Female octopuses die after their eggs have hatched.
Aside from the fact that male octopus typically dies a few months after mating, the female octopus also dies shortly after their eggs hatch. The duration of egg incubation normally takes 2 to 10 months, depending on the species and water temperature. During which, the mother octopus stops eating, and only focuses on protecting her eggs from any danger.
Mating may take up to several hours.
When mating, the male octopus will insert his hectocotylus into the female’s mantle cavity and deposit spermatophores. The hectocotylus is the modified arm of the male octopus which they use to transfer sperm to the female. Depending on the species, the mating may take up to several hours.
However, there is a risk of the male octopus being eaten during mating due to the cannibal nature of the female octopus. To prevent this, they either mate in a distance, or the male octopus will mount onto the back of the female octopus, leaving time for his escape if things go wrong.
All octopuses have venom.
When an octopus catches its prey, it breaks into the shell and injects its venomous saliva into the prey to paralyze or kill it. Although all octopuses have venom, not all of them are dangerous to humans. Only the blue-ringed octopus is fatal just with one bite.
The blue-ringed octopus' venom is fatal.
The blue-ringed octopus is the world’s most venomous marine animal. This octopus can paralyze and kill an adult human with a single bite. They are commonly found in the coral reefs and tide pools in the Indian and Pacific oceans.
Octopus has decentralized brains.
Octopuses have decentralized brains and the majority of its neurons live in the arms. Those neurons assist the arms to independently touch, taste, and have their own basic motions giving the impression that octopus has nine brains.
Deep-sea octopuses can't produce ink.
All octopuses can produce ink except for those octopuses that live in the deep open ocean. The octopuses’ ink comes from the ink sacs in their gills. They squirt ink when they face danger and need to escape from their predators. Their ink is accompanied by mucous when produced.
Almost all octopuses are predatory.
The bottom-dwelling octopuses feed mainly on polychaete worms, whelks, clams, crustaceans. On the other hand, open-ocean octopuses feed mainly on other cephalopods, prawns, and fish.
Octopuses can regrow their arm if they lose one.
These soft-bodied octopuses are invertebrates – they don’t have bones. So their tentacles or “arms” are vulnerable to damage. The regrowth process will start as soon as they lose their tentacle or after it has been damaged.
An octopus can change color in an instant.
Octopuses can change their skin colors in the blink of an eye! The ‘chromatophores’, special cells of the octopus, are the reason behind their amazing transformation. These special cells beneath their skin have thousands of colors.
Octopuses 101 | Nat Geo Wild
August 24, 2017