Biotic succession is caused by

Options

A. Competition amongst species
B. Occurrence of diseases
C. Changes in grazing habits
D. Adaptive ability to environmental changes

Answer

**Step-by-Step Solution:**

1. **Understanding Biotic Succession**:
- Biotic succession, also known as ecological succession, refers to the process through which ecosystems change and develop over time. It involves a series of progressive changes in the composition of species in a given area.

2. **Identifying Causes of Biotic Succession**:
- To determine what causes biotic succession, we need to analyze the provided options. The options suggest various factors that could lead to changes in ecosystems.

3. **Evaluating Each Option**:
- **Option 1: Competition among species**: While competition can influence species distribution, it is not a primary cause of succession. It is more of a result of existing species interactions.
- **Option 2: Occurrence of diseases**: Diseases can affect populations but are not a fundamental cause of biotic succession.
- **Option 3: Changes in grazing habits**: Changes in grazing habits can impact certain species but do not directly initiate the process of succession.
- **Option 4: Adaptive ability to environmental changes**: This option suggests that the ability of organisms to adapt to changes in their environment is a significant driver of biotic succession. This is true as it allows species to survive and thrive in changing conditions, leading to a shift in community composition.

4. **Conclusion**:
- After evaluating all options, the correct answer is **Option 4: Adaptive ability to environmental changes**. This ability is crucial for the process of biotic succession as it allows organisms to respond to and survive in changing environments.

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