Fish's eyes apparently glow to pick up hard-to-detect hues
CHARLESTON, S.C. — The greeneye fish views its stygian home through fluorescent lenses that turn one color into another, researchers propose, making glowing green images of hard-to-see violet objects.
“Crazy” is what Yakir Gagnon of Duke University cheerfully called the fish-vision idea he and his colleagues presented January 4 at the annual meeting of Society for Integrative and Comparative Biology. Fluorescent materials known to science so far, he explained, respond to incoming light by glowing in a different color in all directions. Yet lenses on the bulging, upward-looking Chlorophthalmus fish appear to have materials that direct that fluorescent glow in the same direction and pattern as incoming light.
Like many deep-sea fishes, greeneyes have only one kind of light-detecting pigment in the retina, the surface at the back of the eye that catches images. That pigment is optimized to pick up a particular wavelength of g