Consider the following statements about the pyramid of numbers: 1. In a grassland ecosystem, the pyramid of numbers is upright. 2. In a forest ecosystem with large trees, the pyramid of numbers can be partially inverted. Which of the statements given above is/are correct?
- A1 only
- B2 only
- CBoth 1 and 2Correct
- DNeither 1 nor 2
Explanation
Correct. Grassland number pyramids are upright (many grasses, fewer herbivores, even fewer predators). In forests, one large tree can support thousands of insects, so the base of the number pyramid is narrower than the herbivore level, creating a partially inverted shape.
Why the other options are incorrect
- Option A
Statement 2 is also correct. A single large tree supports numerous herbivorous insects, so the producer level has fewer individuals than the primary consumer level.
- Option B
Statement 1 is also true. Grasslands have many grass plants, fewer grasshoppers, still fewer frogs, and so on — a classic upright pyramid.
- Option D
Both statements are well-established in basic ecology.