The interaction between smaller barnacle Chthamalus and larger barnacle Balanus in intertidal zone is -

Options

A. Mutualism
B. Competition
C. Parasitism
D. Amensalism

Answer

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question refers to two types of barnacles: Chthamalus (the smaller barnacle) and Balanus (the larger barnacle).

2. **Understand the Habitat**: Both barnacles are found in the intertidal zone, which is the area that is above water at low tide and underwater at high tide.

3. **Review Connell's Experiment**: The interaction between these two barnacle species was studied by ecologist Joseph Connell. He conducted field experiments to observe their behavior and competition in the intertidal zone.

4. **Analyze Competition**: In Connell's experiments, it was observed that Balanus, being larger and more dominant, outcompeted Chthamalus for space on the rocks in the intertidal zone.

5. **Outcome of Interaction**: As a result of this competition, Chthamalus was often eradicated from the area where Balanus was present. This indicates that Balanus had a competitive advantage over Chthamalus.

6. **Conclusion**: The interaction between Chthamalus and Balanus in the intertidal zone is characterized as competition, specifically interspecific competition, where two different species compete for the same resources (in this case, space).

**Final Answer**: The interaction between smaller barnacle Chthamalus and larger barnacle Balanus in the intertidal zone is competition.

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