noun, plural: primary consumers
A food chain is defined as a feeding hierarchy in which organisms in an ecosystem are grouped into trophic (nutritional) levels and are shown in a succession to represent the flow of food energy and the feeding relationships between them. It is comprised of various trophic levels. A trophic level refers to a level or a position in a food chain or ecological pyramid. It is occupied by a group of organisms that have a similar feeding mode. In a food chain, there are three fundamental ways through which organisms obtain nourishment. These are by obtaining food from inorganic sources, by feeding organic matter, and by breaking down dead organic material or wastes. Those that are capable of directly obtaining food from inorganic sources are called producers (or autotrophs). Those that feed on organic matter are called consumers (or heterotrophs). Those that break down dead organic material are referred to as decomposers (or detritivores).
Consumers are organisms that generally obtain food by feeding on another organism or organic matter. They lack the ability to manufacture their own food from inorganic sources as what producers are capable of doing. In a food chain, consumers may be further grouped into primary consumers, secondary consumers, and tertiary consumers. Primary consumers are generally herbivores. They feed on producers. For instance, herbivores feeding on green plants are considered as primary consumers.
- first-level consumer