Question

Series of changes on previously barren area is
A. Sere
B. Climatic climax
C. Primary succession
D. Secondary succession

Answer 1

Hint: During succession, changes occur in species structure in the ecological community. The pioneer species start inhabiting a part of the land that was not previously occupied. Over time overcoming all environmental disturbances, a climax species inhabits the place after which minimum disturbances are observed.

Complete answer:
-Sere: Incorrect answer
While a stable climax community is being established in an ecosystem, intermediate stages are formed that are not stable and are affected by environmental disturbances. Depending on the location of the community, sere can be different types. For example, hydrosere is a community in water, lithosere is a community on a rock, halosere is a community in marshes, etc.
-Climatic climax: Incorrect Answer
In an ecological community when the populations of plants and animals coexist in balance with each other and with the environment, it is called a climax community. It is the final stage of succession and remains unchanged unless acted upon by human interference.
-Primary Succession: Correct Answer
When a barren rock or land is exposed for the colonization of species for the first time, primary succession occurs. This helps in the formation of new islands. Primary succession takes place in stages. Initially, bare rock or water body is recognized, pioneers inhabit followed by annual herbaceous species, perennial grasses and shrubs followed by trees.
-Secondary Succession: Incorrect answer
A climax community may be destroyed due to natural calamities or human intervention. In this environment when succession occurs again it is called secondary succession.

Hence, the correct answer is option (C).

Note: In an ecosystem for the species to coexist, they should occupy individual niches. Adaptation is a must. Natural Selection and mutations are other factors that help species adapt to the changing environment in an ecosystem.