【单选题】
Longer Lives for WildElephants
Most people think of zoos as safe places for animals, where struggles such as having difficulty finding food and avoiding predators (猛兽) don’t exist. Without such problems, animals in zoos should live to a ripe (成熟的) old age.
But that may not be true for the largest land animals onEarth. Scientists have known that elephants in zoos often suffer from poor health. Sometimes, they even become unable to have babies.
To learn more about how captivity (圈养) affects elephants, a team of international scientists compared the life spans of female elephants born in zoos with female elephants living outdoors in their native lands. Zoos keep detailed records of all the animals in their care, documenting factors such as birth dates, illnesses, weight and death. These records made it possible for the researchers to analyze 40 years of data on 800African andAsian elephants in zoos acrossEurope. The scientists compared the life spans of the zoo-born female elephants with the life spans of thousands of wild female elephants inAfrica andAsian elephants that work in logging camps (伐木场), over approximately the same time perioD、
The team found that femaleAfrican elephants born in zoos lived an average of 16.9 years. Their wild counterparts who died of natural causes lived an average of 56 years--more than three times as long. FemaleAsian elephants followed a similar pattern. In zoos, they lived 18.9 years, while those in the logging camps lived 41.7 years.
Scientists don’t know yet why wild elephants seem to get on so much better than their zoo-raised counterparts. Georgia Mason, a biologist at the University of Guelph inCanada who led the study, thinks stress and obesity (肥胖症) may be to blame. Zoo elephants don’t get the same kind of exercise they would in the wild, and most are very fat. Social lives of elephants are also much different in zoos than in the wild, where they live in large herds and family groups.
The study raises some questions about acquiring more elephants to keep in zoos. While some threatened and endangered species living in zoos reproduce (生殖) successfully and maintain healthy populations, that doesn’t appear to be the case with elephants.
It was found that, compared with female wild elephants, female zoo-born elephantsA．lived longer.
B．grew up faster.
C．died much earlier.
D．enjoyed the same life spans.
网考网参考答案：C
网考网解析：
[解析] 题干中的关键词为“compared with与…相比较；female wild elephants野生雌性大象；female zoo—born elephants园内所生雌性大象。” 根据文中第4段的1—3行：“研究小组发现，动物园出生的非洲雌象平均寿命是16.9年。而自然死亡的野生大象平均寿命是56年——是动物园大象的3倍多。”以此判断应选C项。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>
Most people think of zoos as safe places for animals, where struggles such as having difficulty finding food and avoiding predators (猛兽) don’t exist. Without such problems, animals in zoos should live to a ripe (成熟的) old age.
But that may not be true for the largest land animals onEarth. Scientists have known that elephants in zoos often suffer from poor health. Sometimes, they even become unable to have babies.
To learn more about how captivity (圈养) affects elephants, a team of international scientists compared the life spans of female elephants born in zoos with female elephants living outdoors in their native lands. Zoos keep detailed records of all the animals in their care, documenting factors such as birth dates, illnesses, weight and death. These records made it possible for the researchers to analyze 40 years of data on 800African andAsian elephants in zoos acrossEurope. The scientists compared the life spans of the zoo-born female elephants with the life spans of thousands of wild female elephants inAfrica andAsian elephants that work in logging camps (伐木场), over approximately the same time perioD、
The team found that femaleAfrican elephants born in zoos lived an average of 16.9 years. Their wild counterparts who died of natural causes lived an average of 56 years--more than three times as long. FemaleAsian elephants followed a similar pattern. In zoos, they lived 18.9 years, while those in the logging camps lived 41.7 years.
Scientists don’t know yet why wild elephants seem to get on so much better than their zoo-raised counterparts. Georgia Mason, a biologist at the University of Guelph inCanada who led the study, thinks stress and obesity (肥胖症) may be to blame. Zoo elephants don’t get the same kind of exercise they would in the wild, and most are very fat. Social lives of elephants are also much different in zoos than in the wild, where they live in large herds and family groups.
The study raises some questions about acquiring more elephants to keep in zoos. While some threatened and endangered species living in zoos reproduce (生殖) successfully and maintain healthy populations, that doesn’t appear to be the case with elephants.
It was found that, compared with female wild elephants, female zoo-born elephantsA．lived longer.
B．grew up faster.
C．died much earlier.
D．enjoyed the same life spans.
网考网参考答案：C
网考网解析：
[解析] 题干中的关键词为“compared with与…相比较；female wild elephants野生雌性大象；female zoo—born elephants园内所生雌性大象。” 根据文中第4段的1—3行：“研究小组发现，动物园出生的非洲雌象平均寿命是16.9年。而自然死亡的野生大象平均寿命是56年——是动物园大象的3倍多。”以此判断应选C项。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>
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