📘 Q.4 IAS Prelims 2023 — Environment & Ecology (Nocturnal Fauna)🧷 Authentic Classroom Explanation by IAS Monk
📌 The Question
Consider the following fauna:
- Lion-tailed Macaque
- Malabar Civet
- Sambar Deer
How many of the above are generally nocturnal or most active after sunset?
(a) Only one
(b) Only two
(c) All three
(d) None
✅ Correct Answer: (b) Only two
🧑🏫 Classroom Explanation
Fauna-wise analysis:
🔹 1. Lion-tailed Macaque ❌
- A diurnal primate
- Active during daylight hours
- Lives in the upper canopy of tropical evergreen forests
➡️ Not nocturnal
🔹 2. Malabar Civet ✅
- Strictly nocturnal and extremely elusive
- Rarely sighted; activity peaks at night
➡️ Nocturnal
🔹 3. Sambar Deer ✅
- Crepuscular to nocturnal
- Most active during dusk, night, and early dawn
➡️ Counts as nocturnal/after sunset
✔️ Hence, 2 out of 3 are nocturnal or active after sunset.
⚡ Curiosity Raiser
Why does UPSC club civets and deer with primates?
👉 To test whether you distinguish activity patterns, not habitats.
📚 Enrich Notes (UPSC Edge)
- Diurnal: Active during daytime (e.g., monkeys, squirrels)
- Nocturnal: Active at night (e.g., civets, owls, bats)
- Crepuscular: Active at dawn & dusk (e.g., deer, cats)
🧠 UPSC often treats “crepuscular” as functionally nocturnal in MCQs.
🕊️ IAS Monk Whisper
“In the forest, survival depends not just on where you live — but when you live.”