From Newsweek.com:

A new book has revealed the fascinating story of how one male wolf pup in Yellowstone National Park rose from being the runt of one litter to the pack leader of another as an adult.

The book, authored by naturalist Rick McIntyre, follows the reintroduction of wolves into the park in 1995, told through the story of the pup, Wolf 8, and another animal known as 21, Psychology Today reported.

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