It’s a very difficult question to answer. For a start, there isn’t just one type of humans, but rather many. There are roughly five human types (the five races), with the remaining being more like subspecies or ethnicities.
However an alternate theory is that there are really only two distinct species: modern humans and Neanderthals (or Homo neanderthalensis). This alternate theory holds that if you take into account genetic diversity within each so-called “race” you find the same level of diversity throughout different regions of Africa as between any two African populations, despite how much time has passed since their ancestors left Africa for Eurasia.