It's not all love and hugs in the octopus world: Sometimes, these cunning predators turn on each other. Above, you can witness the first video evidence of cannibalism in a common octopus.
In one of the three instances reported in a new study in the Journal of Comparative Psychology, the camera also captured mussels -- a more acceptable delicacy for an octopus to enjoy -- sitting nearby. So the octopus on film wasn't even desperate when it chose to chow down on its smaller comrade.
In two of the clips, the prey are already dead -- and the tips of their tentacles are eaten. But in the second clip shown, the intended meal is actually still alive. The divers disturbed the predatory octopus, scaring it off of its prey.
These larger octopodes are probably just being logical, Live Science reports: For a large enough octopus, snagging a smaller member of the same species gets them more bang for their buck than hunting down a bunch of tiny mussels.