The Yellowstone National Park, which is located in the western part of the U.S., used to be a natural habitat for wolves. Unfortunately, there were no wolves living in the park back in 1926.

However, wolves have been spotted in the park somewhere between 1977 and the re-introduction in 1995. But, most of them were just transiting.

Now, after almost 70 years without these gorgeous animals, they were finally reintroduced in the Lamar Valley of the park in back 1995, the year when nature started changing.

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The impact of the wolves which were brought back to their natural habitat is more surprising than a person could have ever expected. They managed to transform the entire ecosystem of the Yellowstone National Park. In addition, they managed to change the course of the rivers.

Everything changed when the wolves started doing what they do best; hunt deer. The wolves reduced the deer population, which was destroying willows and aspens along the park’s waterways. Then, the vegetation at the park was brought back to life, it even made some other animals appear again.

For instance, trees started growing back and with them, beaves returned to build dams. The rivers in the park began to hold their course and there weren’t any erosions.

The park became a home for more rabbits and mice, who also attracted even more animals.

The amazing video below will show you the incredible way in which nature works. British writer George Monbiot is the narrator of the video. Although it was posted on YouTube back in 2014, it gained over 42 million views.

This story about wolves killing and frightening deers is one of the ecology’s most famous. However, there were other factors as well, such as human hunting, severe droughts, and bears who also helped to reduce the deer population.

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