​Producers

​Producers, also known as autotrophs, make their own food. They make up the first level of every food chain. Autotrophs are usually plants or one-celled organisms. Nearly all autotrophs use a process called photosynthesis to create “food” (a nutrient called glucose) from sunlight, carbon dioxide, and water.

​Primary Comsumers

​Primary consumers make up the second trophic level. They are also called herbivores. They eat primary producers—plants or algae—and nothing else. For example, a grasshopper living in the Everglades is a primary consumer

​Secondary Consumers

Secondary consumers are generally meat-eaters (carnivores). The organisms that eat the secondary consumers are called tertiary consumers. These are carnivore-eating carnivores, like eagles or big fish. Some food chains have additional levels, such as quaternary consumers (carnivores that eat tertiary consumers).

​Tertiary Consumers

​The organisms that eat the secondary consumers are called tertiary consumers. These are carnivore-eating carnivores, like eagles or big fish. Some food chains have additional levels, such as quaternary consumers—carnivores that eat tertiary consumers. Organisms at the very top of a food chain are called apex consumers.

Quaternary Consumers (final consumers)

​Quaternary consumers are often top predators within the environment, and they eat the tertiary consumers. Examples of quaternary consumers include lions, wolves, polar bears, humans, and hawks. Organisms may operate under different roles, such as a bear that eats fish but also berries

​Decomposers

​The group of organisms called decomposers forms the final link in the food chain. They break down dead animals and plants and return vital nutrients to the soil. Some decomposers, like fungi, can be seen without a microscope, but much of the decomposition process is carried out by microscopic bacteria