>>508517068>>508518462>>508519112Somewhat, it stores extra blood because blood is the body's main heat distribution system. Africa is fucking hot and big lips mean more surface area for heat to escape from.
In fact, pretty much every weird anatomical trait Africans have can be traced back to heat.
Puffy hair: High surface area vs volume ratio holds water and improves airflow, like a heat sink
Dark skin: Absorbs sunlight that would damage anything beneath the skin
70 IQ: They don't have to deal with the harsh winters that northern races do, so anything above this is a waste of calories that could be put towards running. What is Usain Bolt's IQ? The answer is that nobody gives a fuck.