You will now listen to part of a lecture. You will then be asked a question about it. After you hear the question, you will have 20 seconds to prepare your response and 60 seconds to speak.
Question: Using points and examples from the talk, explain the two approaches host birds use to prevent other birds from laying eggs in their nests.
【正确答案】The lecture offers two examples of defenses birds use to prevent other birds from laying eggs in their nest.
The first is to alter their habits. Some species like the robin do not usually pay much attention to their own nests. But when other birds are seen lurking nearby, the robins become very watchful. In other words, robins change their habits and always look after their nest when noticing other birds nearby and thus prevent other birds from laying their eggs in the nest.
The other defense mentioned is for some species simply to reject or throw away any egg in the nest that is of a different size, shape, or color from its own. For example, American coots can recognize their own eggs and distinguish and push unfamiliar-looking eggs out of their nests. In this way, other birds have no chance to lay their eggs in the nest of host birds.
【答案解析】 该讲座介绍了鸟类防止其他鸟在自己巢中产蛋的两个例子。直接找出核心内容,在文章的第一段中:Naturally, where this sort of behavior is common,other species have developed detenses.Let’s consider two of these.