Question

Arrange the following stages of ecological succession in the correct sequence
A. Ecesis
B. Nudation
C. Aggregation
D. Reaction
Choose the most appropriate answer from the options given below:

• A. A, B, C, D
• B. A, C, B, D
• C. B, A, C, D
• D. C, B, D, A

Hint:

Remember the succession sequence as a story of colonization:

\textbf{Bare land} (Nudation)
\textbf{First settlers arrive and establish} (Ecesis)
\textbf{Settlers multiply and form a village} (Aggregation)
\textbf{The village changes the landscape} (Reaction)

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Ecological succession is the process of change in the species structure of an ecological community over time. It follows a predictable sequence of stages.

Step 2: Detailed Explanation of the Sequence:
1. B. Nudation: This is the first step. It is the development of a bare area, completely devoid of life, due to factors like volcanic eruption, landslides, fire, or flooding.
2. A. Ecesis: This is the successful establishment of a species in a new area. It involves the germination of propagules (like seeds or spores), growth, and survival of the pioneer species that have migrated to the bare site.
3. C. Aggregation: Following successful establishment (ecesis), the individuals of the pioneer species reproduce and increase in number, forming groups or aggregations.
4. D. Reaction: As the pioneer species grow and aggregate, they begin to alter the environment. This is called reaction. They change soil composition, light availability, and moisture levels. This alteration makes the environment less suitable for themselves but more suitable for other, more competitive species to invade.

Step 3: Final Answer:
The correct chronological order of the stages of succession is Nudation \(\rightarrow\) Ecesis \(\rightarrow\) Aggregation \(\rightarrow\) Reaction. This corresponds to the sequence B, A, C, D. Therefore, option (C) is correct.