Thursday, November 5, 2009

How many babies are born to involuntary foster fathers?

Is there really a conspiracy against fathers to have them dwell in false (paternity) certainty?

EvoPsych studies leave little doubt about it. At least on a smaller scale. In each case of paternity theft, there are several people who would profit from a man's ignorance. It's him against many: The cheating woman will be able to keep his commitment and resources. Her relatives are interested in keeping that arrangement, too. And last not least the baby itself.

None too surprisingly, then, both mothers and their relatives have been empirically shown to manipulate a man's belief in paternity by commenting on the baby's resemblance with the "father". It is important to note that this is a flat out lie, since other studies demonstrate that people in general have a hard time matching infants with their fathers based on physical resemblance alone.

The reason for the latter is that newborns have evolved a clever mechanism of "concealed paternity" (ever wondered why they all get born with blue eyes?). The mere existence of this phenomenon is testament to the high rate of cuckoldry in human ancestry: babies who looked too much like the alpha male who actually fathered them got weeded out thanks to infanticide (read: the rage of beta male providers who got a rare glimpse of reality).

But, what is the actual number of children that get born to (presumably ignorant) non-biological Dads?

One of the most commonly encountered numbers, that seems to believed by the majority of the population, is 10% (!). However, the most credible sources typically add a huge confidence interval and thereby end up with meaningless estimates, such as 1-30%.

More recently, a meta-analysis of international studies claimed to have resolved the issue, by adding another factor - paternity certainty. The authors concluded that "for men with high paternity confidence rates of nonpaternity are(excluding studies of unknown methodology) typically 1.9%."
Even though this number is twice as large as the lower (1%) limit provided in common estimates, it could explain why studies disagree since the number these researchers found for low confidence fathers resembled the upper limit of 30%.

We don't know the fraction of high vs. low paternity certainties (it is likely to correlate with socioeconomic status; studies find that the rate of non-paternity is inversely related to house hold income), but its conceivable that averaging across such a bimodal distribution would result in the commonly quoted 10% indeed.

What's suspicious about the study is that the abstract does neither mention the mind-blowingly high rate of  non-paternities for "uncertain Dads" nor the fact that for this reason a population average will be substantially higher than the 2% rate found in the "confident" sample, but instead states that their finding is "substantially less than the typical rates of 10% or higher cited by many researchers."

This does not sound like the authors were ambivalent and hence objective about the outcome (no wonder: studies who claim evidence against conventional wisdom in science make researchers famous). 

Neither do others, who picked up the study and selectively quote more data that seems to support it (no wonder: there is a societal bias towards downplaying cuckoldry and paternity fraud).

So, can we take away from this that a man is "in the clear" if he feels like he can trust his wife (pretending that your chances of getting bitterly betrayed in 2 out of 100 cases is not a threat)?

Let's crunch some numbers here. A lot of data on this issue is freely available on the internet. But first, let's look at the caveats:

- DNA testing is the only way to know for sure, but DNA testing is always biased.
The reason for that is that scientist cannot just ask random people to join a study on non-paternity.
The samples usually obtained are either from "low confidence" samples, i.e. sent in by men who have significant doubt on their paternity. These samples are often forced upon women in the course of law suits etc.
Other samples are from "high confidence" groups, who happily engage in the study since they "feel safe". It is important to note that this relates more to how the women feel (!) than the men's sense of security. It is common sensical that women who will feel that the DNA test will cause trouble are likely to refuse participation.
It follows that the "bimodal distribution" in the above study is likely to result from this sample bias towards the extremes rather than a true representation of the general population.

Some DNA-based paternity studies tackled this problem by obtaining random samples, and using indirect methods to estimate an underlying pattern of non-paternity:
Randomly obtained DNA from people with the same surname (Sykes) in England found that "almost half the sample shared the same Y-chromosome haplotype, which has not been observed in control samples either from the same geographic region or from the United Kingdom as a whole. This points to a single surname founder for extant Sykes males". Behold the power of alpha! The authors, however see this as evidence of a surprisingly low rate of non-paternity (1.3% per generation). The question remains whether this holds true for the descendants of lesser men too.
DNA-screening for hereditary diseases revealed an informally communicated non-paternity rate of 1.4% in the British population (a study using similar data from Switzerland comes to an estimate of 0.8%). This sample is more prone to bias since the women were explicitly made aware of fact that the test could reveal cuckoldry and even asked not to join in case they feared such an outcome. The British doctors claim that only 1% of women chose that exit route. And another 1% refused to join for other reason. Note that this was not a random sample across the population, but people who sought medical help for their children.
Another genetic study using a large data set of blood samples collected for a different purpose in Hawaii came up with an equally low estimate of 2.3%. Again, the sample was not fully randomized, but required the consent of participating families.

