Predators may or may not kill their prey prior to feeding on them, but the act of predation often results in the death of its prey and the eventual absorption of the prey's tissue through consumption. Thus predation is often, though not always, carnivory. Other categories of consumption are herbivory (eating parts of plants), mycophagy (eating parts of fungi) and detritivory, the consumption of dead organic material (detritus). All these consumption categories fall under the rubric of consumer-resource systems.