The entire sequence of communities that successively change in a given area are called:

Question

UnlockIAS · Accepted Answer

Correct — B, Sere. A sere is the whole series of communities that replace one another at one site — from the pioneer community on a bare substrate, through the intermediate (seral) communities, up to the climax community. Note the exact wording of the stem: it asks for the name of the entire sequence of communities. That sequence is the sere; the process that drives it is ecological succession; the community sitting at the end of it is the climax.

Why the other options are wrong — (a) This is the tempting near-miss. Succession is the process — the orderly, directional change by which one community replaces another over time. The sere is the product of that process: the actual series of communities. Succession is the verb, the sere is the noun.  (c) The climax is only the last stage of a sere — the relatively stable, self-perpetuating community in equilibrium with the local climate and soil. It is one community, not the whole sequence the question asks about.  (d) An evolutionary concept, not an ecological one: related lineages independently evolving similar features under similar selection pressures. It says nothing about communities replacing one another in a given area.

Concept: Ecological succession is the directional change in the species composition of a community at a place over time. The complete series of communities produced at that place is the sere; each community within it is a seral stage or seral community; the terminal, self-perpetuating stage is the climax community. Getting full marks on this family of questions is entirely a matter of keeping four words apart: succession (process), sere (whole series), seral stage (one link), climax (last link).

State PCS 2025 Q88 — Environment & Ecology PYQ with Answer

State PCS 2025 Q88 — Environment & Ecology PYQ with Answer