Q.51 Which organism’s species have greater diversity in the Western Ghats than the Eastern Ghats?
1. Mammals
2. Amphibians
3. Reptiles
4. Pisces
Western Ghats vs Eastern Ghats: Greatest Species Diversity
Amphibians exhibit greater species diversity in the Western Ghats compared to the Eastern Ghats, making option 2 correct.
Biodiversity Context
Western Ghats, a UNESCO hotspot, harbor exceptional endemism due to heavy rainfall and stable forests, unlike drier, fragmented Eastern Ghats.
This contrast drives higher diversity across taxa, especially moisture-dependent amphibians thriving in Western Ghats’ shola forests and streams.​
Eastern Ghats support fewer endemics overall from aridity and habitat discontinuity.​
Correct Answer: Option 2
Amphibians (2) show stark disparity: Western Ghats host ~179 species (65% endemic) vs Eastern Ghats’ far fewer (~60-70 total, lower endemism).​
| Taxon | Western Ghats Diversity | Eastern Ghats Diversity | Key Factor |
|---|---|---|---|
| Amphibians | 179 spp., 65% endemic ​ | ~60-70 spp., <40% endemic | Moisture gradients favor Western endemics ​ |
| Reptiles | 157 spp., 62% endemic | Comparable but lower endemism | Less disparity than amphibians ​ |
| Fishes (Pisces) | 219 spp., 53% endemic | High but river-dissected similarity | Aquatic overlap reduces gap ​ |
| Mammals | 31 threatened spp. | Fewer endemics overall | Large mammals span both ranges ​ |
Option Explanations
-
Option 1 (Mammals): Incorrect—mammals show moderate disparity; many species (e.g., tiger, elephant) occur across both ghats.​
-
Option 2 (Amphibians): Correct—extreme endemism in Western Ghats (e.g., caecilians, bush frogs) unmatched in East.
-
Option 3 (Reptiles): Incorrect—reptile diversity elevated in West but Eastern Ghats host unique snakes/lizards with closer totals.​
-
Option 4 (Pisces): Incorrect—fish diversity high in both due to shared river systems; Western edge only modestly higher.​
Western Ghats’ amphibian hotspot status underscores conservation priority for this climate-sensitive group.​


