(a) Why is the problem of predation more severe in plants than in animals ?
(b) List two important defence mechanisms plants have developed against herbivory ?
- As plants are anchored to soil, they cannot run away from their predators, namely the herbivores. Hence the problem of predation is more severe in plants than in animals.
- Plants do not mutely tolerate predation by herbivores. Many of them have developed defense mechanisms to keep away the animals which eat them. Some of these features are:
- Structural defenses - Certain structures on the body of the plants such as spines, trichomes, thick cuticle, sand or needle-like particles inside the body tissues, discourage the herbivores from consuming them.
- Chemical defenses - Plants produce and store chemicals which adversely affect the herbivores by making them sick, interfere with their digestive process, or directly killing them, as seen in Calotropis which produces a poisonous glycoside that acts as a cardiac poison. Chemicals such as nicotine, opium, quinine, strychnine are all deadly poisons produced by plants against herbivores.