Class 12th Biology 2014 Set1 Delhi Board Paper Solution
Apart from being a part of the food chain, predators play other important roles. Mention any two such roles supported by examples.
Predators play an important role in:
1.Maintaining the prey population; this regulates intra-species competition. This also helps in checking any overgrazing by herbivores, which might ultimately lead to an unbalanced ecosystem. For example, if tigers are removed from a forest, spotted deer will multiply rapidly. This would result in rapid destruction of herbs and grasses in the forest and ultimately the whole forest.
2. Indicating ecological disturbances. Usually predators are small in number and highly sensitive to ecological changes, owing to their excessive adaptation. For example, Gharials are extremely adapted to their freshwater habitat. They start dying rapidly and in large numbers as soon as a river starts getting polluted, thus indicating ecological disturbances.
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