Consumers, Ecological

The term ECOLOGICAL CONSUMERS refers to species that cannot produce their own food, and so get energy and nutrients by eating other organisms. Properly termed heterotrophs, they are distinguished from autotrophs, or producers, that produce their own food via photosynthesis (plants and cyanobacteria) and chemosynthesis (carried out by bacteria near deep ocean hydrothermal vents). Consumers occupy the highest levels of the trophic hierarchy, a system of classification in which species are grouped according to their position in food chains and webs. Other levels of the trophic hierarchy involve the conversion of energy (solar and heat), gases and inorganic gases into biotic carbohydrates and proteins (via producers), and back into the abiotic components (via decomposers, such as fungi), whereas consumers strictly cycle biotic compounds and energy.

Consumers ...