In 1995, the US Office of fish and wildlife, along with several Canadian biologists, captured 14 wolves from nature in Canada.
Than they released them in the national park “Yellowstone”, where they have been extinct since 1926.
Over the next 5 years, the number of wolves has increased, but it was actually the smallest change that has happened to “Yellowstone”.
The effects were better than anyone could have imagined. The entire ecosystem of the national park had changed so much that even the rivers have changed.
How is this possible?