Wolves are considered a threat to other animals, especially pets, which is why we have almost wiped out the wolves, but now experts at Yellowstone National Park in the US state of Wyoming have learned something about wolves. There are revelations that you will be amazed at the usefulness of wolves and the system of nature. A video posted on the Sustainable Human Facebook page reveals the astonishing results of the park's research. The video states that wolves had disappeared from the park and not a single wolf remained in the park for 70 years. A few decades ago, a few wolves were brought back to the park and their arrival had such a positive effect on the condition of animals, birds, trees, herbs and even rivers and streams in the park that even experts were stunned. 
The wolves were not kept in the park for so long because they were a threat to the deer there, but when the wolves were brought back, they hunted a few deer, but their return benefited them far more. Due to their fear, deer and some other species of animals were confined to a few areas, which led to rapid growth of greenery in the rest of the park. Surprisingly, in a few years, the length of trees in these areas has increased significantly. There were trees everywhere. As a result, dozens of new species of birds came and settled in the park.
The wolves killed some of the venomous species, which multiplied the number of rats, rabbits and other such animals. The most surprising thing about the arrival of wolves was that the attitudes of the rivers and streams in the park also changed. As the number of greens and trees in the park increased, the rivers and streams, which had previously spread over a considerable area, began to overflow and leave much space on the banks.
In addition, the rivers remained almost non-flooding and they became very peaceful and in some places pools were formed in them which gave sanctuary to aquatic animals and their number began to increase. A few decades after a few wolves came to the park, the whole park map changed and it became clear that wolves are an integral part of our ecosystem, with dozens of them if we were to eradicate them. All kinds of trees, animals, birds and aquatic creatures will also become extinct.
