Photo taken with a mobile phone shows lemurs at Beijing Wildlife Park in Beijing, capital of China, July 12, 2019. (Xinhua/Pang Yuanyuan)

Photo taken with a mobile phone shows a staff member feeding lemurs at Beijing Wildlife Park in Beijing, capital of China, July 12, 2019. (Xinhua/Pang Yuanyuan)

Photo taken with a mobile phone shows a staff member feeding chimpanzee at Beijing Wildlife Park in Beijing, capital of China, July 12, 2019. (Xinhua/Wei Mengjia)

Photo taken with a mobile phone shows a staff member cooling an elephant at Beijing Wildlife Park in Beijing, capital of China, July 12, 2019. (Xinhua/Wei Mengjia)