The Octopus Painting

from my 50 eyes in 50 days project. Eyes really are the windows to the soul. As a contemporary animal artist, I am drawn to the eyes. The eyes are what humans see in non-human animals as a kinship, and as a result, this realization is one of the many aspects that connect us to the natural world. Animals like humans and birds see color using a combination of light-receptive cone cells, each of which contains pigments that are sensitive to a different part of the visual spectrum. It’s only by combining information from different cone cells that colors can be properly distinguished. Hence, when a person lacks a particular type of cone, they are considered colorblind. Octopi and other Cephalopods only have a single type of light receptor, which means they should not be able to distinguish color at all. And yet, many octopuses, squids and cuttlefish have color-changing skin that’s used for elaborate camouflage and courtship rituals. Clearly, these colorblind animals have become masters of color manipulation, but how? The key may lie in the bizarre shaped pupils, which act like prisms, scattering white light in all directions. This effect, called chromatic aberration, is something round-pupiled animals try to avoid, although you may have experienced it if you’ve ever had your eyes dilated. Instead of focusing light through a narrow pinhole like other animals, cameras, and telescopes, cephalopod pupils blow light out. Once light has been separated into its component wavelengths, cephalopods can use physical tricks—for instance changing the depth of the eyeball, or altering the distance between lens and retina—to focus different wavelengths of light on the retina individually. This allows for colors to be discriminated.