All octopuses have poison, but few are fatally dangerous. The large blue-ringed octopus, however, is considered one of the most venomous animals known; the venom of one is enough to kill ten adult humans. Although octopus and squid are formidable fighters in nature, they are usually not dangerous to people. That doesn't mean they're always harmless.
Some species are especially well equipped to defend against larger creatures, and are strong enough to kill a human if they feel threatened. All octopus, cuttlefish and some squid are poisonous, according to a new study. The blue-ringed octopus is the most venomous of all octopus. This type of octopus has venom that contains tetrodotoxin, a substance that acts as a neurotoxin for humans.
It's important to note that all of the encounters listed occurred after humans invaded the octopus's personal space or territory, so unless you're a professional, it's best to admire the Giant Pacific from afar. Although octopus bodies are soft and boneless, they have hard beaks made of chitin, the same substance that forms the exoskeletons of arthropods such as insects, spiders and crustaceans, Trautwein told Live Science in an email. The bite of the Pacific Giant Octopus will not only hurt, but it will also inject poison into its target (although this poison is not deadly). Stories, stories and fantasies (to entertain or instil fear in children) were often told of giant octopuses large enough to attack and swallow an entire ship if they did.
However, octopuses don't just use their intelligence and appearance for fun; if they feel threatened or uncomfortable, the Pacific Giant Octopus has been known to defend itself against humans. With three hearts, nine brains and eight arms, octopuses seem equipped to tackle almost any task they decide on. Of the 300 species of octopus in the different oceans of the world, only four species of blue-ringed octopus pose a real threat to humans. While it was undoubtedly an unpleasant experience, it is likely that the baby octopus acted out of fear, feeling threatened after being pulled out of the water and placed near the woman's mouth.
The driver is easily separated from the octopus, which quickly returns to the ground to camouflage itself. Another fascinating fact is that most octopus species are nocturnal, so by default, they hunt to eat at night. Like octopus and some squid, this cuttlefish is poisonous and its muscles contain a highly toxic compound. Once again, the octopus was not directly attacking the diver, but seemed to frown at the invasion of his personal space.
Octopuses are often prey to seabirds, fish, sea otters, etc. and, like any living thing, they have unique defense mechanisms to defend themselves against predators. Octopus venom also appears to contain proteins similar to those of other venomous creatures, such as snakes. The saliva of the giant Pacific octopus contains the proteins tyramine and cephalotoxin, which paralyze or kill prey.