KEEPING THEIR EYES OUT: Trekking into the remote reaches of the Himalayas, researchers have relied on knowledge from locals to help them find new species over the last ten years.
S. MILIVOJE KRVAVAC/WWF NEPAL

Deep in the eastern Himalayas, where two continental plates and four countries converge, a treasure trove of new species has kept scientists on the lookout for the past decade. A recent report, assembled by the World Wildlife Fund International (WWF) based in Washington, D.C., gathered the fruits of these labors—completed by various organizations—and lists the 353 new plant and animal species that years of rugged research have now brought to the wider world's attention.

From the soaring, 8,000-meter mountain peaks of Tibet down through deep gorges and into lowlands of dense, sea-level rainforests in Assam, the eastern Himalayas offer a wealth of species in a range of distinct biomes.

The extreme terrain has kept many of these species hidden from scientific observation for centuries. "Forests are so thick you have to rely on the knowledge of local hunters or people," says Jon Miceler, director of the WWF's Eastern Himalayas Program. "A huge amount [of research] is done through asking people what's out there."

The remote area has yielded some remarkable discoveries. The 2005 description of a new primate, the Arunachal macaque, stunned researchers, who hadn't catalogued a new primate in more than a century.

Slide Show: New Species Discovered in the Himalayas

Miceler and others were also amazed by the report of the tiny leaf deer, which is just a fraction of the size of a North American white-tailed deer. "It's almost something out of science fiction," Miceler says. "You can hold this thing with two hands." That is, if you can find it. The rare photo was only captured after multiple treks into the dense forest. To locate the small animal, researchers got help from locals, some of whom even had skulls of the deer as trophies.

George Amato, who helped describe the leaf deer—and is now director of the Sackler Institute of Comparative Genomics at the American Museum of Natural History in New York City—notes that the late 1990s saw a rush of interest to discover and name new species in remote regions like this. Although many announcements were based on unsubstantiated observations, genetic analysis has helped researchers sort the novel from the nonsensical.