2008年大学英语六级阅读练习 2

　　A naked mole rat colony, like a beehive, wasp’s nest, or termite mound(防蚁丘), is ruled by its queen, or reproducing female. Other adult female mole rats neither ovulate(排卵) nor breed. The queen of the largest member of the colony, and she maintains her breeding status through a mixture of behavioral and, presumably, chemical control. Queens have been long-lived in captivity, and when they die or are removed from a colony one sees violent fighting for breeding status among the larger remaining females, leading to a takeover by a new queen.
　　Eusocial(群居的) insect societies have rigid caste(等级的) systems, each insect’s role being defined by its behavior, body shape, and physiology. In naked mole rat societies, on the other hand, differences in behavior are related primarily to reproductive status (reproduction being limited to the queen and a few males), body size, and perhaps age. Smaller non-breeding members, both male and female, seem to participate primarily in gathering food, transporting nest material, and tunneling, Larger non-breeders are active in defending the colony and perhaps in removing dirt from the tunnels. One work has suggested that differences in growth rates may influence the length of time that an individual performs a task, regardless of its age.
　　Cooperative breeding has evolved many times in vertebrates(脊椎动物), but unlike naked mole rats, most cooperatively breeding vertebrates(except the wild dog, Lycaon pictus) are dominated by a pair of breeders rather than by a single breeding female. The division of labor within social groups is less pronounced among other vertebrates than among naked mole rats, colony size is much smaller, and mating by subordinate females may not be totally suppressed, whereas in naked mole rat colonies subordinate females are not sexually active, and many never breed.
　　1. Which of the following most accurately states the main idea of the passage?
　　A. Naked mole rat colonies exhibit social organization based on a rigid caste system.
　　B. Behavior in naked mole rat colonies may well be a close vertebrate analogue to behavior in eusocial insect societies.
　　C. The mating habits of naked mole rats differ from those of any other vertebrate species.
　　D. Naked mole rat colonies are the only known examples of cooperatively breeding vertebrate societies.
　　2. According to the passage, the following explanatory variables accounts for naked mole rat behavior EXCEPT_________
　　A. age B. size
　　C. growth rate D. reproductive status
　　3. In which of the following ways does the performance of tasks in naked mole rat colonies differ from task performance in eusocial insect societies?
　　A. In naked mole rat colonies, all tasks are performed cooperatively.
　　B. In eusocial insect societies, reproduction is limited to a single female.
　　C. In naked mole rat colonies, breeding is limited to the largest animals.
　　D. In naked mole rat colonies, the performance of tasks is less rigidly determined by body shape.
　　4. Which of the following is a supposition rather than a fact concerning the queen in a naked mole rat colony?
　　A. She exerts chemical control over the colony.
　　B. She is the largest member of the colony.
　　C. She mates with more than one male.
　　D. She is the only breeding female.
　　5. What can you infer from the passage about breeding among Lyeaon pictus?
　　A. An individual’s ability to breed is related primarily to its rate of growth.
　　B. Breeding is the only task performed by the breeding female.
　　C. Breeding in the social group is not cooperative.
　　D. Breeding is not dominated by a single pair of dogs
　　答案：
　　1.B 主旨题.根据是A,C,D三项分别是主体的一个方面,所以B项为正确答案.
　　2.C 事实判断题.根据是第二段第二句”In naked mole rat societies,…and perhaps age.”
　　3.D 实施引申题.根据是第二段内容及上下文.
　　4.A 细节题.根据是第一段第三句”…presumably,chemical control.”
　　5.D 细节理解题.根据是第三段第一句”…most cooperatively…are dominated by a pair of…”