Level of life
Ecosystem
A community of living things together with its physical environment, linked by flows of energy and nutrients.
Food chains and webs
Who eats whom in an ecosystem. Energy and nutrients pass from producers to the animals that eat them.Source: OpenStax, 2018Source: Paine, 1966
Also called food web, trophic levels.
Idea or model
How Food chains and webs connects
Food chains and webs is part of
Food chains and webs is involved in
Process
Energy flow
Energy enters most ecosystems as sunlight and is lost at each step up a food chain, which limits how many levels it can support.
Process
Trophic cascade
Effects that ripple down a food chain, as when predators hold herbivores in check and plants flourish.
Studied in
Your progress
Sources & further reading
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
Biology 2e (opens the original in a new tab)
OpenStax (2018). OpenStax, Rice University.
Free introductory college textbook.
TextbookEducationalLicence: CC BY-NC-SA 4.0 (linked, not reused)
Food web complexity and species diversity (opens the original in a new tab)
Paine RT (1966). The American Naturalist 100:65-75.
Removing a predatory sea star from rocky shores reduced the number of species present.
Historical paperPrimary research