Longer Lives for Wild Elephants Most people think of zoos as safe places for animals,where struggles such as difficulty finding food and avoiding predators dont exist. Without such problems, animals in zoos should live to a ripe old agel. To learn more about how captivity 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 The team found that female African elephants born in zoos lived an average of l 6.9 years.Their wild counterparts who died of natural causes lived an average of 56 yearsmore than three times as long.Female Asian elephants followed a similar pattern.In zoos, they lived l 8.9 s years, while those in the logging camps lived 41.7 years. Another finding from the study showed that Asian elephants born in zoos were more likely to die early than Asian elephants captured in the wild and brought to zoos.Mason suggests stress in the mothers in zoos might cause them to have babies that are less likely to survive. 词汇: Ripe adj.成熟的 Captivity n.监禁;束缚 Obesity adj.过度肥胖;肥胖症
上一篇: 职称英语考试理工类的阅读理解练习题(6)
下一篇: 职称英语综合类的阅读理解练习题(29)
2017届高考英语一轮复习单元课件:必修4Unit 1《Advertising》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:选修6Unit 4《Helping people around the World》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:必修2Unit 2《Wish you were here》 ( 牛津译林版)
2017届高考英语一轮复习学案:M3 Unit2 Language》(第2课时)(牛津译林版)
2017届高考英语一轮复习学案:M3 Unit3《Back to the past》(第1课时)(牛津译林版)
2017届高考英语一轮复习单元课件:必修2Unit 3《Amazing people》 ( 牛津译林版)
2017届高考英语一轮复习语法备考:it(含解析)
2017届高考英语一轮复习语法备考:介词(含解析)
2017届高考英语一轮复习语法备考:形容词,副词(含解析)
2017届高考英语一轮复习语法备考:被动语态(含解析)
2017届高考英语一轮复习单元课件:必修1Unit 2《Growing pains》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:选修6Unit 1《Laughter is good for you》 ( 牛津译林版)
2017届高考英语一轮复习语法备考:名词性从句(含解析)
2017届高考英语一轮复习语法备考:谓语动词(含解析)
2017届高考英语一轮复习语法备考:情态动词(含解析)
2017届高考英语一轮复习语法备考:比较结构(含解析)
2017届高考英语一轮复习单元课件:必修5Unit 1《Getting along with others》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:选修8Unit 3《The world of colours and light》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:必修3Unit 1《The world of our senses》 ( 牛津译林版)
2017届高考英语一轮复习学案:M3 Unit2 Language》(第3课时)(牛津译林版)
2017届高考英语一轮复习单元课件:选修7Unit 1《Living with technology》 ( 牛津译林版)
2017届高考英语一轮复习单元课件:必修3Unit 2《Language》 ( 牛津译林版)
2017届高考英语一轮复习语法备考:定语从句(含解析)
2017届高考英语一轮复习语法备考:状语从句(含解析)
2017届高考英语一轮复习单元课件:必修5Unit 2《The Environment》 ( 牛津译林版)
2017届高考英语一轮复习学案:M3 Unit3《Back to the past》(第3课时)(牛津译林版)
2017届高考英语一轮复习单元课件:必修4Unit 3《Tomorrow’s World》 ( 牛津译林版)
2017届高考英语一轮复习语法备考:强调句型(含解析)
2017届高考英语一轮复习语法备考:冠词(含解析)
2017届高考英语一轮复习学案:M3 Unit3《Back to the past》(第2课时)(牛津译林版)