2015考研英语阅读集中练Whos the Smart Sibling_大学英语阅读

2015考研英语阅读集中练Whos the Smart Sibling

　　But even though the scientists were turning up birth-order patterns easily, they couldn t pin down a cause. Perhaps, one theory went, the mother s body was somehow attacking the later offspring in uterus. Maternal antibody levels do increase with each successive pregnancy. But there s no evidence that this leads to differences in intelligence, and the new study in Silence,based on records from nearly a quarter of a million young Norwegian men, strikes down the antibody hypothesis. It looks at kids who are the eldest by accident-those whose older siblings die in infancy--as well as those who are true firstborns. Both groups rack up the same high scores on IQ tests. Whatever is lowering the latterborns scores, it isn t prenatal biology, since being raised as the firstborn, not actually being the firstborn, is what counts.

　　The obvious culprits on the nurture side are parents. But it s hard to think that favoritism toward firstborns exists in modem society. Most of us no longer view secondborn as second best, and few parents will admit to treating their kids differently. In surveys, they generally say they give their children equal attention. Kids concur, reporting that they feel they re treated fairly.

　　Maybe, then, the problem with latterborns isn t nature or nurture-maybe there simply isn t a problem. Not all the research shows a difference in intelligence. A pivotal 2000 study by Joe Rodgers ,now a professor emeritus at the University of Oklahoma, found no link between birth order and smarts. And an earlier study of American families found that the youngest kids, not the oldest, did best in school. From that work, say psychologist Judith Rich Harris, a prominent critic of birth-order patterns, it s clear that the impression that the firstborn is more often the academic achiever is false.