Dolphins are smarter animals in the sea. Researchers put sea animals to a test. In the test, the researchers made red marks on the animal's bodies and took them in front of a mirror. Many sea animals either ran away or fought with the ones in the mirror. However, when the dolphins saw themselves in the mirror, they tried to clean the red marks off their bodies. So the researchers believed that the dolphins knew the ones in the mirror were just themselves.

    Bees work hard, and they are smart enough to learn something. Researchers found a group of bees and taught them to tell which horizontal line (水平线) was higher than the other. If they could find the higher line, they would get sugar as a prize. After training for a period of time, the researchers tested the bees. To their surprise, the bees found the higher horizontal line quickly and got sugar. Instead, when the researchers showed them vertical lines (垂直线), the bees simply flew away, because they knew there was no way to get sugar.

    Chimpanzees (黑猩猩) are very human-like. They can learn fast and well. Researchers showed the numbers from one to nine on the screen. Chimpanzees and some college students were asked to remember where the numbers were after watching the numbers in less than a second. The adult chimpanzees and the college students performed almost the same, but the young chimpanzees performed much better. It was amazing.