Male blue-lined octopuses immobilize partners with venom before mating In the animal world, survival often involves strategies that are as ingenious as they are unexpected. Female blue-lined octopuses are much larger than the males.

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. At such a critical moment in US history, we need reporters on the ground. Your donation allows us to keep sending journalists to speak to both sides of the story.

Now, researchers studying the octopuses have learned that not only do male blue-lined octopuses use their venom against enemies, but also against members of their own species — cannibalistic females.

"Mating ended when the females regained control of their arms and pushed the males off," the researchers noted.