新理念英语学习大厅答案(4)

2019-03-03 14:01

and cotton seed oil. animal products have also been developed, although as of july 2010 none are currently on the market. critics have objected to gm foods on several grounds,

including safety issues, ecological concerns, and economic concerns. however, genetically-modified foods are here to stay. that’s not to say that food produced by conventional

agriculture will disappear, but simply that food-buying patterns will polarize (两极分化): there will be a right market for

conventional food just as there is for organic food. it may even be that gm food will become the food of preference because consumers come to appreciate the health benefits of reduced pesticide use.

the reason gm food will not go away is that we need a three-fold increase in food production by the year 2050 to keep pace with the world’s predicted population growth to ten or eleven billion. it’s not just a question of more mouths to feed either. what is often forgotten is that all these extra people will take up space, reducing the overall land available for agriculture. genetic modification is analogous to nuclear power: nobody loves it, but climate change has made its adoption imperative, says economist paul collier of oxford university. declining

genetic modification makes a complicated issue more complex. genetic modification offers both faster crop adaptation and a biological, rather than chemical, approach to yield increases. the world has 800 million hungry people. until now, food supplies have been increased by improved varieties,

pesticides and artificial fertilizers: the green revolution. now we’re on the edge of a new revolution: a genetic one.

it may well be that in the long term it is the developing world that benefits most from gm foods. it’s true that for the next ten years or so gm crops may be too expensive. but the lesson of personal computers is applicable here — once the technology has been developed for profitable crops, it will spread and become affordable for all. this doesn’t mean, unfortunately,


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