UPSC Prelims 2023 CSAT Paper II · Q23 of 77 Comprehension medium

Passage

Passage – 3 Elephants are landscape architects, creating clearings in the forest, preventing overgrowth of certain plant species and allowing space for the regeneration of others, which in turn provide sustenance to other herbivorous animals. Elephants eat plants, fruits and seeds, propagating the seeds when they defecate in other places as they travel. Elephant dung provides nourishment to plants and animals and acts as a breeding ground for insects. In times of drought, they access water by digging holes which benefits other wildlife.

Which one of the following statements best reflects the most logical and rational inference that can be drawn from the passage ?

  1. (a) The home range of elephants needs to be a vast area of rich biodiversity.
  2. (b) Elephants are the keystone species and they benefit the biodiversity. ✓ UPSC's answer
  3. (c) Rich biodiversity cannot be maintained in the forests without the presence of elephants.
  4. (d) Elephants are capable of regenerating forests with species as per their requirement.

Why the answer is (b)

• The passage describes elephants as 'landscape architects' who create clearings, prevent overgrowth, and allow regeneration of other plant species.

• It highlights that elephants propagate seeds through defecation, provide nourishment via dung, and dig water holes during droughts that benefit other wildlife.

• These actions demonstrate that elephants play a critical role in maintaining the ecosystem structure and supporting other species, which is the definition of a keystone species.

• The cumulative effect of these behaviors is the sustenance of other herbivores and the general health of the forest ecosystem, directly linking elephants to the benefit of biodiversity.

• Therefore, the most logical inference is that elephants are keystone species whose activities actively benefit and sustain biodiversity.

Why the other options are wrong

(a) The home range of elephants needs to be a vast area of rich biodiversity.
The passage does not specify the size of the home range or explicitly state that it must be a 'vast area' of rich biodiversity, only that they travel and create clearings.
(c) Rich biodiversity cannot be maintained in the forests without the presence of elephants.
The statement is too absolute; the passage says elephants help maintain biodiversity but does not claim that rich biodiversity *cannot* be maintained without them.
(d) Elephants are capable of regenerating forests with species as per their requirement.
The passage states elephants allow space for regeneration of *other* species and propagate seeds, but does not suggest they regenerate forests based on their own specific requirements.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2023, held on 28 May 2023. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

Reading the answer is not the same as getting it right under a clock. Practise this question with UPSC's negative marking, and anything you miss goes into an error notebook until you get it right twice.

Practise this paper free