20．D 查找信息题.从第三段第二句和第四段最后一句得出. 第十组 A Can trees talk? Yes — but not in words. Scientists have reason to believe that trees do communicate with each other. Not long ago, researchers learned some surprising things. First a willow tree attacked in the woods by caterpillarschanged the chemistry of its leaves and made them taste so terrible that they got tired of the leaves and stopped eating them. Then even more astonishing, the tree sent out a special vapor—a signal causing its neighbors to change the chemistry of their own leaves and make them less tasty. Communication, of course, does not need to be in words. We can talk each other by smiling, raising our shoulders and moving our hands. We know that birds and animals use a whole vocabulary of songs, sounds, and movements. Bees dance their signals, flying in certain patterns that tell other bees where to find nectar for honey. So why shouldn’t trees have ways of sending messages? 【查看更多】
