The octopus can "see" with skin
A new body of research published in The Journal of Experimental Biology indicates that cephalopods, including the octopus and the squid, could be able to 'see' their surroundings with their skin cells.
An octopus can detect the color of their surroundings and camouflage to avoid being seen by potential predators. The research focused on a study of proteins found in the animal's eye, that are also present in their skin, leading to conclusions that their camouflage abilities rely on eyesight.
Chromatophores, or pigmentation cells, exist in both humans and cephalopods alike. But for the octopus, they are able to contract and expand, leading to immediate changes in skin color.
By exposing samples of octopus and squid skin to light, researchers observed that the samples responded to changes drastically, indicating that they contain the sensory neurons necessary for light detection. These are called the opsin genes.
Because this animal is believed to be colorblind, and not able to distinguish different hues, this discovery expands on how they adapt to their environment by reacting to extremes in the light spectrum.