Animal Intelligence Are Animals intelligent? If they are, which animals are the most intelligent? These are not easy questions to answer. In the first place, no one is quite sure what intelligence is. We often say that intelligence means being able to solve problems.(46). For example, dogs and cats often find their way home from long distances. To do this they have to use their intelligence. They have to remember and think. But many birds find their way over long distances, too. They travel thousands of miles every year when they move from cool to warmer places. We do not know how they do this but we know that they do not use their intelligence. (47). Young birds are able to make these journeys without help as soon as they can fly. They are born with this ability. This is not intelligence. We call this 'instinct'. Often we cannot be sure whether an animal is acting intelligently or instinctively. When a dog hears a strange noise, it barks. This is instinct. It cannot stop itself from doing this. It does not really know why it is doing this. But supposing a house is on fire and the dog barks outside its master's bedroom until he wakes up, is the dog using its intelligence?(48). Often we cannot be sure. Many animals, however, can be taught to sole problems, especially when they are given rewards. Rats have been taught to press a lever to get food. Pigeons have been taught to peck a disc for the same reason. Even an octopus (章鱼) has been trained to know the difference between a square and an oblong (长方形) ! Animals in circuses have been taught to do all sorts of tricks to amuse an audience.(49). It is saying, ' if I do this, I will get a reward. Therefore I will do it.' This may be thought of as a low kind of intelligence. Some animals, however, show a much higher kind of intelligence. They solve problems without any help. Chimpanzees, one of the ape family, are much more intelligent than other animals. A chimpanzee once did something even more intelligent. He did not have a stick. He had two short tubes. Neither of the tubes was long enough to reach the banana but one was wider than the other. He jammed the narrow tube inside the wider tube and in this way made one tube long enough to reach the banana(50). A Is it solving the problem by waking its master or is it simply barking instinctively because it is afraid?