Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
A baby golden monkey is protected by adult golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province, April 28, 2016. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows a golden monkey at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
A baby golden monkey plays a camera at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province, April 28, 2016. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
A newly-born golden monkey stays in the hug of its mother at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province, April 28, 2016. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
A baby golden monkey is protected by adult golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province, April 28, 2016. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
A baby golden monkey plays with an adult golden monkey at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province, April 28, 2016. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua
Photo taken on April 28, 2016 shows golden monkeys at the Dalongtan Golden Monkey Research Base in Shennongjia, central China's Hubei Province. Four golden monkeys were born in April this year at the Dalongtan Golden Monkey Research Base. The number of golden monkeys in Shennongjia has doubled since the 1980s. Photo: Xinhua