Because every liberal in the US (and probably the world) is flat-out convinced that Africa is the source of homo sapiens, or homo homo sapiens, or something or the other.
The oldest remains apparently have been unearthed there. I wonder, though, if Africa may not have been the first place man appeared, but the last. The ancient remains, then, would be available simply because they are the newest, relatively speaking.
:)
Homo Sapiens Sapiens is the sentient modern human.
Homo Homo Sapiens must be a liberal.