PIE vs. Proto-World (Proto-Language)

[JoatSimeon at aol.com]

As far as African language families go, most of the area below the Sahara has
seen rather drastic shifts over the last few millenia.

The enormous expansion of Bantu languages from a small area of the Cameroons
to more than half the continent is the most obvious; more recently,
Fulani/Peul has spread from the Senegal region in pockets as far east as Lake
Chad, and the Nguni sub-group of Bantu reshuffled much of southern Africa.
Or on a smaller scale, Maa (Masaai) has spread down the Rift Valley, and
Galla/Oromo into the Ethiopian highlands, or Somali in all directions, since
the medieval period.

There's no reason to believe all this mobility started just as we came into
position to observe it, so extrapolating from the present linguistic
situation back beyond the last couple of thousand years is, to put it mildly,
very speculative.