Given below are two statements:
Statement I: If a predator is too efficient and overexploits its prey, the prey might become extinct and, following it, the predator will also become extinct for lack of food.
Statement II: But for predators, prey species could achieve very low population densities and cause ecosystem instability.
In the light of the above statements, choose the most appropriate answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Statement I is correct but Statement II is incorrect.
Predators and prey limit each other. Predators keep prey numbers in check, and a predator in turn depends on its prey for food.
Statement I: If a predator is too efficient and overexploits its prey, the prey might become extinct and, following it, the predator will also become extinct for lack of food. — True. A predator that kills its prey too fast removes its own food supply. This is why predators in nature are called ‘prudent’.
Statement II: But for predators, prey species could achieve very low population densities and cause ecosystem instability. — False. Predators keep prey populations under control. Without predators, prey species could reach very high population densities, not low ones, and that is what makes the ecosystem unstable.
NCERT Extract:
Population Interactions – “… Besides acting as ‘conduits’ for energy transfer across trophic levels, predators play other important roles. They keep prey populations under control. But for predators, prey species could achieve very high population densities and cause ecosystem instability.”
Population Interactions – “… If a predator is too efficient and overexploits its prey, then the prey might become extinct and following it, the predator will also become extinct for lack of food. This is the reason why predators in nature are ‘prudent’.”