Never enough sleep

Tuesday marks the World Sleep Day. But it seems that beyond people, some animals never get enough sleep either. A series of photos taken between 2013 and 2017 show cute sleeping positions of animals at Hangzhou Zoo and Hangzhou Safari Park in east China's Zhejiang Province. The photo shows a panda sleeping in a tree. [Photo: VCG]

The photo shows a pair of lions snuggling up to each other while sleeping. [Photo: VCG]

The photo shows two chimpanzees hugging each other while sleeping in the sun. [Photo: VCG]

The photo shows two tigers sleeping head-to-head. [Photo: VCG]