Food Webs (or Food Chains)

Food webs are depictions of the feeding relationships that exist among species within an ecosystem, indicating flows of energy and biomass between trophic levels. Although a food web is a more complex conception than a linear food chain, it remains a relatively static and binary depiction: species either interact or they don't. Despite these limitations, food webs are useful conceptual tools, providing insights into the organization of communities and the interactions among different species within them.

Food webs are organized into trophic (or feeding) levels. Species are categorized as either producers or consumers. Producers or autotrophs, literally “selffeeders,” constitute the first trophic level—those species that synthesize their own food through processes of photosynthesis or chemosynthesis and includes most plants, algae, phytoplankton, and some species of bacteria. ...