Connell's field experiment illustrates

Options

A. Competitive release
B. Competitive exclusion
C. Interference of competition
D. Commensalism

Answer

**Step-by-Step Solution:**

1. **Understanding Connell's Field Experiment**: The experiment was conducted by ecologist Joseph Connell on the rocky coast of Scotland. It focused on two species of barnacles: Balanus (the larger, superior species) and Chthamalus (the smaller, inferior species).

2. **Observations Made**: Connell observed that Balanus barnacles occupied the lower intertidal zone, while Chthamalus barnacles were found in the upper intertidal zone. When both species were present, Balanus outcompeted Chthamalus for space in the lower zone.

3. **Conclusion Drawn**: The experiment demonstrated that the presence of the larger Balanus barnacles led to the exclusion of the smaller Chthamalus barnacles from the lower intertidal zone. This phenomenon is known as competitive exclusion, where one species outcompetes another for limited resources, leading to the latter's local extinction or displacement.

4. **Identifying the Correct Option**: Given the observations and conclusions from Connell's experiment, the correct answer to the question "Connell's field experiment illustrates" is competitive exclusion.

5. **Final Answer**: Therefore, the correct option is B: competitive exclusion.

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