Many factors line up for why Africa was the nursery of mankind but utterly unable to produce a competitive advanced civilization to keep the Europeans from carving the continent up like a Christmas goose. Those powers divided the continent up not according to tribe or affiliation but by vague maps using rivers as boundaries instead of focal points. Throw in the great powers keeping the continent divided in their world wide power struggle, the people divided both with-in tribes and social classes, it was messy. Then a cold war where neither super power cared about the character of the general they backed, just if he was a Marxist tyrant or capitalist one.
These days countries without resources we wish to exploit sit in benign neglect, those with resources we demand follow the same old pattern of we supporting the guy who grants our corporations sweet trade deals. I'd say while all humans can trace a line back to Africa, a lack of a strong linage in more modern times hinders it's development.