UPSC Prelims 2012 · GS Paper I
Question 96: Environment and Ecology
Which of the following can be threats to the biodiversity of a geographical area?
- 1.Global warming
- 2.Fragmentation of habitat
- 3.Invasion of alien species
- 4.Promotion of vegetarianism
Select the correct answer using the codes given below :
AnswerUPSC’s answer is (a).
Threats to biodiversity include global warming (climates shifting faster than species can adapt), habitat fragmentation (isolating populations) and invasion by alien species that outcompete natives. Promoting vegetarianism is a food choice and not a recognised threat to biodiversity. Other major threats are habitat loss, overexploitation and pollution.
- 1. Global warming changes habitats faster than species adapt.
- 2. Fragmentation isolates populations and shrinks habitat.
- 3. Alien species can outcompete and displace natives.
- 4. Promoting vegetarianism is not a recognised biodiversity threat.
How you could have got this
- If you were sure statement 1 is correct, (b) goes: it leaves 1 out.
What you needed to know: Global warming changes habitats faster than species adapt.
- Then, if you were sure statement 4 is not correct, (c) and (d) go: each of them includes 4.
What you needed to know: Promoting vegetarianism is not a recognised biodiversity threat.
Only (a) is left. You didn’t need statements 2 or 3.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Correct: global warming, habitat fragmentation and alien species.
- (b) Incomplete: global warming is also a threat.
- (c) Wrong: vegetarianism is not a threat, and it leaves out fragmentation and alien species.
- (d) Wrong: statement 4 on vegetarianism is not a threat.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2012, General Studies Paper I, Series A. The paper on upsc.gov.in.