一、簡答題(10%)
       Every time we watch apes in their cages we are startled by their manlike behavior. The monkey house has a strange fascination. The visitors would be even more startled if they were fully aware of all the existing similarities between them and these animals. These include not only external behavior, but also all the organs, the whole skeleton, every single bone and tooth. The brain of a chimpanzee has the same internal structure and on its surface the same pattern of folds as the human brain, which, however, is three times as large. The way the mother chimpanzee nurses its young is not unlike that of the human mother. These and thousands of other features point to a blood relationship in the truest sense of the word. This can be clearly demonstrated by comparing the genes of chimpanzees and those of humans: the difference between them is just about 2 percent.