24. The main topic of the passage is the ____.

　　A) value of allelomimetic behavior in vertebrate and invertebrate species

　　B) definition and distribution of allelomimetic behavior

　　C) relationship of allelomimetic behavior to the survival of the fittest D) personality factors that determine when an individual animal will show allelomimetic behavior

　　25. Which of the following places is the most likely setting for allelomimetic behavior?

　　A) A lake.

　　B) A cave.

　　C) An underground tunnel.

　　D) A thick forest.

　　26. The author implies that allelomimetic behavior occurs most often among a nimals that ____.

　　A) prey on other animals

　　B) are less intelligent than their enemies

　　C) move in groups

　　D) have one sense organ that dominates perception

　　27. Which of the following is the most clear example of allelomimetic?

　　A) Bears hunting for carnivores.

　　B) Cattle fleeing from a fire.

　　C) Horses running at a racetrack.

　　D) Dogs working with police officers.

　　28. According to the passage the primary function of allelomimetic behavior in bird is to ____.

　　A) defend nests against predators

　　B) look at each other

　　C) locate prey

　　D) warn against predators

　　29. According to the passage, what happens to the behavior of rodents when they are artificially crowded together?

　　A) Their allelomimetic behavior increases.

　　B) Continuous cooperation between them is maintained.

　　C) They become aggressive and attack each other.

　　D) They show little allelomimetic behavior.

　　30. Which of the following groups of human beings would probably show the greatest amount of allelomimetic behavior?

　　A) A group of students taking a test.

　　B) Tennis players competing in a tournament.

　　C) A patrol of soldiers scouting for the enemy.

　　D) Drivers waiting for a traffic light to change.

　　Questions 31 to 35 are based on the following passage:

　　The American Heart Association and other groups have said for many years that people could reduce the chance of suffering a heart attack by eating less of the foods rich in cholesterol(胆固醇). These include such foods as meats, milk products and eggs. The Heart Association noted a number of studies which show that nations where people eat a lot of high cholesterol foods have a higher number of deaths from heart disease. However, the new report disagrees. It was made by the Food and Nutrition Board of the United States National Academy of Sciences. The new report by a team of 15 scientists said there is no evidence to link cholesterol in food directly to heart disease. It noted seven major studies involving people whose diet was changed to include only foods low in cholesterol. The studies found only a very small reduction in the number of heart attacks and there was no reduction in the number of heart attack deaths. Other studies have shown similar results. They found that a change to low cholesterol foods will have only a minor effect on the amount of cholesterol in a person's blood and only a minor effect on the number of deaths. Medical scientists hope that two huge new studies may settle the cholesterol dispute. The tests are designed to learn if low cholesterol foods or anticholesterol drugs, or both, can reduce the amount of the substance in the blood and reduce the chance of a heart attack. The two new studies will be finished in the next year or two. The new Academy of Sciences report also discussed other possible links between food and disease. The scientists, in general, they are deeply concerned about some of the recent advice given about food. They noted that a number of private groups, government agencies and several popular books have advised that people can prevent heart disease, cancer and other sicknesses by changing the kinds of foods they eat. The new report said there is often no good scientific evidence to support such advice. In fact, the scientists said such ideas often produce only false hopes or unnecessary fears.