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The moment an octopus camouflaged itself against a coral reef to become invisible has been revealed in an amazing video.

The footage shows what appears to be just a lifeless reef area.

But as the diver approaches, the octopus suddenly jumps into view as it deactivates its 'cloaking mechanism'.

Seeing is believing: It might be hard to believe, but there is actually an octopus hidden in this video. The still is from a video that shows the cephalopod changing the tone and texture of its skin to unmatch from its surroundings and reveal itself to a diver

The footage was captured by Jonathan Gordon in the Caribbean.

'I dove down to have a look at the shell that you can see just under where the octopus appears and as I approached the octopus came out of hiding,' he said.

'I had literally no idea he was there until I was about a metre away.'

Octopuses are one of a few marine creatures that can camouflage themselves underwater; others include the cuttlefish and squid.

The cephalopod - a mollusc with its arms attached to its head - can not only change the tone of its skin to match its surroundings, but also its texture to blend in.

Incredibly, they are able to do all this despite being colour blind. Scientists still aren't quite sure how they know what the colour of the object their hiding against is.

It may be they are able to detect slight contrasts in colours by filtering it in their body, or proteins in their skin and eyes known as opsins may be the cause of its amazing ability.

Perhaps, still, it is just a case of natural selection - it might be that some have evolved the ability to match certain colours, and thus are able to survive.

Octopus shocks diver with its amazing camouflage skills

As the video progresses, the octopus starts to become visible. 'I dove down to have a look at the shell that you can see just under where the octopus appears and as I approached the octopus came out of hiding,' said Jonathan Gordon, the diver who captured the footage

Octopuses camouflage themselves to hide from predators, and when they reveal themselves they can increase their size (shown) to make them look even more intimidating

To change the colour of its skin, an octopus has thousands of colour-changing cells known as chromatophores beneath the surface of its skin.

These contain an elastic sac full of pigment, the colour of which can be altered.

The sacs can also be expanded or contracted by an array of nerves, and when it is expanded the colours become more visible.

By controlling the size of projections on its skin known as papillae, an octopus can also change the texture of its skin from bumps to spikes.

This means they can not only match the colour of a reef, but its texture as well.

They attach themselves to solid objects to camouflage and, if discovered, they 'puff' themselves up in size to make them look more intimidating. 

One of the reasons octopuses camouflage themselves is to hide from predators. If threatened, they can also spray ink in the face of their attacker before making a quick getaway.