Scientists have discovered that mating, male blue-lined octopuses will inject a powerful, incapacitating neurotoxin into the hearts of female octopuses — to avoid being eaten by them when the sea deed is done. Females are typically twice the size of males and will commonly chow down on their sexual partners after coitus.

Learn more about the mating of blue-lined octopuses - a treacherous ordeal involving sex, cannibalism, and sedation.