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In the clip, an unidentified tourist shows off his latest discovery, an adorable little octopus covered in bright blue stripes. It’s the kind of thing that vacation videos are made for ...

dive into the story of the dumbo octopus, the small octopus with big ears that lives four miles below the sea. Then, read about the blue-ringed octopus, one of the deadliest creatures on the planet.

Finally, why do octopuses have blue blood? Are you still wondering why octopus blood is blue and what the three hearts do? Well, the blue blood is because the protein, haemocyanin, which carries ...