Prelims 2013 · archive
EasyWhich one of the following terms describes not only the physical space occupied by an organism but also its functional role in the community of organisms?
Answer & explanation
Answer: (b) Ecological niche
An ecological niche covers both the physical space a species occupies and the role it plays in its community. A habitat describes only the place where the organism lives.
- ✗ (a) An ecotone is a transition zone between two ecological communities, such as a forest–grassland edge. It describes a boundary area, not an organism's role.
- ✓ (b) The niche combines where an organism lives with what it does: its food, its interactions with other species, and its position in the flow of energy. In the words of the FAO glossary, the habitat is the organism's address and the ecological niche is its profession.
- ✗ (c) Habitat is only the place or type of site where a species normally lives, such as a desert, lake or forest. It says nothing about the species' functional role. This is the most tempting wrong option.
- ✗ (d) Home range is the area an individual animal regularly moves around in for food, mating and shelter. It is a spatial idea and does not describe the organism's role in the community.
Remember · Habitat is an organism's address; niche is its profession. Niche = physical space plus functional role in the community.
Sources
- FAO Term Portal – ecological niche (definition from FAO Glossary of Aquaculture, 2008) ↗ “The habitat is the organisms’ address, and the ecological niche its profession, biologically speaking.”
- FAO – Glossary (Habitat) ↗ “The place or type of site where species and communities normally live or grow, usually characterized by relatively uniform physical features or by consistent plant forms”
Question: UPSC Civil Services (Preliminary) 2013, General Studies paper. Explanation: Minimalist IAS, checked 25 Oct 2026 (how we verify). ·