Food Web

  • Food web refers to a group of inter-related food chains in a particular community. Under natural conditions, the linear arrangement of food chain hardly occurs & these remain indeed inter-connected with each other through through different types of organisms at different trophic level.
  • Simple food chains are very rare in nature. This is because each organism may obtain food from more than one tropic level. In other words, one organism forms food for more than one organisms of the higher trophic level.
  • Food webs are very important in maintaining equilibrium (homeostasis) of ecosystem.Example: In a grassland ecosystem
    1. Grass→Grasshopper→Hawk
    2. Grass→ Grasshopper → Lizard → Hawk
    3. Grass → Rabbit → Hawk
    4. Grass → Mouse → Hawk
    5. Grass → Mouse → Snake → Hawk
  • Signficance of food web: Food webs are very important in maintaining the stability of an ecosystem. For example, the deleterious growth of grasses is controlled by the herbivores, when one type of herbivores increase in number and control the vegetation.
    Similarly, when one type of herbivorous animal becomes extinct, the carnivore predating on this type may eat another type of herbivore.
Sr. No.Food chainFood web
1It is a straight single pathway throuhg, which food energy travels in an ecosystemIt consists of a number of food chain through which food energy passes in the ecosystem
2Members of higher trophic level fed upon a single type of organisms of lower trophic level.Member of higher trophic level can feed as a number of alternative organisms of the lower trophic level.
3Presence of separate and isolated food chains adds to the instability of the ecosystem.Presence of food web increase the stability of the ecosystem
4It does not add to the adaptability and competitiveness of the organisms.Food web increases adaptability and competitiveness of the organisms.