Until the 1980s people roamed the mountains of Shennongjia in central China hunting monkeys for their meat and fur.
Poor farmers were still clearing vast areas of trees, and as their environment collapsed around them, so did the local population of golden snubbed-nosed monkeys, dropping below 500 in the wild.
This was the situation when new graduate Yang Jingyuan arrived in 1991, still in his early 20s.
"The monkeys' home was being destroyed by logging so their numbers were going down fast," he says. "Now it's being protected, and the monkey figures are really improving."
These days Professor Yang is the director of the Shennongjia National Park Scientific Research Institute and probably no one knows this species better than he does.
