August 12, 2008—Numbers of the black-and-white ruffed lemur (Varecia variegata)—which, like all lemur species, is found only on the African island of Madagascar—have dwindled as a result of predation and habitat loss.

Last week the International Union for Conservation of Nature (IUCN) added several species and subspecies of primates, including the ruffed lemur, to the "critically endangered" category in its Red List of Threatened Species.

The additions were made as part of a study by hundreds of experts that suggests half of the world's apes, monkeys, and other primates are in danger of extinction.

• More Photos in the News
• Today's Top 15 Most Popular Stories
• Free Email Newsletter: "Focus on Photography"