Living insect with eyes like trilobites'.The raspberrylike eyes bulging bulge n. 1. A protruding part; an outward curve or swelling. 2. Nautical A bilge. 3. A sudden, usually temporary increase in number or quantity: from the head of an oddball insect seem to work like no other insect eyes known to science--except perhaps those of the long-gone trilobites This list of trilobites is a comprehensive listing of all genera that have ever been included in the class Trilobita, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomina dubia . A detailed study of the eyes of the tiny Xenos peckii, parasites of paper wasps, has revealed unique vision, report Elke Buschbeck and other Cornell investigators in the Nov. 5 SCIENCE. Only the males have eyes at all. The females don't seem able to see or to fly, and they live out their entire lives inside the body of the paper wasp where they hatched. The males do leave home, bursting out of the wasp's body and spending all 2 hours of their adult lives flying around searching for paper wasps that contain suitable females. With so little time, good vision may offer a big advantage to a guy on a mission. The scientists estimate that visual processing Visual processing is the sequence of steps that information takes as it flows from visual sensors to cognitive processing. The sensors may be zoological eyes or they may be cameras or sensor arrays that sense various portions of the electromagnetic spectrum. takes up some 75 percent of the insect's brain. Each eye contains 50 lenses, a paltry pal·try adj. pal·tri·er, pal·tri·est 1. Lacking in importance or worth. See Synonyms at trivial. 2. Wretched or contemptible. number compared with more typical insect eyes like the fruit fly's 700-faceted vision contraption. Yet each X. peckii lens is as big as about 15 fruit fly facets and lies over its own retina with more than 100 photoreceptors Photoreceptors Specialized nerve cells (rods and cones) in the retina that are responsible for vision. Mentioned in: Macular Degeneration . A fruit fly facet facet /fac·et/ (fas´it) a small plane surface on a hard body, as on a bone. fac·et n. 1. A small smooth area on a bone or other firm structure. 2. feeds only eight photoreceptors. Such optical equipment could allow each lens of the parasite's eye to see what the researchers call a chunk of an image instead of just the pinpoint processed by the facet of a typical compound eye. The only structure like it, they say, occurs on fossils of trilobites. |
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