A food web consists of all the food chains in a single ecosystem. Each living thing in an ecosystem is part of multiple food chains. Each food chain is one possible path that energy and nutrients may take as they move through the ecosystem. All of the interconnected and overlapping food chains in an ecosystem make up a food web.
It shows a direct transfer of energy between organisms. As every organism can feed on multiple things, a food web is a much more realistic and simplified method of transferring energy in an ecosystem. Both food chains and food webs, share three types of organisms in a food chain: producers, consumers, and decomposers.
Trophic Levels in a Food Web
- Primary Producers: Primary producers are a basic part of an ecosystem. They can be thought of as the first and most important step in the food chain. Primary producers are consumed by primary consumers, which are then consumed by secondary consumers, and so on. Organisms at the top of the chain eventually die and are then consumed by decomposers, which fix the nitrogen levels and provide the organic material necessary for the next generation of primary producers.
- Primary consumers: Primary consumers are herbivores, feeding on plants. Caterpillars, insects, grasshoppers, termites, and hummingbirds are all examples of primary consumers because they only eat autotrophs (plants). Certain primary consumers are called specialists because they only eat one type of producer. Ex: Rabbits, Beavers, Elephants, and moose.
- Secondary consumers: They are organisms that eat primary consumers for energy. Primary consumers are always herbivores or organisms that only eat autotrophic plants. However, secondary consumers can either be carnivores or omnivores. Carnivores only eat other animals, and omnivores eat both plant and animal matter.