An interesting part of the recent book An Immense World was its coverage of how mantis shrimp likely don't use photoreceptors like human's do.
Marshall now thinks that the mantis shrimp sees colors in a unique way. Rather than discriminating between millions of subtle shades, its eye actually does the opposite, collapsing all the varied hues of the spectrum into just 12.
From Science: "A Different Form of Color Vision in Mantis Shrimp"
The mantis shrimps (stomatopods) can have up to 12 photoreceptors, far more than needed for even extreme color acuity. Thoen et al. conducted paired color discrimination tests with stomatopods and found that their ability to discriminate among colors was surprisingly low. Instead, stomatopods appear to use a color identification approach that results from a temporal scan of an object across the 12 photoreceptor sensitivities. This entirely unique form of vision would allow for extremely rapid color recognition without the need to discriminate between wavelengths within a spectrum.
Marshall now thinks that the mantis shrimp sees colors in a unique way. Rather than discriminating between millions of subtle shades, its eye actually does the opposite, collapsing all the varied hues of the spectrum into just 12.
From Science: "A Different Form of Color Vision in Mantis Shrimp"
The mantis shrimps (stomatopods) can have up to 12 photoreceptors, far more than needed for even extreme color acuity. Thoen et al. conducted paired color discrimination tests with stomatopods and found that their ability to discriminate among colors was surprisingly low. Instead, stomatopods appear to use a color identification approach that results from a temporal scan of an object across the 12 photoreceptor sensitivities. This entirely unique form of vision would allow for extremely rapid color recognition without the need to discriminate between wavelengths within a spectrum.