Word: sprouted
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Dates: during 1990-1999
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...gene nicknamed "sonic hedgehog" (after the popular video game Sonic the Hedgehog) determines the fate of neurons in the spinal cord and the brain. Like a strong scent carried by the wind, the protein encoded by the hedgehog gene (so called because in its absence, fruit-fly embryos sprout a coat of prickles) diffuses outward from the cells that produce it, becoming fainter and fainter. Columbia University neurobiologist Thomas Jessell has found that it takes middling concentrations of this potent morphing factor to produce a motor neuron and lower concentrations to make an interneuron (a cell that relays signals...
What guides an axon on its incredible voyage is a "growth cone," a creepy, crawly sprout that looks something like an amoeba. Scientists have known about growth cones since the turn of the century. What they didn't know until recently was that growth cones come equipped with the molecular equivalent of sonar and radar. Just as instruments in a submarine or airplane scan the environment for signals, so molecules arrayed on the surface of growth cones search their surroundings for the presence of certain proteins. Some of these proteins, it turns out, are attractants that pull the growth cones...
Temperature and rainfall patterns would shift in unpredictable ways. That might not pose a problem for agriculture, since farmers could change their crops and irrigate. Natural ecosystems that have to adapt on their own, however, could be devastated. Observes Oppenheimer dryly: "They cannot sprout legs and move to another climate." Perhaps a third of the world's forests, he says, might find themselves living in the wrong places...
...zebrafish, the Hox genes switch off earlier, perhaps to ensure that a flexible fin ray (useful for swimming) will form in the place of feet. Duboule speculates that if these genes could be tricked into staying on just a bit longer, the fins of the zebrafish might sprout appendages suggestive of primitive feet...
...meditations on the life of the spirit. If the line between fact and fiction seems to blur, Allende explains, "magical realism is not a literary device; it's how I live." Growing up in Santiago, she remembers the great aunt "who at the end of her life began to sprout the wings of a saint," and the clairvoyant grandmother who, Allende insists, could move a sugar bowl across the table with her mere gaze. And she tells of how, at eight, she was molested by a fisherman and found him dead the next morning...