octopuses have elaborate cardiovascular and nervous systems their cardiovascular system includes three hearts two pump blood to the gills and a third moves blood throughout the rest of the body unlike human blood octopus blood is copper based which makes it appear blue the octopus nervous system includes a brain but two-thirds of the octopus's neurons are found throughout its body especially in its arms this means the arms have significant local control and sensory capabilities they may even still reach or grasp after they are severed and their suckers are able to sense chemicals in other words smell or taste octopuses are intelligent some scientists believe octopus intellect can be found in their ability to use tools and exhibit foresight to retain complex memories which helps them navigate mazes and solve puzzles and to use visual cues which helps them differentiate between human individuals octopuses have also been shown to play an activity considered a sign of intelligence [Music] most octopus species only live between one and two years much of this short lifespan has to do with the octopus's reproductive process when octopus is made males may be strangled and eaten by females males are often smaller than females so they become overpowered and sometimes cannibalized once fertilization is complete while females survive the mating process they die after laying their eggs female octopuses guard their eggs for up to eight weeks during this time the female's body self-destructs through cellular suicide until she dies octopus ink is deadly even for the octopus [Music] the ink is a seemingly innocent mixture of mucus and melanin melanin the same dark pigment found in skin hair and eyes also happens to contain the chemical compound tyrosinase which can impair a predator's sight taste and smell octopuses and other cephalopods may use their ink to distract confuse and paralyze their predators this mucus mixture may even block a fish's gills causing the fish to suffocate i