Friday, May 29, 2015

About as bad as behavior genetics reporting gets

A story in the New York Times a couple of days ago, linked here.  The story was prompted by a paper in Evolutiona and Human Behavior by Brendan Zietsch et al, linked here. The title says it all:  "Infidelity Lurks in Your Genes."  I should say at the outset that the article itself is fine.  I'm not sure I buy the argument that the heritabilities they estimate are higher than others in meaningful ways, and there are obvious reasons to be skeptical about the small sample candidtate gene results, but in the paper the authors are perfectly up front and thoughtful about the limitations of their conclusions.
and in fact, the OXTR and sexuality work has most of what you could want out of this kind of study, especially meaningful animal models.  This post is not about the science.

But the Times article gets just about everything wrong.  Of course, there is the ridiculous overstatement of the psychological meaning of heritability.  OK, infidelity is heritable, but so is everything else, so if infidelity lurks in our genes so does everything, which I suppose is true.  What they mean is, likelihood of infidelity not independent of genetic endowment.  The important lesson of complex behavior genetics is about the human condition-- we all create our selves and regulate our behavior in the constant presence of genetic endowment-- and not about anything particular about individual behaviors.  There is no other aspect of sexual behavior to contrast with infidelity that does not lurk in our genes and is therefore under our perfect pscychological control.  The world doesn't work that way.

Then there is the confounding of the twin evidence and the candidate gene work.  See the paragraph that begins "He found that 9.8%..." It starts out talking about candidate genes, and then switches to saying that 40% of the variance can be attributed to genes.  The average NYT reader would have absolutely no idea that it isn't OXTR and vasospressin that acount for 40% (in fact they account for a couple of percent, and that is almost certainly an over-estimate)

Then there is the  evolutionnary  part, which is like a parody..  Men cheat because there is an evolutionary advantage to reproducing with many women.  But women cheat too.  (I like the old jingle:  Hoggamus higgamus, men are polygamous.  Higgamus hoggamus, so are women.)  Why do women cheat?  Well, because they enjoy it!  But don’t worry, that has a biological explanation too, they enjoy it because dopamine.  Once again, I know there are many interesting evolutionary things to say about fidelity and infidelity, and reward systems or whatever.  But it should be a science reporters job not to reduce them to nonsense.  It does the field no good.

The article closes with a story of an acquaintance of the reporter who has cheated on her partner repeatedly and compulsively over the years.  (By the way, this seems like a lot of information to reveal.  A bisexual woman, apparently married to a man, who is an acquaintance of the writer.  The guy is a psychiatrist.  He should be careful.) Recently the relationship has been bad, so the writer can write it off to psychological causes.  But she also cheated early on in the relationship, which the writer takes as evidence that her cheating is “innate”.

People, like I say, are partially self-determining organisms who are born into the world with evolved impulses, some of them universal and some of them differing among individuals.  Managing the relation between the evolved impulses that we share with voles and our complex self-regulating psychology (which also evolved, of course, but only exists in primitive forms in voles) is the essential human activity; understanding it is the ultimate goal of psychology.  Nature didn’t do us the favor of giving us some desires that are innate and others that are strictly psychological, although it is always tempting to think that way because the alternative is so daunting.  From the point of view of humans-as-biological-entities these questions are the basis of evolutionary psychology and behavior genetics; from the subjective point of view of living people they are (forgive me) psychoanalytic.

I have gathered recently that there is a movement in meteorology to change the way weather forecasting is discussed in the popular press.  The excellent Capital Weather Gang in the Washington Post no longer scream headlines like, “Blizzard to Bury DC!”.  Instead they talk in terms of probabilities and confidence intervals, discuss how their forecasts might go wrong, weight the different possible outcomes, consider the limitations of existing weather models.  (Those of you in the mid-Atlantic might also want to check out the WxRisk feed on Facebook.) It’s less than thrilling than Blizzard! But ultimately more interesting, and leaves readers with a sense of what meteorologists actually do.  We need a similar kind of popular press reform in BG.


1 comment:

Michael Vanyukov said...

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