Word: known
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Dates: during 1980-1989
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Humanity already benefits greatly from the genetic heritage of little-known species. Some 25% of the pharmaceuticals in use in the U.S. today contain ingredients originally derived from wild plants. Hidden anonymously in clumps of vegetation about to be bulldozed or burned might be plants with cures for still unconquered diseases. "I know of three plants with the potential to , treat AIDS," said Janzen. "One grows in an Australian rain forest, one in Panama and one in Costa Rica...
...through the Caribbean and floods devastated Bangladesh, reminders of nature's raw power. In Soviet Armenia a monstrous earthquake killed some 55,000 people. That too was a natural disaster, but its high casualty count, owing largely to the construction of cheap high-rise apartment blocks over a well-known fault area, illustrated the carelessness that has become humanity's habit in dealing with nature...
...carbon dioxide, once thought to be exclusively responsible for the greenhouse effect, is now known to cause only half the problem. The rest comes from other gases. Chlorofluorocarbons, or CFCs, are not only destroyers of the stratosphere's ozone layer but powerful greenhouse gases as well. So are nitrogen oxides, which are pollutants spewed out of automobile exhausts and power-plant smokestacks. Another greenhouse gas is methane, the primary component of natural gas. Methane is also generated by bacteria living in the guts of cattle and termites, the muck of rice paddies and the rotting garbage in landfills. Each...
...known nonfossil energy sources, only two are far enough along in their development to be counted on: solar and nuclear, neither of which generates any greenhouse gases at all. Solar power is especially attractive. It produces no waste, and it is inexhaustible. Not all solar power comes directly from the sun: both wind and hydroelectric power are solar, since wind is created by the sun's uneven warming of the atmosphere and since the water / that collects behind dams was originally rain, which in turn was water vapor evaporated by solar heating...
...containment walls and release radioactivity. One way to prevent a meltdown is to make sure the fuel is always surrounded with circulating coolant -- ordinary water in most commercial reactors. To guard against mechanical failures that could interrupt the transfer of heat, most reactors employ multiple backup systems, a strategy known as "defense in depth...