Study finds nearly half the Earth is still wilderness.

• Author: Runyan, Curtis
• Position: Environmental Intelligence

Despite a century of mounting environmental threats, 46 percent of the Earth's land area remains largely intact wilderness, according to a new report by Washington, D.C.-based Conservation International (CI). The comprehensive study--a collaboration of more than 200 scientists from around the world--found that 68 million square kilometers of land met "wilderness" criteria, meaning that they have at least 70 percent of their original vegetation, contain fewer than five people per square kilometer outside urban areas, and have not been reduced to fragments of less than 10,000 square kilometers.

"These areas represent a land mass equivalent to the six largest countries on Earth combined--Russia, Canada, China, the United States, Brazil, and Australia--but have within them the population of only three large cities, a truly remarkable finding," said co-author Russell Mittermeier, president of CI The 37 wilderness areas identified by the report are home to just 144 million people (excluding urban centers)--just 2.4 percent of the world's population.

The "half-the-Earth" finding could be somewhat misleading, insofar as more than one-third of the wilderness is Antarctic ice or Arctic tundra, and only 5 of the 37 areas are conservation-priority areas--meaning that they each contain more than 1,500 endemic species and harbor a high concentration of biodiversity. The five priority areas--each larger than 750,000 square kilometers--are Amazonia, New Guinea, the North American deserts, the Congo...