Practice question

Predation transfers energy from a prey organism to a predator and generally increases the predator's survival or reproduction while reducing the prey's fitness, commonly through death. Its interaction signs are therefore (+,-), with the positive sign assigned to the predator and the negative sign to the prey. Reversing participant order would produce (-,+) without changing the biological relationship, so labels should always identify which species each sign represents. (-,-) characterizes competition, (+,+) mutualism, and (0,-) amensalism when the first participant is unaffected. Predation is an exploitative interaction because the consumer's gain is directly linked to the victim's loss. 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.