Scientists think that most animals can't see colours. The world is black and white to them.

To find out if dogs could see colours，scientists gave dogs food every time they played a certain piece of music.   The dog got ready to cat only when they heard this piece of music.   They did not get ready to eat when they heard other piece of music.

Then the scientists gave the dogs food every time they showed them a certain colour. The dogs got ready to eat when they saw this colour.   The scientists thenshowed the dogs another colour. Agtin the dogs got ready to eat.   The colours were all the same to them.

Colours are not all the same to the monkeys, however.   For example, if we put food in a red box and do this every day,a monkey will always go to the red box to get the food.   If we then put food in a blue box, the monkey won't go to it.

There are many national parks in Africa where you can go on safari (游猎). In the northeast of South Africa, there is a national park named Kruger National Park. It is about 20,000 square kilometers. Many kinds of plants and animals live in Kruger, including (包括) the famous “Big Five”. For hunters (猎人), these five animals were some of the most difficult and dangerous to catch. Many travelers think mainly about seeing the Big Five while on safari. But there are many other interesting, and much smaller animals, too.

Tanzania (坦桑尼亚) is another country with many parks where you can go on safari. The good place is Gombe Stream National Park in the west of the country. It has thick forests, ancient (古老的) trees, and beautiful lakes. When you go deep into the forest, you can sit to wait for some animals to come near. You’ll be glad to watch these animals playing, eating and communicating with each other.

Chobe National Park in the country Botswana (博兹瓦纳) is another popular place for safari. This park is home to one of the largest elephant groups in the world. You can see elephants face to face in this national park. When you go around the park and feel the thick grass moving, there may be elephants. Then you can see them nearer. They walk past you to look for food.