In a stable ecosystem, the population of a herbivore suddenly decreases due to disease. Which of the following is the most likely immediate effect on the population of its plant food source?

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Question

In a stable ecosystem, the population of a herbivore suddenly decreases due to disease. Which of the following is the most likely immediate effect on the population of its plant food source?

Accepted Answer

The plant population increases because less grazing pressure is exerted on it — With fewer herbivores grazing on the plants, the plants experience less predation pressure and their population is likely to increase. Option A incorrectly links herbivore decline to reduced seed dispersal as the primary effect. Option B is wrong because herbivore grazing directly controls plant population size. Option D is incorrect because herbivore decline would not immediately reduce decomposer activity in a way that harms plants.

Answer

The plant population decreases because fewer herbivores disperse its seeds

Answer

The plant population remains unchanged because plants are unaffected by animals

Answer

The plant population decreases because decomposer activity is reduced

Answer

The plant population increases because less grazing pressure is exerted on it

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