The Octopus: Fascinating Critter Facts

Romina Bayer

I think there is no doubt that octopuses are fascinating creatures! Every time I encounter an octopus on my dive, I know it is going to be a good one!


But what makes octopuses so special? Why are we so drawn to them? 


In this article, we will uncover some of the most asked questions around octopuses.


What makes octopus special?


Did you know that Octopuses have 3 hearts, 9 brains, and blue blood?


Die TG-6 verfügt über around 300 species of octopus worldwide, and octopuses can be found in every ocean.

Die Giant Pacific Octopus is considered the largest of all species and can weigh over 327 kg (600 pounds) and up to 9 meters (30 feet) across in length. The smallest octopus species on the other hand is the Octopus Wolfi: it is smaller than 2.5cm (1 inch).


Are octopuses intelligent?


Octopuses are very intelligent creatures. Just consider that: Octopuses have 9 brains!


Why do octopuses have 9 brains?


They have eight arms, and often it may seem like each of their arms has a mind of their own. And they do! In addition to their central brain, they have a mini-brain in each of their arms. Those mini-brains allow the arms to act completely independently from each other. 


In addition to that, octopuses also have an excellent sense of touch. Most octopus species have suction cups on the bottom of each of their arms. Those suckers in turn have receptors that enable them to taste what it is touching. How fascinating is that?


Octopuses are also naturally very curious: whenever you encounter them on your dive it is worth slowing down, giving the octopus some space, and waiting for him to get comfortable. Often times you will notice that the octopus will become curious about you and might even start examining you!


Do octopuses have 3 hearts?


It’s true, octopuses have 3 hearts! Not 1, not, 2, but 3!


Two of the hearts are pumping blood to the gills. The additional third heart, which is also larger, circulates blood to the rest of the body. 


If you have more than one heart, does that also mean you have an increased capability for love?🤔

What’s the plural of octopus?


That is a question you will encounter again and again among scuba divers!

According to the Oxford English Dictionary, the standard plural in English of octopus is octopuses.

The word octopus is originated in the Greek language: októpus means “eight-foot”. Sometimes you might still hear people use the Greek plural form, which is “octopodes”.

Octopi” is another version commonly used, however, this plural version is formed according to rules for Latin plurals and is incorrect. 

Mystery solved.


Are octopus fish?


Nope, Octopuses are not fish. Octopuses are mollusks and belong to a unique class of mollusks known as cephalopods. In this class of cephalopods, you can also find squid and cuttlefish, which means they are closely related and also similar in many ways.

Octopuses have no skeleton- they are invertebrates. This means that their bodies are very soft, and it allows them to squeeze into tiny holes and crevices.

Fish on the other hand are vertebrates: they have a backbone and a skeleton.


Are octopuses dangerous?


Octopuses are generally not aggressive towards people.

Generally speaking, all octopuses have venom, but very few are fatally dangerous.


Die blue-ringed octopus, however, is considered one of the most venomous creatures. It is a small species of octopuses that grows 12 to 20 cm (5 to 8 inches) in size and might seem adorable at first glance.


The psychedelic coloring and pattern appear when the blue-ringed octopus feels threatened. As a warning signal to potential predators, they use bright blue rings that appear all over its body.  


Beautiful to look at (and makes for a great photo opportunity), not so good to touch! But anyway: remember, we don’t want to be touching any of the sea creatures when underwater. And please never threaten the animal on purpose, just because you would like to take a good picture of it.

Blue-ringed Octopus: one of the most venemous animals

And a little film recommendation at the end: “My Octopus Teacher” has shown beautifully how intelligent those little creatures are! If you haven’t seen it already, here is your plan for tonight! 😉


Have you already encountered and photographed an octopus on your dives? What is your favorite octopus fact? Let us know in the comments below!

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