Q. Assertion : There are 34 biodiversity hotspots in the world.
Reason : High level of species richness is a criteria for selection of a biodiversity hotspot.

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Solution:

Hot spots are areas with high density of biodiversity or megadiversity which are also the most threatened ones. Ecologically hot spots are determined by four factors.
(i) Number of species/species diversity.
(ii) Degree of endemism
(iii) Degree of threat to habitat due to its degradation and fragmentation.
(iv) Degree of exploitation.
Myers (1988) initially identified 12 hot spots. Today the number of hotspots identified by ecologists is 34 covering an area less than 2% of land surface with about 20% of human population living there.