Marginal Revolution discusses the economics of polygamy, though in fact they're really talking about polygny (one male, multiple female). The discussion was triggered by a NYT story on the abandoned teenage males surrounding a pseudo-Mormon cult.
Humans have often practiced polygyny (with rare polyandry), but polygyny is rare in technological societies. I'm sure sociologists have theories about why this might be so, but it's interesting to speculate about how the leftover male problem changes over time.
Leftover males have to be eliminated -- or they'll cause problems. The least disruptive way to eliminate them is probably through continuous warfare. At some point in the development of human cultures I wonder if war started to get more costly, at the same time that the value of the males increased, such that it became too expensive to have leftover males ...
PS. Many people worry about China's current leftover male problem. Polyandry in China would help restore the critical balance ...
Update: I fixed my typo in the title. (was assymetric)
