With respect to the Western Hoolock Gibbons, which of the following statements is/are correct ? 1. A Sanctuary in North-east India is home to this ape species listed as Endangered in the International Union for Conservation of Nature (IUCN) Red List. 2. They have specialized brachiation and can easily swing between trees. 3. They possess a strong and heavy build like gorillas, yet are remarkably agile tree climbers. Select the answer using the code given below :
- (a) 1 only
- (b) 1 and 2 ✓ UPSC's answer
- (c) 2 and 3
- (d) 3 only
Why the answer is (b)
• The Western Hoolock Gibbon, India's only ape, is listed as Endangered on the IUCN Red List and is protected in the Hollongapar Gibbon Wildlife Sanctuary in Jorhat, Assam — statement 1 is correct.
• Gibbons are the 'lesser apes' and the most specialised brachiators: with very long arms and hook-like hands they swing arm-over-arm through the canopy at speed — statement 2 is correct.
• Statement 3 is wrong: gibbons are small, slender and light (6–8 kg), the opposite of the heavy build of gorillas; their agility comes precisely from being light.
• Hoolock gibbons are also monogamous, live in small family groups and are famous for their loud duet calls.
• Hence 1 and 2 only.
Why the other options are wrong
- (a) 1 only
- Statement 2 on brachiation is also correct.
- (c) 2 and 3
- Statement 3 is wrong: gibbons are light and slender, not heavy like gorillas.
- (d) 3 only
- Statement 3 is wrong and statements 1 and 2 are correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2026, held on 24 May 2026. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.