Practice question

Spite describes behavior that imposes a fitness cost on both the actor and the recipient, conventionally represented as a negative-negative interaction. Such behavior can evolve under restricted conditions, for example when harming a competitor indirectly benefits close relatives or when population structure converts an apparent direct cost into an inclusive-fitness advantage. Altruism differs because the actor pays a cost while the recipient gains. Cooperation and mutualism produce benefits for both participants, although the terms are used at different organizational levels and may involve varying dependence. The defining feature of spite is therefore the simultaneous direct harm to the individual performing the act and to its target. A careful interpretation retains the assumptions of the underlying model and avoids extending it beyond available evidence. Within those assumptions, the keyed concept gives the most consistent account of the biological pattern and its expected outcome. This interpretation follows ecological definitions based on effects on fitness, energy flow, behavior, and population performance. It also shows why superficially similar alternatives can represent different mechanisms once the direction of benefit, harm, or resource transfer is considered.