Male octopus has ‘sex arm’ that can mate in the dark

Scientists found that the male’s hectocotylus, the specialized arm for mating, is lined with receptors that can sense hormones from the female.

The California two-spot octopus is a solitary creature. How exactly they manage to find suitable mates has been one of the ocean’s best-kept secrets.

Now scientists have discovered that male octopuses have a unique way of sensing a female’s presence: they use special sensors in the arm they use for sex. Receptors in the suckers on this arm taste female sex hormones, and directly guide the arm to where it needs to go to deliver sperm, researchers report in the journal Science. (snip-MORE; click the title above)