Three of the following criteria have contributed to recognition of Western Ghats- Sri Lanka and Indo-Burma regions as hotspots of biodiversity : 1. Species richness 2. Vegetration density 3. Endemism 4. Ethno-botanical importance 5. Threat perception 6. Adaptation of flora and fauna to warm and humid conditions. Which three of the above are correct criteria in this context ?

The designation of biodiversity hotspots, including the Western Ghats-Sri Lanka and Indo-Burma regions, is based on specific quantitative criteria established by Norman Myers and Conservation International [2]. The primary criteria are: 1) Species richness, specifically containing at least 1,500 species of vascular plants [2]; 2) Endemism, meaning these species must be found nowhere else on Earth [1]; and 3) Threat perception, defined as having lost at least 70% of the original primary vegetation or habitat [2]. While factors like vegetation density, ethno-botanical importance, and climatic adaptations (warm and humid conditions) characterize these specific tropical regions, they are not formal global criteria for hotspot status [2]. Therefore, the correct combination of criteria contributing to their recognition is species richness (1), endemism (3), and threat perception (5).

Sources

1. [2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > BIodIversIty Hotspots. > p. 5
2. [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > Himalayas and east and south east Asia > p. 9