Word: molecular
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Dates: during 1990-1999
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...small, brown, furry creature inside a cage in Princeton University's molecular-biology department looks for all the world like an ordinary mouse. It sniffs around, climbs the bars, burrows into wood shavings on the floor, eats, eliminates, sleeps. But put the animal through its paces in a testing lab, and it quickly becomes evident that this mouse is anything but ordinary. One after another, it knocks off a variety of tasks designed to test a rodent's mental capacities--and almost invariably learns more quickly, remembers what it learns for a longer time and adapts to changes...
...this weakening of memory and the parallel loss of ability to learn new things easily that led Princeton molecular biologist Joe Tsien to the experiments reported last week. "This age-dependent loss of function," he says, "appears in many animals, and it begins with the onset of sexual maturity...
...recently as five years ago, all that scientists could really tell about our earliest ancestors was when they first appeared. Molecular biologists had measured the differences between human and chimpanzee DNA, then averaged the rate of genetic change over time. By calculating backward, they determined that great apes and hominids branched from a common ancestor between 6 million and 4 million years ago. But no fossils were on hand to support this scenario. The oldest hominid species known, Australopithecus afarensis (southern ape of the Afar), could be dated back only 3.6 million years. Its most famous member, Lucy, unearthed...
...romantic notion of how the Neanderthals disappeared has been around for decades: perhaps they were eliminated by interbreeding with us. Maybe we all carry a bit of Neanderthal in our DNA. Two years ago, molecular biologists tested that hypothesis by extracting some DNA from a Neanderthal fossil and comparing it with that of modern humans. Their conclusion: the differences are great enough to rule out significant interbreeding, even though such mating would have been biologically possible...
...implications are almost unimaginable - cheap, ubiquitous supercomputing, unlimited memory capacity, medical nano-devices small enough to float in the human bloodstream, and beyond - but it will be years before actual functioning molecular computers will be constructed. "This is an important stepping stone, but we still have a long way to go, " James Tour, an expert in the field who teaches at Rice University, told the New York Times. "I don't want people to think that in three to five years we'll have molecular electronics...