Explain the reson for the richness of biodiversity in the tropics?

Explanation

The reasons for the richness of biodiversity in the tropics are:
(i) The warm tropical region on either side of equator provide congenial habitat for living organisms.
(ii) Environmental conditions in the tropics are conducive for speciation as well as for supporting both variety and number of organisms.
(iii) The temperature in the tropic ranges between `25^(@)C and 35^(@)C`, which are ideal for most of the metabolic activities of organisms.
(iv) The average rainfall is more than 200 mm per year, which is sufficient to support the whole ecosystem.
(v) Rich resource and nutrient availability to support the functions of ecosystem.
(vi) Climate, seasons, temperature, humidity, photo period etc., are more or less stable and encourage both variety and number.