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September 08, 2004

The handicap & the helping hand

Back in 1996 when the "Microbial Mars Rock" came to light I asked my physics professor at the time (whose wife was a former JPL scientist) what he thought of the findings. He told me that all his friends in the space science community found it very plausible, and I swear I saw a twinkle in his eye. Later I read that scientists at conferences would assail skeptics with hostile questions whenever this topic came up. The implication was clear: many space scientists had a bias in that they wanted there to be evidence of life on Mars, that is, Life-on-Mars was their pet hypothesis. I don't know if this was true, I didn't see any broad-based survey which indicated that space scientists had ceded professional skepticism in this particular area of extraordinary claims, but it illustrates a general principle: some ideas and models are more congenial to a given audience than others.

For example, while The Big Bang Theory is accepted as rather robust model today, for decades there was scientific resistance because it seemed to open the door to cosmological proofs for the existence of God (recall that Einstein inserted the original Cosmological Constant because of an implied expansion of the universe). It did not help that one of the proponents of an expanding universe was a Catholic priest! In any case, after the discovery of the Cosmic Background Radiation only a few diehards adhered to the Steady State Hypothesis, science had had its day, no matter the implication for theology.

But just as the scientific community was skeptical of The Big Bang Theory because of its theological implications, the general public seemed to be mildly enthusiastic. In the United States glossy magazines often like to highlight the model as the centerpiece for their yearly God & Science issue (with the usual subheading that implies that the arrow of science points squarely to the God Hypothesis).

Reigning orthodoxies are the mountains which new ideas must climb over. This is clearly an issue when someone from this blog brings up the idea of inter-group differences, that is, Human Biodiversity, the assumed truth tends to run along the line that 'race does not exist,' and only uneducated toothless rubes would contradict it. This means that those of us who are open to this avenue of inquiry must be above reproach, and we expect a rather steady stream of abuse and invective from the other side, because they command the heights.

In contrast, the situation with evolutionary psychology, depending on the context, is the reverse. The public yearns for biological explanations of human universals, and though dissenters might have won the battle in the academy, the war of public opinion has turned against them. So when speaking of EP (evolutionary psychology) the 'other side' tends to be, in my opinion, more defensive. This can sometimes result in intellectual laziness on the part of those who advocate evolution, biology broadly speaking, as a filter through which human action must be sifted.

Apropos of this very point, a few weeks ago I read the book Mother Nature, and the author repeated the fact that women (and her relations) tend to reassure the putative father that the baby looks like him. The implication is that they are making sure that the father does not doubt paternity. What I found interesting though was the author's reference of a paper which suggests that babies tend to resemble their fathers more than mothers. That is, there is more incentive to resemble fathers in terms of "baby fitness" (a father's paternity is "theory") than a mother (a mother's maternity is certain). All is good, and I thought the two points, the ultimate & the proximate, dovetailed rather well.

Then I did some googling...and I found this paper which not only did not reproduce the result above, but offers a powerful theoretical objection: if a child resembles the biological father, the risk is increased if it is placed in the presence of a male who has been cuckholded, that is, if the putative father is not the biological father, then it is likely that he will be able to more easily detect the mother's deception. The lesson is that when it comes to human evolution and behavior, we are all narcissists, literally self-interested, and we have to prod ourselves to keep digging and reexamine our assumptions [1]. And further digging found this paper which concluded that males are more likely to want to "adopt" a baby face morphed from their own features than women (implication: men like babies that look like themselves). Reality, nature, exists, and the data is out there, we simply have to parse it, tease it apart and reconstitute it in a way that allows it to express its native structure. This requires patience and subduing our natural enthusiasm. It also means that we should not veer to the opposite extreme and declare the task foolish and not worth attempting.

Related: Looking up information on paternity, I stumbled on to this research, and will copy the key findings (if you follow the link, rescale to 300% for better viewing of the PDF):


  • Men who are certain of paternity are correct 96-98% of the time.
  • Men who have doubts about paternity are not the fathers 30% of the time, but they are still the father 70% of the time.
  • The author finds little difference in worldwide variation when men with high paternity certainty are partitioned from those who have paternity doubts. The paper (not published) doesn't give all the data, but I suspect that there would be variance in the frequencey of men who belong to each category by region (for example, I am skeptical that traditional Saudi men would have as high a concern about paternity as Cuban men-and even if they are cuckholded, it would likely be by a close relative since traditionalist Saudi women would likely not be exposed to any non-relatives).

The above data suggests that:

  • Social contexts where theoretical paternity exists for the male are rather good at translating it into real paternity (significantly deviated from the ~9% misattributed paternity median worldwide)
  • Men tend to err on the side of suspicion. Their doubts do not reflect reality the majority of the time.


Addendum: David B's two previous posts on cuckholdry, here & here. My previous, though unsubstantial, post on paternity. I do stand by my assertion that cheap & easy confirmation of paternity will contribute to general amity.

[1] I have sometimes wondered about the situation of a black man who migrates and is accepted into a white tribe. If he marries into this tribe, infidelity is obviously something that is a risky proposition for him. On the other hand, his partner is also taking a large risk if she engages in infidelity. In the case where an individual is a "rare phenotype," incorrect recognition, that is, a false positive or a rejection of a valid hypothesis (in the context of paternity) would be unlikely since one's own offspring would be variant. In the context of humans, with our tit-for-tat morality and common, though not universal, infidelity taboos, the "dad" strategy would be best for an individual who is a newcomer to a given culture/tribe and exhibits a different phenotype. The negative consequences of the wives of social peers birthing children than are clearly those of an alien male are clear, while the ability to keep track of one's own reproductive success with nearly perfect accuarcy is a boon.

Posted by razib at 12:09 AM