Mention any two significant roles of predation plays in nature.

Explanation

(i) Many herbivores are predators. Cattles, Camels, Goats etc., frequently browse on the tender shoots of herbs, shrubs and trees. Generally annuals suffer more than the perennials. Grazing and browsing may cause remarkable changes in vegetation.
(ii) Many defense mechanisms are evolved to avoid their predations by plants. Examples : Caiotropis produces highly poisonous cardiacglycosides, Tobacco produces nicotine, coffee plants produce caffeine, Cinchona plant produces quinine. Thorns of Bougainvillea.spines of Opuntia, and latex of cacti also protect them from predators.