Some people have done such an interesting experiment. They deliberately let a little orangutan alone see the workers burying grapes somewhere in the garden, and then put dozens of his companions in the park. When walking with his companions, the little orangutan who knows nothing happened. Three hours later, when his companions were asleep, he got up quietly, went to the "treasure-hiding place" in the dark, dug up the grapes unnoticed and ate them all. A zoologist stumbled upon a clever trick of lions foraging in the wild: four lionesses joined forces to attack. Two lionesses stood high on the hill, deliberately letting their prey know that there were lions here, and the road was blocked. The third lioness got into the grass and sneaked into the prey, and the fourth lioness roared out from the other direction, bluffing and trying to drive the panicked prey to the ambush grass. The frightened prey, surrounded on three sides, ran to the grass in a conditioned way, and the third lion grabbed the delicious food delivered to the door effortlessly. Is it accidental that lions have a tacit understanding? Someone once put three small plates in front of the phoenix-headed maiji, one of which put a bug, another put two, and another put three. As a result, it sometimes eats two first, and sometimes it eats three first. This experiment shows that the crested pheasant knows the difference between large quantity and small quantity. It has also been found that when crows see hunters with guns, they will hide at the top of trees and dare not fly down again. So, four hunters hid in the hut in front of the crow. Later, a hunter walked away, but the crow didn't fly down; Two hunters walked away, but the crow still didn't fly down; However, after three hunters were gone, the crow thought that all the hunters had gone and flew down. This shows that crows are smarter than chickens, and they can "count" to 3. Foreign scientists have put four identical boxes in front of pigeons, with one point, two points, three points and four points painted on the lids. In the experiment, only four boxes were filled with food, and the pigeon got the food. In the later experiments, it always opened the four boxes first. Thus, pigeons can "count" to 4. Gray squirrel will hide pinecones in many places before winter. After that, it can usually only find six or seven piles, and the rest will not be looked for. This shows that maybe the squirrel can only "count" to seven. There is a chimpanzee who eats 1 bananas from a box at a time. Once, the scientist put eight bananas in the box. After the chimpanzee finished eating, he continued to look in the box. The scientist gave him another banana, but he still refused to go away. He would not leave until he had eaten 1 bananas. There is a hound that has been scratching its owner with its paws 45 minutes before his seizure for more than a year, giving his owner Ramsey enough time to move to a safe place before the seizure. The latest research shows that birds have two kinds of magnetic field sensing systems. One seems to be equivalent to converting polarized light into visible light, thus acting as a compass. The other is a magnet-like system in birds for further orientation. Dolphins can quickly find a softball-sized object far away from two football fields in turbid seawater, thanks to its advanced sonar system. At present, artificial machines still can't reach the extraordinary ability of dolphins.