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 occurs when organisms vie for the same resources in an ecosystem. This can happen among individuals of the same species or different species.

2. **Types of Competition**:
- **Intraspecific Competition**: This type occurs when individuals of the same species compete for limited resources. For example, two dogs fighting over a bone is an example of intraspecific competition.
- **Interspecific Competition**: This occurs when individuals of different species compete for the same resource. For instance, two different species of birds competing for the same food source.

3. **Conditions for Competition**: Competition is likely to occur when resources are scarce. When resources are limited, organisms are more likely to interact directly as they compete for these resources.

4. **Evaluating Options**:
- **Option 1**: Closely related species compete for the same resource - This is a valid statement as it describes interspecific competition.
- **Option 2**: Unrelated species compete for the same resource - This is also valid and describes another aspect of interspecific competition.
- **Option 3**: Natural resources are unlimited - This statement is incorrect as it contradicts the premise of competition, which arises due to limited resources.
- **Option 4**: Both closely related and unrelated species can compete for the same resource - This statement is true and encompasses both types of competition.

5. **Conclusion**: Therefore, competition occurs when both closely related and unrelated species compete for the same limited resources. The correct answer is that competition occurs when there is a scarcity of resources leading to interactions between organisms.

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