This truly amazing footage of an octopus was taken by marine biologist Roger Hanlon - and he says it made him scream bloody murder at the time as it seemingly appeared out of thin air.
Hanlon and a team of researchers at the Marine Biological Laboratory in Woods Hole are studying the camouflage ability of cephalopods - and it doesn't get much better than this example.
"The amazing thing is that these animals are colour blind yet they are capable of creating colour-match patterns," he told Science Friday.
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