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a second reason for supposing/proposing life (human life) first evolved in africa is modern day genitic evidence.
--based on two different sets of 'markers' --the Y chromosome, and mitocondrial dna--the modern day evidence makes it clear, africans, (and this is based on many group of people, the 'bush men', pigmies, zulu's, (and many other groups, including the burbers of the mediterranian coast) there exist more genetic diversity in Africa, than on any other continent. and based on genetic markers, the oldest human population are the people now called "bush men"--
given this modern information, (and the fossil evidence--)which is incomplete, (so much of the earth gets recycled every year, with habitates going under the water, (sea levels (or relative sea levels) have changed for reasons besides the ice ages. --it seems likely (how likely? i've read everything from very to extremely likely) humans (as we now know and love them) evolved from prehuman animals living in various parts of africa.