- Other methods of estimating paternity rates are less direct but are void of any bias.
Scientist had some great ideas how to "indirectly" test for paternity fraud. Some of these include:
ratings of emotional closeness - estimate of non-paternity: 12,6%
actual investments of kin - resulting estimate of non-paternity: 13-20%
investments of grandparents - resulting estimate: 9-17%
blood typing - of a Mexican sample - resulting estimate: 11,8% 
blood typing a native tribe (the Yanomamo) - resulting estimate: 9%
routine blood typing at birth (unpublished) - despite the unreliable nature of this approach, this remarkable data set is the closest to mandatory paternity testing; the resulting estimate: 10%


What's remarkable about these studies is that they all point to a number close to or higher than 10%, which a much narrower confidence interval. It is unclear whether this reflects the unbiased sample, or the fact that fathers and kind would benefit from an overestimation of non-paternity.

Now, many of these estimates are based on human instinct, which in return is based on what happened throughout evolutionary history. It is conceivable that the lower results in (unbiased) DNA test are due to. During the past decades things are likely to have changed drastically when it comes to infidelity. The advent of chemical contraceptives is likely to have raised the rate of cuckoldry while lowering the rate of non-paternity.

Reliable data on adultery is even harder to find. According to a wide survey in Great Britain, 10.1% of "committed" women had sex with at least one more partner in the past 12 months. This matches other self reports that made it into the scientific literature (6.9-13.8%). However, note that the actual rate is likely to be much higher. Other studies have shown that when it comes to sex partners, women tend to cut their numbers in half.

Given their gossipy nature, all these findings are fine material for cocktail party conversations. From personal experience I can say that the most frequent reaction by women still is denial. It is likely that this will change soon as it becomes harder and harder to look the other way. My prediction is that women will then switch their strategy from "not true" to "not a big deal" in order to save the status quo. And his trend has already started.

7 comments:

  1. "Not a big deal" is not going to work. Widespread deception of men, in which they themselves often collude, has kept things on an even keel. But women cannot simply front out infidelity on the basis of their current power advantage in the sexual market because the human male has a inbuilt guarantor against this over which he has little control: rage.

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  2. Knowledge will set men free . . of they tyranny of women.

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  3. this reminds me of every single Maury Povich show where the slag girl tests like 5 different dudes, and for each one, she harps about "that baby got yo' nose! take care a yo' responsibilities.".....then you hear that epic phrase of freedom, "You are not the father."
    Cue celebratory dance by the guy and tears from the slag. mmm. it makes my heart sing. here's a link to a collection of them - hilarity. i just had this added to a post of mine. mmmm. my heart singeth loudly. http://www.youtube.com/watch?v=ccTsTe8yaYQ

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  4. Marquis... I -love- those videos.

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  5. Not a big deal is the approach we're going to see much more of -- not just about adultery, but specifically about non-paternity. The argument is that the "right" of the man to know the truth of the paternity of his wife's children is outweighed by the interests of the woman, the child and the state/society in having that child (and the other kids, if any) continue to be raised in that stable home environment with the man's investment and support. This is even more the case if the non-paternity is discovered after the man has already been duped and has been acting like the father -- the one area of the law where someone who has been defrauded is held to the standard of their behavior as a result of the fraud in such a way as to perpetuate the fraud and perpetuate continuing obligations based on the fraud.

    I don't see the laws changing much in our favor on these issues -- as far as most people are concerned, men in these situations should "man up" and so on. The only way we get around this is by mandating DNA tests at birth (avoids the "de facto father" argument) -- but it's highly unlikely that women, with their political clout, will ever allow that to happen. On the surface they'll say that it's insulting and demeaning and so on (which it is nothing of the sort -- it is a test done in the background with no involvement from the mother like the other round of routine tests done shortly after birth), but viscerally we know, as men, that it is their instinct to protect their ability to cuckold, and mandatory DNA testing is the biggest threat ever invented to a key mating strategy that women have had since forever --> either if you can't snag the alpha as a pair bond, snag the beta as a pair bond and have the alpha sire your kids (or at least one of them). Mandatory DNA testing shuts that down completely, and so women will resist it in a visceral way, regardless of whatever rationalizations they mouth about it.

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  6. @Novaseeker - add the resistance against mandatory DNA testing to my list of evidence for the frequency of paternity fraud and society's combined attempt at making it a non-issue.

    Any men who ever got a job in a Western nation had to go through background checks (for credit score, felonies, sometimes even health issues). It's a similar situation - mass distrust/testing given a few cases of fraud. But somehow nobody cries out that this is "insulting and demeaning".

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  7. Hey, 11minutes, you mentioned you were German. Same here. I was wondering wehn you have the time if you could translate this song, my German is not good enough yet for me to be able to do so. http://www.youtube.com/watch?v=fR7YmBWis-w

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