How Many Brains Does An Octopus Have?

You’re probably thinking an octopus, like most other animals, has only one brain. That’s if they do have a brain at all. If that sounds like something you’d say, then you are in for a huge surprise as we answer the popular question: How Many Brains Does An Octopus Have?

Be ready to be blown away by the fascinating octopus facts that we are about to share with you.


Do Octopuses Have Brains?

Yes, octopuses have brains! More than one actually. They, along with cuttlefish and squid, are believed to be the most intelligent invertebrates. These oceanic creatures are an example of progressive cognitive evolution in animals. 

They have demonstrated their intelligence in several ways. In experiments, octopuses have solved mazes and completed challenging tasks for food rewards. They can also maneuver their bodies in and out of containers. 

There is even video footage capturing the sneaky yet highly intelligent behavior of octopuses. 

How Many Brains Does an Octopus Have?

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An octopus has 9 brains. They have a central brain located between their eyes and then a “mini brain” or ganglia for each of their 8 tentacles. These 8 “mini brains” are situated at the base of their tentacles.

With all this brainpower, you’d think octopuses are the most intelligent living beings in the world. However, this is not quite the case. 

Octopuses may have 9 brains, but their brains are wired very differently from vertebrates, including humans. But, in comparison to other invertebrates, octopuses are pretty intelligent. 

How Big are Octopus Brains?

To determine the average intelligence of an animal, scientists generally use the size of the animal’s brain in relation to its body. This is not an accurate measure, but clever animals tend to have a higher brain-to-body ratio. 

That’s why it is no surprise that an octopus’s brain-to-body ratio is larger than any other invertebrate. Their ratio is also larger than most vertebrates, but not mammals. 

Octopuses share the same amount of neurons as dogs. The most popular octopus species, Octopus vulgaris, has an estimate of 500 million neurons. Two-thirds of these neurons are situated in their tentacles, and the remaining neurons are in their head. 

Why do Octopuses Have 9 Brains?

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Octopuses have 9 brains because apart from their central brain, each of their 8 tentacles has a “mini brain” that allows it to act independently. Each tentacle can taste, touch, and move without direction. 

This takes a load off the central brain. The centralized brain can exert top-down control. 

Equipped with 9 brains, octopuses can react faster and more effectively to threats because each tentacle does not signal the central brain. 

They can also refine the movement of each tentacle bypassing the work off to the “mini brain”.   

Basically, their 9 brains allow them to have localized and centralized control of their actions. 

Why is the Octopus Brain so Extraordinary?

An octopus brain is so extraordinary because it comes from an entirely different biological structure than our brains. 

Their heads have incredibly large brains. And they share a brain-to-body ratio similar to that of other smart animals. They also have a complex nervous system with as many neurons as dogs. 

Octopuses can learn through observation, use tools, and even recognize people. They are mischievous and have sneaky disguises and escape techniques. 

Why do Octopuses have Blue Blood? 

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Most octopuses live in deep cold waters. So their bodies have adapted by using a rich copper protein called hemocyanin to oxygenate their blood, rather than using our rich iron hemoglobin. 

The hemocyanin gives their blood a blue tint, which is why they have blue blood, while hemoglobin makes our blood red. 

The copper-based protein best transports oxygen molecules in cold and low oxygen conditions, making it ideal for living in the sea.

But, their hemocyanin blood does not efficiently carry oxygen. This is why octopuses prefer cooler, highly oxygenated water. 

Other Interesting Facts About an Octopus

  • Octopuses have 3 hearts. One for circulating blood around the body and two for pumping blood past the gills to get oxygen. 
  • Octopuses are usually antisocial creatures, with very few exceptions.
  • They have a lifespan of 2 to 5 years.
  • Octopuses do not have bones
  • Octopuses can regenerate a severed tentacle, as well as a new “mini brain”.
  • They have over 2 000 suckers. Each sucker has chemo-receptors so they can taste everything they touch. 
  • They kill their prey by piercing it with their sharp tongue and injecting poisonous saliva. 
  • Octopuses have both short and long-term memory. 
  • Octopuses grow incredibly fast and gain up to 2% of their body weight a day. 
  • An octopus can sometimes suffer from autophagy or self-cannibalism. This is caused by stress and can result in them eating their own tentacles. 


As crazy as it may sound, octopuses do, in fact, have 9 brains. Their individual brains play a huge role in their unique personalities and intelligence. This is why octopuses are the smartest invertebrates on earth. 

If you’re thinking of octopus names, you can check out our other blog post!

Sniff Around  Is a top blog that talks about Pet animals and various types of animal. Also talks about how they live and interact with people and environment.

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