Three of the following criteria have contributed to the recognition of Western Ghats-Sri Lanka and Indo Burma regions as hotspots of biodiversity : 1. Species richness 2. Vegetation 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?

1. Conservation International defines biodiversity hotspots based on two primary criteria: high levels of endemism (irreplaceable species) and significant threat perception (habitat loss). 2. Criterion 1 (Species richness): While not explicitly one of the two primary defining criteria by Conservation International, areas high in endemism often also exhibit high overall species richness. It is a contributing factor often associated with hotspots like the Western Ghats-Sri Lanka and Indo-Burma regions. 3. Criterion 3 (Endemism): This is a core criterion. A region must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics. 4. Criterion 5 (Threat perception): This is the second core criterion. A hotspot must have lost at least 70% of its original habitat. 5. Criterion 2 (Vegetation density) is not a defining criterion; deserts can be hotspots. 6. Criterion 4 (Ethno-botanical importance) relates to human use of plants and is not a primary ecological criterion for hotspot definition. 7. Criterion 6 (Adaptation) is a general biological process and not specific to hotspot definition. Therefore, Species richness (contributing factor), Endemism (core criterion), and Threat perception (core criterion) are the relevant criteria.