By Anupum Pant
The brain of an octopus is the size of a walnut – Significantly smaller than that of us. Or I’d rather say the main brain of an octopus is of that size. That is because only a third of the total neurons in the body of an octopus are in its main brain. Rest of them are distributed in its eight arms.
This is the reason the arms of an octopus are not completely its own. They sort of have a mind of their own. They have the ability to do their own thinking, or at least basic coordination, problem-solving and reaction.
Even when an octopus is killed and its arms are separated from its main body, they still are able to react to stimuli, and more. That is like a severed human arm reacting to a hot kettle. The thing is, even with a walnut sized main brain, it can do so many things that our complex human brains allow us to do.
These creatures are also pretty astounding when it comes to sensing their environment with their arms (skin) and creating camouflage. They are colour blind, and yet they are able to do some amazing texture and colour replication on their skin (as seen in the video below). They can literally see using their skins. Some cephalopods like cuttle fish have the photoreceptor protein in their skin (as well as eyes). We and everything that has an eye have it only their eyes.