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July 04, 2004

The cheating lives of ladies

Newsweek has a showcase article titled "The Secret Lives of Wives" that chronicles the increasing in cheating among women. This is the sort of complex topic that needs to address hard-wired parameters, cultural constraints and individual motivations. It seems improbable to me that the two co-authors of this article read books like The Red Queen or The Blank Slate since their explanatory models tend to focus on the cultural and the individual, but it is I think a fragmentary picture to leave out the biological, as all three form a seamless whole that might explain social trends more realistically to readers, who after all often have an intuitive understanding of evolutionary factors.

The fact is, all cultures have equal, or more likely, harsher strictures against female infidelity than male "straying". The evolutionary reason seems obvious in the context of an EEA where there is scarcity of resources, men raising children who are not theirs genetically suffer a bigger hit than women who have to deal with less attention from their husbands, though he might still give most of his resources to one particular wife & their common children.

Interestingly, the article mentions women leaving for "wealthy" and "exciting" men, or fixating on personal trainers. This seems like a classic cads vs. dads issue. Certainly on a proximate level of the individual, one could hypothesize all sorts of "reasons" that a woman might make the decision that she does, but it is often instructive to take a step back and look at the overall pattern.

One thing that the article focuses on is the tendency for these affairs to happen in women as they age. As I've noted before, on the physiological level, there are various types of love, and the ardor of each might have different levels of waning and waxing intensity as a function of time. That is, a 45 year old woman that was married at 20 finding an affair "exciting" should be no surprise on the physiological level. On the evolutionary level, it is highly possible that pair-bonds on the order of 20+ years were not selected for, that is, mortality and the fact that the children had already reached maturity might have resulted in far less of a fitness cost if there was a dissolution of a relationship. The sexual dimoprhism (differences in morphology between males and females) in humans suggests that pure monogamy and fidelity is not the norm, rather, a mixed strategy, along with some expectation of infidelity might be the norm (human testicles are equidistant in size between those of chimps and gorillas, among the latter there is a lot of "sperm competition," while among gorillas the males tend to keep a close eye on their harems).

Of course, contexts change, some of the male "release mechanisms" toward female infidelity have been enshrined in cultural norms, in law and custom. Laws codified by a literate class and inserted in religious dogma can be difficult to modify later on. With the rise in life expectancy, and the affluence of American females (1/4 earn more than their husbands), innate release mechanisms within the cognitive substrate, and the cultural universals that they have spawned, have to face an environment far different than the EEA. The result is the confusion that you see on display in American culture today. The interplay between various forces might result in a new equilibrium.

To some extent in the EEA, and as the laws imply, "paternity was probability, not surety" [1]. The rage and violent reactions of males toward female infidelity was likely an adaptation to this reality. But today, with paternity tests, this is to some extent a superflous adaptation. The British push to roll-back secret paternity tests is wrong-headed. Surely it will cause a short-term disruption as re-equilibriation of social norms will not occur overnight [2]. But in the long term, full confidence of paternity might allow more acceptance of female infidelity in a fashion similar to the more open attitude that is found among male homosexuals. This sort of proposition won't make cultural conservatives happy, but the reality is that this sort of technology will automatically cause changes in human societies, and we need to figure out ways to deal with them, no matter if they cause us discomfort. There are, as noted in the piece above, more prosaic changes pushed upon us by the modern world, the fact that women encounter many more strange males in their lifetime in the workplace, and the proliferation of information technology that amplifies female social intelligence and reach.

Finally, I won't discount the impact of random-walk cultural changes and fads. On the simplest level, theorists have already shown that baby name popularity fluctuations can be modelled as genetic drift. Cultural fads, within the constraints and parameters above, require a level of flexibility in our conception of a normal society, as the mob tends to move in various directions. I'm wouldn't assert that all social changes must have a "reason" behind them. But something like female infidelity doesn't seem like a fad to me, rather, it seems to satisfy deep-seated psychological cravings, which can be explained by physiological changes in the life cycle of relationship shaped by evolutionary forces, as well as the relaxation of cultural and social constrains that emerged out of the interplay of more biologically hard-wired compulsions with the realities of the EEA, and especially post-EEA pre-industrial societies. If this is the "information age," we should take all the information come out of various disciplines to heart, and use it to analyse trends and patterns.

[1] American males who wish to naturalize children they had abroad with non-Americans who for some reason were separated from those children have to jump through more hoops that women. Why? The reason is the assumption that paternity is not as easy to establish, which of course is ridiculous.

[2] There is a common legal argument that one must act in "the best interests of the child." So, if a man agrees to be the father on a birth-certificate, he takes upon his shoulders life-long duties. There are many contexts where this happens, from casual flings that never crystallize into relationships all the way to men who have been unknowingly cuckolded and find out the true paternity after a divorce. I think it should change to "the best interests of children" rather than "the best interests of the child." The acknowledgment of new technological and social realities into the law will foster long term social satisfaction, as opposed to the short term familiar compromises made now.

Posted by razib at 08:39 PM