This article is about migration of Bantu-speaking people 5000 years ago, not innovation in general, and isn't really applicable to scientific/technological discoveries. Perhaps link to the original paper without the clickbaity title:
Wow, good catch—that's worse than average even for a press release farm.
We've changed the title (from "Human innovation more trial-and-error than 'lightbulb' moments"), but have left the URL because the popular article, distorting as it is, provides more background. Also, the researchers themselves are pushing this interpretation, to judge by the quotes in the article, so it isn't just spin by a headline writer. Anyone who wants to read the paper can follow the link you've helpfully provided.
"Bantu expansion shows that habitat alters the route and pace of human dispersals" http://www.pnas.org/content/early/2015/09/09/1503793112