Why do dogs care about their owners?

That's because they have been a gregarious and hierarchical animal since ancient times. The middle and lower levels strictly abide by discipline and listen to the leadership. The process of human domesticating them is the process of letting people replace their heads.

By sequencing the DNA of canines all over the world, it is hard to say how dogs evolved, because the ancestors of dogs are not one kind, but mixed-race descendants of gray wolves, jackals and foxes scattered everywhere. There is strong evidence that dogs were first domesticated in the Middle East10.6 million years ago, and domesticated dogs appeared in South Asia and East Asia10.4 million years ago.

As we know, agriculture appeared 1 10,000 years ago, so the intimate relationship between dogs and people did not originate from food.

The characteristics of these dogs mentioned just now are very different from the origin of cats. Cats all over the world have only one ancestor, and domestic cats appear because of agriculture.

But now DNA evidence shows that domesticated dogs, which appeared before the agricultural society, are now extinct. Those dogs are all carnivores. 7,000 years ago, a certain breed of dogs in Asia evolved the ability to digest starch, gradually replacing all dogs domesticated in the Paleolithic.

More vividly, this process is like this:

/kloc-One day 0/6000 years ago, human ancestors in the Middle East hunted all kinds of animals stronger and faster than themselves. Although they can't be said to be invincible, they still have some advantages compared with the wolves, tigers and leopards that competed with them at that time. These advantages were built with stone weapons and fire.

At that time, the bones left by the tribe were all thrown in one place and piled up. It is this smell that attracts the wolf closest to the crowd.

Wolf is an animal with very strong digestion and chewing ability. Only bones can be eaten well, so bold wolves often turn over human garbage at night when people are unprepared. The ancestors of human beings have strong teamwork ability. When the night watchman finds them, he will drive them away, but occasionally he will catch a few wolves before he can run. It doesn't eat normally, and it looks furry. It has big eyes and is quite cute, so I will stay.

Wolf is a socialized class animal. After being adopted by human beings as a child, they will spontaneously show obedience to others before adulthood. Young and ignorant little wolves treat people as wolves and leaders. After a long time, they can help with the vigil. When people can't hear those abnormal movements, they will first detect them, then call the police, and sometimes even rush out to drive away other carnivores lying in ambush.

However, at first, the little wolf brought back in this way was just at people's beck and call before he was fully grown up. As long as their wings are hard, they will try to challenge the authority of the people. This kind of behavior also exists in wolves, but it is usually severely taught by the strong wolves in the wolves, and then it will be honest.

However, when wolves living in human communities grow up, they may not be able to continue to integrate into human society. If they bite their children too much, the result may be being bitten to death.

If we don't go too far and just stop listening to people and complete the tasks entrusted to us by human beings, then we will never get food again, and they may return to the forest on the edge of human communities. However, it has been raised by people since childhood, and it is still very familiar with people's environment, so maybe there will be little wolves in the future, and it will continue to take them to the garbage to find food. These puppies are special puppies. They will imitate their mother's behavior and be less aggressive when they are caught again. According to this cycle, gradually, people also found that some wolves who came to pick up garbage near their homes were not so aggressive.

So the wolf chose not to attack or leave, while the man chose a more docile individual, and the two sides chose each other, so that the prototype of the dog appeared soon.

Juvenile continuation and * * * evolution

That won't take long. How long did it take?

Scientists from the former Soviet Union conducted an experiment for 40 years. They want to use wild foxes to restore the domestication of gray wolves into dogs.

In 1959, 130 silver foxes were brought into the experiment. They have frequent contact with people every day, and all kinds of training are designed for them to establish a trust relationship with people.

Then, pick out those individuals who show more affection and docility in training, then let them breed the next generation, and then cycle this process.

Foxes are very cautious animals when they are in the wild, but even so, after 35 generations, foxes have no appearance of foxes at all, and their body smells are gone. They will wag their tails happily when they meet the laboratory staff, lick people's faces actively, and act coquetry through poor whining, all of which look a bit like dogs. It is quite possible that this is how the gray wolf became a dog.

In the study of dogs, it is worth mentioning that this is also the biggest difference between dogs and wolves. The technical term is juvenile continuation.

What does this mean?

Is a species, it will always have some characteristics that only show in childhood, and once it becomes an adult, it will disappear completely.

Juvenile continuation refers to the change of environment or some problems of gene development, even if some individuals become adults, the characteristics of childhood will be very obvious and will not disappear.

For example, some men in their forties still have baby faces instead of angular beards and wrinkles, which is a continuation of infancy.

For the first dogs, they were all gray wolves in essence. As an adult, the gray wolf will naturally show aggression, trying to constantly challenge the wolf's status and have a crazy pursuit of food.

But these are unacceptable in human society, so in the evolution of dogs, all individuals who show the continuation of infancy will be left behind, because they are not aggressive, will not pose a threat to wolves, that is, their owners, and will not be so crazy about food. They are even childlike all their lives, and their noses are very sensitive, but as long as their owners don't point out where there is food, they usually look at their owners eagerly and wait for them to point out where the food is.

There are obvious differences between wolves and dogs in the laboratory, such as setting a device with pedals, which will drop a piece of meat when stepping on it. People show dogs first. When a piece of meat fell out, the dog ate it happily. Then the man stepped on another foot, another piece of meat fell out, and the dog ate happily again. But after that, people stopped stepping on it, but the dog wanted to eat meat. It just sat quietly and begged people to step on it again with eager eyes.

If the dog is replaced by an adult wolf in this experiment, it only needs to see how the device produces meat once, and then it steps on itself until it eats up the meat, regardless of people's opinions.

In childhood, wolves and dogs feel close to people, especially when people come back after walking for a few days. Dogs and wolves are extremely happy. But when they are adults, if people walk for a few days and come back, dogs will still jump into people's arms like when they were children, but wolves don't care much about this person who has disappeared for a few days. At this point, he has even chosen a new leader in his small community, and this leader will be hostile to the returning owner and even try to attack him.

This is the best example of a dog showing a continuation of infancy, while a wolf does not.

People domesticated the gray wolf into a dog, which affected the development mode of the dog and produced the characteristics of young continuation.

On the other hand, because of the appearance of dogs, people's quality of life has been greatly improved. Under the harsh conditions of primitive society, other species, also Homo sapiens, froze to death, but this branch of human beings survived. Here are some dogs, which can help people improve the success rate of hunting, improve the safety at rest and improve the productivity when grazing, like the environment in the Arctic Circle, if there are no Eskimo dogs.

So, in fact, people and dogs evolved in 16000. Sometimes we can even regard the primitive man with a team of dogs as a new species composed of two species, who evolved together in a mutually beneficial relationship, instead of always evolving together in a life-and-death competitive relationship like separate species.