Word: limbed
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Dates: during 1990-1999
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...could be involved as well, including homeobox genes that are not Hox genes (that is, they do not affect the overall structure of an animal). Last year Sean Carroll, a developmental biologist at the Howard Hughes Medical Institute in Madison, Wisconsin, showed that a homeobox gene involved in insect-limb formation also controls the genetic signals that paint spots on butterfly wings. In essence, says Carroll, butterflies use an old gene to perform a new trick. "Evolution did not have to invent new genes," he observes. "One basic toolbox gives nature enormous potential for diversity...
Another well-documented example of the brain's need to fill in the blanks is the phenomenon of phantom limbs. When an arm or a leg is amputated, the victim almost invariably "feels" sensations like pain or itching, often very strongly, in the missing limb. What's happening? The brain carries within it a mental map of the body, a well-formed sense of where every part is in relation to every other. That's why it's possible for you to extend your arm and then, with your eyes closed, bring it in to touch the tip of your...
Even when a limb is gone, its place on the mental map remains, and the neurons formerly responsible for processing sensations from it occasionally fire at random-the sensory equivalent of Mickey Mouse hallucinations. The brain also attempts to make up for the deficit physically, perhaps, suggests Ramachandran, by sprouting new sets of connections. Because neurons that process information from the arm are near those that handle the face, for example, these new connections can cause a blindfolded patient to think a gentle touch on the face is really a touch on a missing fingertip. Says Ramachandran: "Reorganization can occur...
...dull, self assured stock hero, with a limited range of emotion. Gere's Lancelot does convince the audience that he really could rival Arthur for the Queen's affections. He may not have the commanding voice and imposing presence of Connery's Arthur, but he risks life and limb for Guinevere on several occasions, and isn't afraid to grunt and sweat while doing...
...life. Itook risks without a second thought, some of thememotional ones. Youth had something to do with it,but really I was trying to replace what I'd givenup for lost--a familiar life of assured friendshipand love. And I did it by taking chances, goingout on limb after limb, hedging my bets on wildspeculations, all so that I wouldn't have to facethe changes that were happening. Many times I wasburned, but I never crashed. May be it was sheerforce of will, maybe it was knowing that I wasnever without the support of my family. And maybeit...