Did selfishness — or sharing — drive human evolution? Evolutionary theorists have traditionally focused on competition and the ruthlessness of natural selection, but often they have failed to consider a critical fact: that humans could not have survived in nature without the charity and social reciprocity of a group.

Last week on Slate, evolutionary anthropologist Eric Michael Johnson explored the question against the backdrop of two cultural events in 1957 — the consequences of the rogue, selfish activities of a pygmy hunter in a Congo forest, who used the group’s collective hunting efforts to benefit only himself, and in New York City, the publication of Ayn Rand’s novel Atlas Shrugged, whose protagonist champions the author’s notion that human nature is fundamentally selfish and that each man “exists for his own sake, and the achievement of his own happiness is his highest moral purpose.”

Atlas Shrugged counts many politicians as admirers, perhaps most notably Republican vice presidential candidate, Paul Ryan, who cites the book as one of his main inspirations for entering politics and is known to give Rand’s books frequently to his interns.

Read more at Times.