Anung97 writes: RL: “A small and compact body easily diffuses heat in a very hot environment. A large or tall body will not diffuse heat well and may well overheat in that environment.” If this is the case how come Sub Saharan Africans are tall and big? Shouldn’t they be small like us Indonesians? Or maybe they compensate by sweating a lot?
Not sure, but Blacks are a recent race. Negroids only appear in about the last 6-12,000 years or so in the context of agriculture. The genesis of the Negroid race is probably in the Sahel region, especially the highlands of Guinea. They then spread over the rest of Africa in a slow manner. The tall and thin Africans live in deserts (Somalis) or in grassy and hills plateaus (Kenya). The original Africans, the Pygmies, were indeed small and compact. The Bushmen are not very large either, and they are rather thin. Negroids have a number of heat adaptations. Excessive UV radiation during pregnancy destroys folic acid stores in the body of child, leading to birth defects. This is probably the main reason for melaninistic skin. The wide nose probably cools air it is breathed in, and it least it cols it more than a long narrow nose which probably heats it up. Black hair is perfectly adapted to heat. It absorbs heat well and allows sweat to run off. Straight hair might quickly become sweat soaked in extreme heat. Note that also Negritos, Melanesians and Papuans, all tropical adapted, have varieties of kinky hair probably retained from Africa. They probably moved out of Africa with kinky hair and saw no reason to get rid of it by moving to a tropical zone. If I am not mistaken, Blacks also sweat a lot more than Whites. Black people are very well adapted to heat in spite in the relatively large size.