Wolves are among Yellowstone's most popular sights – so popular and so closely watched they can become accustomed to seeing ...

This top-down effect is technically known as a trophic cascade – a “domino effect throughout the ecological community,” as Pacific Wild puts it. As wolves hunt animals in the rung of the food chain ...

The recording starts with Amie Huguenard's nervous question about the bear's presence, followed by Timothy Treadwell's ...