题干

下列有关生物进化及物种形成的叙述不正确的是(  )

A:在一个种群中随机抽出一定数量的个体,其中基因型为AA的个体占24%,基因型为Aa的个体占72%,则基因A和基因a的频率分别是60%,40%

B:自然选择可以定向改变种群的基因频率,因此可以决定生物进化的方向

C:经过突变和基因重组、自然选择及隔离三个基本环节,能导致新物种的形成

D:突变和基因重组可以使种群产生定向变异,因而可能导致新物种的形成

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D

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    Most people agree that honesty is a goodthing. But does Mother Nature agree? Animals can't talk, but can they lie in other ways? Can they lie with their bodies and behavior? Animal experts may not call it lying, but they do agree that many animals, from birds to chimpanzees, behave dishonestly to fool other animals. Why? Dishonesty often helps them survive.

    Many kinds of birds are very successful at fooling other animals. For example, a bird called the plover sometimes pretends to be hurt in order to protect its young. When a predator(猎食动物)gets close to its nest, the plover leads the predator away from the nest. How? It pretends to have a broken wing. The predator follows the "hurt" adult, leaving the baby birds safe in the nest.

    Another kind of bird, the scrub jay, buries its food so it always has something to eat. Scrub jays are also thieves.They watch where others bury their food and steal it. But clever scrub jays seem to know when a thief is watching them. So they go back later, unbury the food, and bury it again somewhere else.

    Birds called cuckoos have found a way to have babies without doing much work. How? They don't make nests(鸟巢). Instead, they get into other birds' nests secretly. Then they lay their eggs and fly away. When the baby birds come out, their adoptive parents feed them.

    Chimpanzees, or chimps, can also be sneaky. After a fight, the losing chimp will give its hand to the other. When the winning chimp puts out its hand, too, the chimps are friendly again. But an animal expert once saw a losing chimp take the winner's hand and start fighting again.

    Chimps are sneaky in other ways, too. When chimps find food that they love, such as bananas, it is natural for them to cry out. Then other chimps come running. But some clever chimps learn to cryvery softly when they find food. That way, other chimps don't hear them,  and they don't need to share their food.

    As children, many of us learn the saying "You can't fool Mother Nature." But maybe you can't trust her,either.