Fig. 1

Tropical regions of the world. Within each region , countries that lie entirely within the tropics are coloured a darker shade while those lying partially within the tropics are coloured a lighter shade. A minimum of 15% of a country’s landmass lying within the tropical zone was set as a requirement for it to be considered tropical. The tropics are estimated to contain 43% of the world’s population , 80% of the worlds biodiversity and 85% of the poorest people [1].