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Biology

Biological Altruism and the Evolution of Cooperative Behavior

Quick fact

In many ground squirrel species, an individual will give a loud alarm call to warn others of a predator, even though this call draws the predator’s attention to the caller and increases its own risk of being eaten.

Why this is interesting

You’ve probably heard that evolution is all about survival of the fittest, but how can an animal risk its own life to help another? Why would evolution ever allow such self-sacrifice?