79 Population Growth
The growth of population during the past few centuries is no proof that population will continue to grow straight upward toward infinity and doom. On the contrary, demographic history offers evidence that population growth has not been at all constant. According to paleoecologist Edward Deevey, the past million years show three momentous changes. The first, a rapid increase in population around one m illion B. C., followed the innovations of tool making and tool using. But when the new power from the use of tools has been exploited, the rate of world population growth fell and became almost stable. The next rapid jump in population started perhaps 10,000 years ago, when mankind began to keep herds, plow and plant the earth. Once again when initial productivity gains had been absorbed, the rate of population growth abated. These two episodes suggest that the third great change, the present rapid growth, which began in the West between 250 and 350 years ago, may also slow down when, or if, technology begins to yield fewer innovations. Of course, the current knowledge revolution may continue without foreseeable end. Either way - contrary to popular belief in constant geometric growth - population can be expected in the long run to adjust to productivity. And when one takes this view, population growth is seen to represent economic progress and human triumph rather than social failure.
初三英语单词表:Unit8
初中英语常见错误之I系列
初中英语常见错误之P系列
初中英语词汇初二(字母)下 m-z
初三英语单词表:Unit5
初二英语英语(下册)重点词组与句型
初三英语单词表:Unit7
初三英语单词表:Unit1
初三英语单词表:Unit14
初三英语单词表:Unit10
初中英语常见错误之U系列
初三英语单词表:Unit3
初二英语上册单词表-外研版(一)
初中英语单词:同性恋用英语怎么说
初中英语常见错误之K系列
初中英语常见错误之H系列
英语单词常见错误--中考英语考前必备错题集
初中英语词汇初二(单元) Unit15-20
初中英语词汇初二(字母)上 a-h
初中英语常见错误之T系列
初二英语上册单词表-外研版(三)
初中英语常见错误之V系列
初三英语单词表:Unit6
初二英语上册词组总复习(A-C)
初中英语词汇初二(单元) Unit21-28
英语热词:世界杯上的“反歧视日”
潮词解析:“炫富”英语怎么说
初中英语词汇初二(字母)下 a-l
初二下学期期中考试词组汇总140个
初三英语单词表:Unit2
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英语试题 |
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