An octopus has been spotted changing colour in ink-credible footage from a Welsh beach. Beachgoers captured the rare sight of the curled octopus while looking in rock pools on Menai Bridge beach ...

At the same time, octopuses are as alien as any extraterrestrial you might dream up. For starters, they have three hearts and blue blood. When feeling under threat, they squirt a cloud of ink and ...

Most octopuses have an ink sac as a defense mechanism. The octopus can spew ink into the surrounding water to scare predators away — or befuddle the enemy while they make their getaway.