Octopi are a special kind of invertebrate. We all know about their eight arms and color-changing, camouflaging abilities, as well as an ink self-defense. But we often fail to realize that these fascinating quirks are only a portion of what helps an octopus survive. Their great evolutionary advantage comes from their intelligence, which is often overlooked as an advantage for survival. Unlike many of the less developed invertebrate animals, members of the cephalopod family (Like octopus, cuttlefish, and squid,) are much more intelligent than they might seem. Let's explore the extent of their intelligence, and exactly how much we know about their lives.
Humans are octopus are, as you can probably guess, not closely related. However, both species have evolved to make their brain the primary organ when it comes to survival. This connection allows us to draw similarities in human and octopus development. They are an entirely different species with an intelligence that we don't even fully grasp yet.
Octopi have about 500 million neurons in their bodies. Humans have far more, 100 billion, but in comparison with other invertebrates, this shows an extraordinary level of development. While the largest collection of neurons is in the brain for humans, in an octopus they are in the arms. This gives the illusion of "eight brains", and allows for a high level of control and sensation in their limbs that is independent from their central brain.
Advantages for Life in the Deep
In captivity, octopi have displayed highly advanced capabilities. From squirting water at humans they dislike, to partially successful escape attempts, their activities certainly set them apart from the other animals in the aquarium, that's for sure. But what about their life in the depths?
The concentrations of neurons in their arms allow for a better grip on objects and prey through the suckers. These arms can not only feel touch, but they can also smell and taste. An octopus' lack for bones also allows it to squeeze into small places, many times through a learned behavior, like walking.
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