If every living thing is comfortably placed in nature and allowed to grow and multiply at leisure, the earth would soon become inadequate for life! Therefore, the equilibrium of life on earth should be kept in check. Food chains play that vital role in our environment.
Every living thing, at one or other time, is consumed by another. The process of who eats whom is called food chain. It is basically, a series of living beings linked together because each one is the food for another. The position each species occupies within a food chain is called a feeding level. Thus, plants come to the first as they represent the lowest level. The final consumer comes at the last level. Thus a pyramid is formed in the biosphere.
For example, grasshoppers eat plants; meanwhile, grasshoppers become prey to frogs. Snakes consume frogs. However, snakes are eaten by peacocks, which is the final consumer in the pyramid. When the final consumer at the top of the pyramid dies and disintegrates, its substances are taken up as nourishment by plants. Thus this chain or cycle continues. If any of the links is lost or damaged it affects the whole chain. All living beings are inter-connected and inter-dependent; and therefore, all living things are part of this chain.
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