Male blue-lined octopuses inject a powerful neurotoxin into the hearts of females before mating to avoid being eaten, according to a new study.

Animals have evolved many different ways of protecting themselves, from prickly quills and razor-sharp teeth to clever camouflage and sturdy shells. Now, scientists have discovered a surprising new technique that appears to be a defense mechanism: Some male octopuses use venom to avoid being eaten by their female mates.

The blue-lined octopus is a creature of paradox. It’s a small yet deadly creature with enough paralyzing venom to kill a man. It’s also got a dazzling colorful display but a voracious appetite. To top it all off,

Male blue-lined octopuses inject females with venom to paralyse them before mating and avoid being eaten after sex.

Male blue-lined octopi (Hapalochlaena fasciata) have been found to use venom on their sexual partners, as well as for the usual reasons of defense against predators and subduing prey. Killing the females would be counterproductive,

While unfortunate for the males, becoming a post-sex meal offers the females vital nutrients needed to sustain themselves and their soon-to-be hundreds of gestating offspring. This practice is especially common in animals exhibiting female sexual dimorphism,

Scientists have found that male blue-lined octopuses inject venom and paralyse females during sex to avoid being killed and cannibalised by their much larger partners. The male octopus of this species precisely injects a dose of its deadly tetrodotoxin venom into the females to immobilise them during copulation,