Male Blue-Lined Octopuses Use Venom to Prevent Cannibalism During Mating

Researchers reveal that male blue-lined octopuses sedate larger female mates with tetrodotoxin to avoid being eaten post-copulation.

Male blue-lined octopuses inject females with the neurotoxin tetrodotoxin during mating to immobilize them and avoid post-copulation cannibalism.
The venom, produced by symbiotic bacteria, is delivered via a precise bite to the female's aorta, temporarily paralyzing her for up to an hour.
Despite the immobilization, female octopuses survive the process, showing resistance to the toxin and later laying eggs within 3 to 29 days.
Male octopuses have significantly larger venom glands than females, likely an evolutionary adaptation to their mating strategy.
This behavior highlights an evolutionary arms race between sexes, as females grow larger and more aggressive while males develop strategies to ensure reproductive success.