It was found that octopus skin contains the pigment proteins normally found in eyes, making it responsive to light.
Octopuses are masters of camouflage, changing textures, color and patterns of their skin in order to blend with the environment and communicate with each other.
As this was not enough, new research has found that octopus skin can sense light.
Researchers believe that octopus rely on their vision in order to change color. Octopus are color blind, but they use their eyes to sense the color in their surroundings, then relaxing and contracting their chromatophores, the tiny bags filled with color pigments suitably. Chromatophores take any of the three basic pattern templates in order to camouflage them. The whole process takes only one-third of the second.
In 1960’s, experiments proved that chromatophores react to light, this imply that they can be controlled without feedback from the brain.
Biologists from University of California, Santa Barbara, Desmond Ramirez and Todd Oakley took several skin samples from a species of octopus known as California two spot.
They then placed the samples collected in a petri dish using insect pins. They have then used light emitting diodes to shine lights of different wavelengths onto the sample skin.
They found that when the skin was exposed to continuous bright white light, chromatophores expanded rapidly and remained expanded, pulsating rhythmically.
When the sample was exposed to red light, the muscles contracted rhythmically but did not expand the chromatophores.
Octopus aren’t the only species that can see using their skin, but there are several other species that contain opsins in their skin making them sensitive to light.
The study presents the first evidence that octopus skin is sensitive to light.