The 20th century witnessed two profound changes in regions of the world where people are well educated and science and technology flourish：Life expectancy nearly doubled，and fertility rates fell dramatically．As a result，individuals and populations are aging．
　　VirtuaIlv all educated people are aware of the graying of the United States，yet relatively few are as aware of its implications for science，technology， and human culture．Longer life is a remarkable achievement，but now we need to apply what we are learning in the natural and social sciences to redesign human cuIture to accommodate long lives． We need to find cures for Alzheimer’s disease and arthritis， develoD technologies that render many age—related frailties such as poor balance invisible in the way eyeglasses now compensate for presbyopia，and begin seriously rethinking cultural norms，such as the timing of education and retirement．
　　Longevity is the largely unexpected consequence of improvements in general living conditions． Genetically speaking，we are no smarter or heartier than our relatives were 10，000 years a90． Nonetheless。in practical terms we are more biologically fit than our great—grandparents．Robert Fogel and his colleague Dora Costa coined the term technophysio evolutionto refer to improvements in biological functioning that are a consequence of technological advances．They point out that technologies developed mostly in the past century vastly improved the quality and sustainability of the food supply． Subseauent improvements in nutrition were so dramatic that average body size increased by 50％and life expectancy doubled．The working capacity of vital organs greatly improved．Breakthroughs in manufaeturin9，transportation，energy’production，and communications contributed further to improvements in biological functionin9．Medical technology now enables full recovery from accidents or illnesses that were previously fatal or disabling．
　　Remember，however，that advances of the 20th century did not aim to increase longevity or alleviate the disabling conditions of later life．Longer life was the byproduct of better conditions for the young． The challenge today is to build a world that is j ust as responsive to the needs of very old people as to the very voun9．The solutions must come from science and technology． Unlike evolution by natural selection。which operates across millennia，improvements in functioning due to technological advances can occur in a matter of years．In fact，given that the first of the 7 7 million Baby Boomers turned 60 in 2006。there is no time to waste．To the extent that we effectively use science and technology to compensate for human frailties at advanced ages，the conversation under way in the nation changes from one about old age to one about long Iife，and this is a far more interesting and more productive Conversation to have． [444 words]
　　1．One of the radical changes in developed nations in the 20th century was that______
　　A．populations grew unexpectedly
　　B．the majority were well educated
　　C．1ire expectancy increased sharply
　　D．science and technology advanced
　　2．Facing the rapid increase of the aging population，we should______
　　A．manage to adapt our culture to it
　　B．redesign our educational systems
　　C．find cures for age—related diseases
　　D．develop technologies for old people
　　3．According to Robert Fogel and Dora Costa，improved biological functioning is______．
　　A．largely beyond our expectations
　　B．attributed to various technological advances
　　C．due to the improved quality of the food supply
　　D．inevitable with the improvement of living conditions
　　4．In the authors opinion, the world we have built is______．
　　A．to accommodate to the needs of young people
　　B．to improve living conditions for all the people
　　C．to increase the life expectancy of the majority
　　D．to attune to the needs of both old and young
　　5．The author proposes that we should______．
　　A．spare no efforts to increase life expectancy
　　B．be aware of the rapid graying of our society
　　C．apply science and technology in everyday life
　　D．try our best to improve the lives of old people