Factors to Influence

共享题干题                                              (二)
                                Factors to Influence the Life Span
根据以下的材料，回答问题。
          People are living longer than ever, but for some reason, women are living longer than men．Ababy boy born in the United States in 2003 can expect to live to be about 73, but a baby girl, about79．This is indeed a wide gap, and no one really knows why it exists．The greater longevity ( 长寿 )of woman, however, has been known for centuries．It was, for example, described in theseventeenth century．However, the difference was smaller then--the gap is growing．"
          A number of reasons have been proposed to account for the differences: The gap is greatest inindustrialized societies, so it has been suggested that women are less susceptible to work strainsthat may raise the risk of heart disease and alcoholism．Sociologists also tell us that women areencouraged to be less adventurous than men (and this may be why they are more careful drivers,involved in fewer accidents).
         Even smoking has been implicated in the age discrepancy．It was once suggested that workingwomen are more likely to smoke and as more women entered the work force, the age gap wouldbegin to close, because smoking is related to earlier deaths．Now, however, we see more womensmoking and they still tend to live longer although their lung cancer rate is climbing sharply.
        One puzzling aspect of the problem is that women do not appear to be as healthy as men．Thatis, they report far more illness．But when a man reports an illness, it is more likely to be serious.
       Some researchers have suggested that men may die earlier because their health is morestrongly related to their emotions．For example, men tend to die sooner after losing a spouse thanwomen do．Men even seem to be more weakened by loss of a job．(Both of these are linked with amarked decrease in the effectiveness of the immune system.) Among men, death follows retirementwith an alarming promptness.
        Perhaps we are searching for the answers too close to the surface of the problem．Perhaps theanswers lie deeper in our biological heritage．After all, the phenomenon is not isolated to humans.
        Females have the edge among virtually all mammalian ( 哺乳动物的 )species, in that they generallylive longer．Furthermore, in many of these species the differences begin at the moment ofconception; there are more male miscarriages ( 流产) ．In humans, after birth, more baby boys thanbaby girls die.