A food chain is a succession of living beings in which each one eats that which precedes it. The first link of a chain is very often a chlorophyllian plant. In the seas and oceans, the Phytoplancton ensures this role. In the abyssal depths where the rays of the Sun do not arrive, the thermophilous bacteria are the first chain links. However, in the abyssal depths, the photosynthetic chain exists all the same, indeed the organization pelagic die and run.

The man is often the last element of the chain: it is a Superprédateur.

In a ecosystem, the bonds which link the species are generally of a food nature. One distinguishes three categories of organizations:

• the producers (especially plants chlorophyllian, able, thanks to the Photosynthesis, to manufacture organic matter starting from carbon dioxide and of solar light, but also of other organizations Autotrophic S, some being at the base of food chains completely independent of solar energy.)

• the consumers (animals); there exist three types of consumers:
• the Herbivore S which nourish producers, one calls them also consuming primary educations
• the Carnivore S primary educations or consuming secondaries which nourish herbivores
• the carnivorous secondaries called also consuming tertiary sectors which nourish primary education carnivores
• the décomposeurs (the Bactérie S, Champignon S) who degrade the organic matters of all the categories and restore in the medium the biogenic salts.

These relations form sequences where each individual eats the precedent and is eaten by that which follows it; one speaks about food chain . Each link is a trophic Niveau. The ecological Niche is what two animal species divide when they live the same medium and that they have same the food Régime. Thus, two species having the same niche are in “competition”.

See too

• Agroalimentary
• Food safety

Simple: Food chain