来自《耶鲁大学开放课程：有关食物的心理学、生物学和政治学 第2集 第2集》

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  and we've got problems.
  然后我们就有麻烦了
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  This is a normal weight laboratory rat
  这是一只体重正常的实验鼠
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  given much more than it would--
  如果我们给它标准的实验室饲料
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  could necessarily eat of standard laboratory food.
  即使食物分量超出了它的食量
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  Now in this particular case,
  在这种情况下
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  these animals will not overeat on the healthy balanced food
  它们并不会吃过量的健康食品
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  and won't gain excess weight,
  因此不会变胖
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  they'll maintain a normal weight.
  所以一直保持着标准的体重
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  But if you throw off the environment,
  如果让它们换个环境
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  in this case, the animal's biology,
  这种情况下 这些动物的生理特性
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  it's drive for certain nutrients
  即它们有多少动力去获取某些营养元素
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  is in concert with the food it has access to.
  是与其食物源状态有关的