Competition occurs when

Options

A. closely related species compete for same resources
B. unrelated species compete for same resources
C. both 1 and 2
D. natural resources are unlimited

Answer

**Step-by-Step Solution:**

1. **Understanding Competition**: Competition in ecology refers to the struggle between organisms for limited resources such as food, water, space, and mates. This struggle can occur within a species (intraspecific competition) or between different species (interspecific competition).

2. **Identifying the Options**: The question provides four options regarding when competition occurs:
- A. Closely related species compete for the same resources.
- B. Unrelated species compete for the same resources.
- C. Both 1 & 2.
- D. Natural resources are limited.

3. **Analyzing Option A**: Closely related species often compete for the same resources due to similar needs. This is a common scenario in nature where species with similar ecological niches may overlap in resource usage.

4. **Analyzing Option B**: Competition can also occur between unrelated species. For example, different species may inhabit the same environment and compete for similar resources, such as food or nesting sites. The example of flamingos and fish competing for zooplankton illustrates this point.

5. **Considering Option C**: Since competition can occur between both closely related species and unrelated species for the same resources, this option suggests that both scenarios are valid.

6. **Analyzing Option D**: While limited resources can intensify competition, competition can occur regardless of resource availability. Therefore, this option alone does not fully encompass the conditions under which competition occurs.

7. **Conclusion**: Given that competition can arise between both closely related and unrelated species for the same resources, the most comprehensive answer is option C: both 1 & 2.

**Final Answer**: C. both 1 & 2.

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