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New Tetrachromatic Glasses


A new scientific development has just been unveiled that could potentially give fishermen an inhuman edge in fish spotting abilities. Researchers from the University of Wisconsin - Madison have just announced the development of a pair of glasses that can help the wearer distinguish differences in color that are normally too subtle for the eyes of homo sapiens to detect. These color differentials, known as Metamers, are more easily seen by other animals who possess optical physiology that is more developed than ours.

As reported by, "The glasses essentially expand the vision of wearers from trichromatic, in which we see three color channels, to tetrachromatic. This would be in line with animals such as goldfish, which are able to see red, blue, green, and ultraviolet light. They contain two color filters (the glasses, that is; not goldfish) which strip specific parts out of blue light spectrum. Because each eye is receiving subtly different spectral data about blue objects, the working hypothesis — proven correct — was that tiny differences in color would appear far more noticeable."

Tetrachromacy has long been on the radar of Ichthyologists, with goldfish (read, Carp -- hint, hint) given as an example of being bestowed, as stated above, with the ability to "see" in a fourth wavelength — that of the ultraviolet.  The assumption is that there is a biological advantage conferred with the ability, such as being able to discern food under murky water conditions.

Juvenile Brown trout have also been identified as being Tetrachromats, but apparently lose the ability after their second year. Here, researchers have postulated that the diatoms and other plankton-like forage that juvenile trout feed on exhibit unique reflectance of UV-wavelength light in their carapaces, and possibly other bioluminescence similar to that seen in certain insects and marine algae.

Humans can even express more of a deficit in color sense, known as Red/Green color blindness, where the rods in the eye are mutated to lack sensitivity in that part of the visual spectrum. However, there appear to also be exceptions to this, with some people — primarily women — having been identified as being natural Tetrachromats, with an extra, fourth cone that confers the ability to differentiate metamers.

What is the practical advantage for the fisherman, you ask? Just think back to the last time you were trying spot a big rainbow trout lying on a mottled bed of pink gravel and moss. More than once, I've had to unfocus my eyes and quit looking so hard at the structure of what I was seeing, and rather concentrate on seeing the telltale flash of violet in the stripe of mature rainbows that would unmistakably show the fish's position.  Having an advantage in seeing in that part of the spectrum could put you on fish before they see you.

Regarding the new glasses, the researchers continued, "The current device works by splitting the short wavelength cone in the eye," Gundlach said. "What this means, practically, is that it only works for splitting mostly blue or violet colored objects. We're currently working on applying this to the green part of the spectrum, which is much more applicable to most things in nature."

Better sight fishing through science may be just around the corner, and in my rapidly advancing years, I'll be happy to take all the help I can get!

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