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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 ...

Over 100 different species of shark are found in South African waters ... By doing so he worked out how to track a hunting octopus and so Blue Planet II cameraman, Roger Horrocks, and assistant ...

There are nearly 30 species of shark found in UK waters, but the blue shark is certainly one of the most impressive. With the white underbelly contrasting with its cobalt blue upper body ...

The bull shark (Carcharhinus leucas ... and invertebrates such as squid, cuttlefish, and octopus. Blue sharks are also known ...