the article didn't point to any evidence that some human genetic lines stay at the top for generations due to social context vs. say inherent qualities. The article pointed only to correlation. Such correlation doesn't means causation, especially considering that the social context may be a direct result of inherent qualities (while inherent qualities may be only very indirect result of social context). This is why comparison with baseline where we _think_ inherent qualities play significant role is important.

If, for example, aristocracy like English lords started (or was significantly affected through such a process) as most successful fighters, and didn't have significant gene mix with "lower" classes, when it would be very reasonably to suppose that their inherent qualities is somewhat different.