of...