OCTOWHAAAT!? Amazing facts about the Octopus
- Purple Dive
- Aug 6
- 4 min read
Reading books like Peter Godfrey-Smith's "Other Minds" and watching documentaries like "My Octopus Teacher" have cemented in my mind the absolute genius as well as my irrevocable admiration for these fantastic creatures. So in homage of the magnificent octopus; here are some amazing facts about the octopus to blow your mind!
Lets start with the basics
The plural of octopus is Octopuses, however Octopi and Octopodes are also accepted terms. This is because, the scientific name for octopus is Octopoda. They belong to the class, Cephalopoda and the collective noun for octopus is a consortium.
And now for some numbers

Octopus are believed to have existed for hundreds of millions of years, with the oldest fossil found to be 296 million years old. That's not quite as long as sharks, but still pretty impressive! There are known to be over 300 different species of octopus. The largest being the Giant Pacific Octopus. This beast can weigh up to 70kg and can be as long as 6m, with an impressive arm span of 4m! The smallest octopus is the Octopus wolfi or star-sucker pygmy octopus. In contrast, this little guy is only 2.5cm long and weighs less than 1g.
Beautiful, crafty and deadly
While all octopus species have venom in their bite, the small but mighty, blue-ringed octopus is the most deadly of them all! Usually only a mere 5cm in length and misleadingly beautiful, with its blue ring design; this tiny octopus can deliver enough of it's venom to kill 26 humans! The venom itself is neurotoxic, causing muscle paralysis and is 1000 times more deadly than cyanide!
To help the octopus escape a dangerous situation, they are able to release an ink, which forms a black cloud that not only confuses and disorientates any predators masking sight, smell and taste; but the substance found in the ink, "tyrosinase", can actually cause physical irritation to those who come into contact with it. Amidst this confusion, the crafty octopus simply slips away cunningly!
Clever and full of heart!
Octopuses have 3 hearts! This helps them pump their blood around more efficiently. Two brachial hearts deliver oxygenated blood from the gills to the one systemic heart which then pumps that blood around the body. Unlike humans, who have iron-based blood; octopuses have copper-based blood called haemocyanin. This is more efficient at transporting oxygen and is also the reason their blood is blue!
We know from many stories of octopuses' remarkable intelligence from scientists, but did you know each of their arms (they are not in fact tentacles) thinks for itself? The octopus has one of the best brain-to-body ratios, and two-thirds of their neurones lie in their arms. Each arm has a collection of neurones in its base, which essentially acts as a mini-brain. This allows for independent movement and gathering of environmental information. Such goes the legend that they have 9 brains.

Arms vs. tentacles
An octopus does have eight limbs. But technically, they're known as arms, not tentacles. Octopuses are famous for their eight sucker-covered arms, whereas squids, from giant Architeuthis dux to the appetizer-size critters served at restaurants, swim with even more appendages: eight arms and two tentacles. However, most people use both terms such as in the passage below
“So how does this partially de-centralized nervous system work? The octopus does, in fact, have a central brain located between its eyes containing about 180 million neurons. This is the part of the nervous system that determines what the octopus wants or needs, such as if it needs to search for food. These are sent as messages through groupings of neurons. Commands like “search for food” are then received by each of the tentacles, who all have their own smaller, independent brains. With these commands in mind, each tentacle gathers its own sensory and position data, processes it, and then issues its own commands on how to move by stiffening or relaxing different parts of the arm, all without consulting the central brain upstairs. As the tentacle moves, it keeps collecting and processing sensory information, and any relevant information, such as the location of food, gets sent back to the central brain to make larger decisions.”
A tragic love story
Reproduction causes death! After impregnating a female, the male will die (after behaving like a bit of tit for a while). The female, meanwhile, incubates her (maybe 400,000) eggs for several months, making sure they are safe and happy! Then, once her eggs hatch, she will begin her death process; Her body will undergo cellular suicide starting at the optic glands and continuing throughout the rest of her tissues and organs, killing her one cell at a time, eek!
As promised, some amazing facts about the octopus! For more fascinating facts about octopuses read our other blogs :
And I encourage you to watch any documentary, read any books and discover research on these fabulous and complex beings!
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