This might end up as a "nature vs. nurture" question. The flip side of this argument, is that in modern monogamous societies (especially with birth control ena

This might end up as a "nature vs. nurture" question. The flip side of this argument, is that in modern monogamous societies (especially with birth control enabling easy family planning), the smart and industrious couple will probably have the ability to devote more time and resources to the relatively small amount of children they have. Whereas, the smart and industrious polygamous male (traditional polygamy tends to almost always be patriarchal)'s resources will be spread more thinly among their X wives and Y babies. At present, I'm not aware of a current polygamous society that is known for technological or intellectual sophistication. In addition to the above, the overall social structure in polygamous society seems to be negatively impacted, owing to the large quantity of unmarried, potentially violent, men that need to be dealt with somehow (as alluded to in The Economist article). Consequently, I'm also not aware of a polygamous society which embraces liberal values politically, or embraces democratic style political structures. In other words, from the evidence I see, it seems likely to me that the negative consequences of polygamy wipes out any potential genetic benefit.