Mantis shrimps are the tiny, colorful badasses of the sea. Not only do they have an unparalleled physical prowess, but they have four times as many types color-sensitive cones as humans. However, this doesn’t translate to unimaginable levels of color detection like it would seem. Mantis shrimp actually have a visual system that has never before been discovered in the animal kingdom. The study was led by Hanne Thoen of the University of Queensland and was published in Science.
In the eye, cones are the types of cells that allow the detection of color. Humans have three types of cones, or “color channels”: red, blue, and green. Every color we are able to perceive comes from combinations of these colors. Our entire visible spectrum occupies wavelengths between 390 to 700 nanometers, which isn’t half bad, relative to some other animals.
Mantis shrimp are able to detect light from 300-720 nm, which begins in near-infrared, spans our entire visible spectrum, and tapers off in ultraviolet. Thoen et al. were able to determine that mantis shrimp have an astonishing twelve different color channels, which should mean that they should have an exceptional ability to differentiate between colors.
The experiment was carried out by training mantis shrimp to associate food with a particular color. Theoretically, they should have been more adept than humans at discriminating between different shades, but that was not shown to be the case. The task got especially difficult when colors were close together on the spectrum, such as red and orange. This made the researchers very curious about why the mantis shrimp would have so many channels if they weren’t able to tease out different colors very well. They found that even though the mantis shrimp isn’t able to perceive color very well by our standards, they use an entirely different visual mechanism that has never been seen before in the animal kingdom.
While the human brain uses color in order to provide contrast and make out details in objects, the mantis shrimp evolved quite differently. Rather than discriminate between colors, the shrimp merely recognize it while quickly scanning their surroundings. By not taking the time to interpret the colossal amount of color information they are able to take in, they can make much faster decisions about determining predators, friends, or potential food.
Because this type of visual system has never been seen before, there is much to learn about what is happening at the cellular level. Researchers speculate that better understanding this new way of seeing could have some practical applications for modern cameras. High definition cameras take in a great deal of data to make the clearest picture possible, but it could be possible that the mantis shrimp holds clues to making them process the information more efficiently.