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Biology

Predator-Prey Dynamics and the Ecology of Fear in Terrestrial Ecosystems

Quick fact

Among Rocky Mountain elk, the presence of wolves was found to increase stress hormone levels in the elk, altering their behavior and habitat use. The effect of fear on prey can be as significant as the actual killing of prey in shaping populations and ecosystems.

Why this is interesting

In the wild, the mere presence of a predator can cause prey to change their behavior—even if they never get caught. How can a mountain lion that’s rarely seen still shape an entire forest ecosystem?