Kin selection

How can individuals calculate relatedness? They generally don’t need to, any more than a bird needs to calculate aerodynamic forces to fly. If, under certain conditions, performing a behavior satisfies Hamilton’s rule, then the action is favored. The triggering conditions may include cues to relatedness, which are usually based on social experience. A bee, for example, learns the smell of her birth colony — where everyone is her relative — and uses that information for classifying unfamiliar individuals.