The essence of Rivet Popper Hypothesis' is

Options

A. The current species extinction rates are estimated to be 100 to 1,000 times faster than in the pre-human times.
B. Species diversity decreases as we move away from the equator towards the poles.
C. Areas rich in endemic species might be sites of active speciation.
D. Loss of keystone species affects the functioning of ecosystem severely.

Answer

### Step-by-Step Solution:

1. **Understanding the Rivet Popper Hypothesis**:
- The Rivet Popper Hypothesis was proposed by scientist Paul Ehrlich. It compares an ecosystem to an airplane, which is made up of many rivets (species). Each rivet is essential for the proper functioning of the airplane.

2. **Analogy Explanation**:
- In this analogy, if a few rivets (species) pop out (go extinct), the airplane (ecosystem) can still function adequately. However, if too many rivets, especially critical ones, pop out, the airplane may fail to function properly.

3. **Implications for Ecosystems**:
- The hypothesis suggests that all species in an ecosystem contribute to its overall health and function. The loss of species (like the loss of rivets) can lead to a breakdown in ecosystem functions.

4. **Conclusion**:
- The essence of the Rivet Popper Hypothesis is that biodiversity is crucial for the stability and functioning of ecosystems. The extinction of species can severely impact ecosystem health, similar to how the loss of essential rivets can compromise an airplane's operation.

5. **Identifying the Correct Option**:
- Among the options provided, the statement that "loss of keystone species affects the functioning of ecosystems" aligns perfectly with the essence of the Rivet Popper Hypothesis, making it the correct answer.