Which of the following will relate to vertical distribution of different species occupying different levels of ecosystem ?

Options

A. Physiognomy
B. Pyramid of numbers
C. Stratification
D. Succession

Answer

To solve the question regarding the vertical distribution of different species occupying different levels of an ecosystem, we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which term relates specifically to the vertical distribution of different species in an ecosystem. This means we are looking for a concept that describes how various species are arranged at different heights or layers within an ecosystem.

2. **Analyzing the Options**:
- **Option A: Physiognomy**: This term refers to the external appearance of a community, including its structure and form. While it provides information about the community, it does not specifically address vertical distribution.

- **Option B: Pyramid of Numbers**: This concept involves a graphical representation of the number of organisms at each trophic level in an ecosystem. It shows the relationship between different levels but does not focus on vertical distribution of species in terms of their layers or heights.

- **Option C: Stratification**: This term specifically refers to the vertical distribution of different species occupying different levels in an ecosystem. It describes how various species are layered in a habitat, such as in forests where different plants and animals occupy different heights.

- **Option D: Succession**: Ecological succession is the process of change in the species structure of an ecological community over time. While it involves changes in species composition, it does not specifically relate to their vertical distribution at a given time.

3. **Identifying the Correct Answer**: After analyzing all the options, it is clear that **stratification** (Option C) is the term that directly relates to the vertical distribution of different species occupying different levels of an ecosystem.

### Conclusion:
The correct answer is **stratification**.

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