i actually don't think it's unlikely that early africans may have made it to south america via boat. we know that they travelled along india by boat at a very early date, and we seem to have evidence of cocaine in very old egyptian tombs, indicating that it was a possible journey.
but, i realize that the world is not flat and that it makes more sense to send them across the atlantic. that said, the documentary offers nothing in the way of such an argument.
but, near the final few minutes i all of a sudden understood: perhaps the fuegians may carry on in our genome - just like the "american aborigines" carried on in theirs.
it's subtle race-washing. in the wild.