In '' rivet - popper hypothesis '' , the wing rivets are compared with

Options

A. dominant species
B. critical link species
C. rare species
D. key stone species

Answer

### Step-by-Step Solution:

1. **Understanding the Rivet-Popper Hypothesis**:
- The rivet-popper hypothesis was proposed by ecologist Paul Ehrlich. It compares an ecosystem to an airplane held together by rivets, where each rivet represents a species in the ecosystem.

2. **Identifying the Role of Rivets**:
- In this analogy, rivets are essential for the structural integrity of the airplane (ecosystem). Each rivet (species) contributes to the overall functioning and stability of the ecosystem.

3. **Impact of Removing Rivets**:
- If rivets are removed (species go extinct), initially, the airplane (ecosystem) may still function adequately. However, as more rivets are removed, the airplane becomes weaker, leading to potential failure.

4. **Key Concept of Keystone Species**:
- Among the rivets, some are more critical than others. The rivets that hold the wings of the airplane are analogous to keystone species. Keystone species are those whose impact on the ecosystem is disproportionately large relative to their abundance.

5. **Conclusion**:
- In the context of the rivet-popper hypothesis, the wings of the airplane are compared with keystone species. The loss of keystone species can lead to significant changes in the ecosystem, potentially causing it to collapse.

### Final Answer:
In the "rivet-popper hypothesis," the wing rivets are compared with **keystone species**.

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