FLICKR, SILKE BARONThe eyes of mantis shrimp (Haptosquilla trispinosa) are impressive. Each eye, which sits atop a stalk that projects from the shrimp’s head, is able to perceive distance on its own through a process called trinocular vision, and can perceive circularly polarized light. And according to a study published this week (January 23) in Science, the crustaceans visualize colors very differently than all other animals.
With 12 different photoreceptors, including four that respond to wavelengths in the ultraviolet light spectrum, some researchers had suspected that mantis shrimp were better distinguishers of color than humans, with just three: red, green, and blue. To test this theory, marine neuroscientist Justin Marshall of the University of Queensland in Brisbane, Australia, and his colleagues trained shrimp to recognize each of 10 different colors in the visible light spectrum, then tested their ability to discriminate between those and other colors. Surprisingly, the shrimp did not fare well: when the wavelengths of colors tested were less than 25 nm apart, the shrimp failed to distinguish them.
“With 12 receptors, you’d think that they can detect colours much better than any other animal,” Marshall told National Geographic’s ...