Secrets of the Octopus HydraHD

Octopuses are like aliens on Earth: three hearts, blue blood and the ability to squeeze through a space the size of their eyeballs. But there is so much more to these weird and wonderful animals. Intelligent enough to use tools or transform their bodies to mimic other animals and even communicate with different species, the secrets of the octopus are more extraordinary than we ever imagined.

• octopus
• secrets