Shiny jellyfish, color-changing frogfish and a crab which gets itself a home in an empty shell – all these creatures can be found underwater off south China's Hainan island, which is known for its beautiful beaches, clean water and rich biodiversity. Each species has its own unique traits and adaptations that suit their own living strategy. Check out the video to see how many animals you can recognize.

For full episode

Underwater Series Ep. 1: The jelly that dances in darkness

Underwater Series Ep. 2: Warm sunshine nurtures ocean 'rainforest'

(Cover image a video screenshot; video by the CGTN Nature film crew.)

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