Hidden Games

There is no single human nature.   This is obvious enough – people vary strongly in their psychology and behavior. The differences show up early in life and don’t seem to be affected much by parental rearing style.   It would be nice to understand more about the ultimate causes of variation in human personality,  partly because of practical implications, mostly because we find ourselves very interesting.
To some extent, the ultimate source must be forces other than natural selection:  mutational pressure, infectious disease, and new environmental insults.  Mutations happen, viruses get into the brain, you may even have a steel rod fired through your skull, like Phineas Gage.  Such things can affect your personality.  In general, one would expect that these are the causes behind obviously maladaptive behavioral syndromes, like homosexuality and schizophrenia.
 Most human behavior is universal and adaptive, or used to be in past environments .  We eat when we’re hungry, fear spiders and snakes, love our children – these essentially universal behaviors are the products of natural selection.   Behavioral patterns of this sort exist because they have worked over the long haul, worked in the sense that their bearers left descendants.   Such patterns can be thought of as strategies  –  patterns or rules of conduct that, on average, led to reproductive success in the human past.
But to what extent is variation in human behavior adaptive? Why shouldn’t there be a single best strategy?  Often there  is, but not always.  It depends on whether the payoff of a particular course of action is frequency-dependent – in other words, depends on what other individuals do.  Running from a  forest fire pays off whether anyone else runs or not, but the payoff of running for tribal chief decreases as the number of candidates increases. If everyone is passive (a ‘dove’), aggressive individuals (‘hawks’) prospers, but as hawks becomes more common, they increasingly run into and fight other hawks, so their payoff decreases.  If the cost of fighting among hawks are high enough,  the equilibrium solution is a mixed state consisting of both hawks and doves.  Thus there is no single best solution, no single optimal behavior – this is often the case with social interactions.
The next question is whether adaptive variation in behavior/personality  is fixed or flexible, heritable or not.   In other species,  we see both. Sometimes an individual can pick one or another life strategy based on exterior clues.  If a female bee larvae is fed royal jelly, she becomes a  queen, otherwise she becomes a sterile worker.  The capability to assume those different roles is adaptive and presumably a result of natural selection, but it is not noticeably heritable, because all females bees have it.  In other cases, like those pesky fire ants that  exhibit single-queen and  Los Angeles-style multi-queen colonies, the two morphs are determined by the two alleles of a single gene, and the behavior difference is heritable as all get out –  and also shaped by natural selection.
 Since we are arguably a lot smarter than ants or bees, you might think that most adaptive personality variation in humans would be learned (a response to exterior cues) rather than heritable.  Maybe some is, but much variation looks heritable. People don’t seem to learn to be aggressive or meek – they just are, and in those tendencies resemble their biological parents.   I wish I (or anyone else) understood better why this is so, but there are some notions floating around that may explain it.  One is that jacks of all trades are masters of none: if you play the same role all the time, you’ll be better at it than someone  who keep switching personalities.  It could be the case that such switching is physiologically difficult and/or expensive.  And in at least some cases, being predictable has social value.  Someone who is known to be implacably aggressive will win at ‘chicken’. Being known as the sort of guy who would rush  into a burning building to save ugly  strangers may  pay off, even though actually running into that blaze does not.
Also, if a particular role or personality type only became viable recently – say,  20,000 years ago –  a mutation that induces that personality will spread.  Initially it will not be part of some super-flexible system; the required modifier genes, that would  turn those tendencies on when they pay and off when they don’t,  would take  a long time to evolve.
hn Tooby and Leda Cosmides, leading evolutionary psychology mavens, have argued strongly against the possibility of heritable, adaptive behavioral  variation in humans.  In fact  their arguments imply  that no such thing should exist in any  species, and  since we’ve found genetic morphs in lizards, birds, crustaceans, ants,  and butterflies, it’s safe to say that John and Leda  are wrong on this. But at least one of their arguments is interesting: they argue that adaptations, including behavioral adaptations,  are usually generated by complex,  co-adapted sets of genes (true), and that such gene complexes would be broken up by sexual reproduction (also true):  even if Dad had a set of alleles that made him a natural blacksmith or tap dancer,  his kids would never  inherit that whole set and the talent should disappear.  I think they’re on to something with this argument, because it seems that in a significant numbers of cases, these genetic morphs are determined by a single gene: different alleles of that gene specify different morphs. Maybe the heritable variant is in some way a simple trait: I can imagine a number of ways in which that could work. For example, what if simply losing a particular complex adaptation is adaptive when rare?  I can easily believe that a complex behavioral adaptation could be stopped cold by a  single mutation.  Or, for that matter, what if greatly intensifying a particular behavior or drive – turning up the volume knob –  was adaptive when rare? Can I imagine a simple mutation that turns up the volume in some way? Surely.  And, of course, such simple initial changes can be gradually refined by natural selection.
People underestimate the information that can be packed into a  single protein. A protein 200 amino acids long could express (21)**200 difference sequences: that’s a lot of possible messages.  21 instead of 20, because of seleno-cysteine.  I’m not even counting the impact of sequence variation in the promoter region.
There is another way in which a whole different life-strategy can be packed into a single variant allele: the gene can act as a switch. The sex-determining gene SRY is the best example of this.  There are many genes  that are fully expressed only in one sex while existing (of course) in both. Modifier genes sense the state of the switch and turn other genes on and off accordingly.  Every guy has the necessary genes for a uterus, but they just sit there, waiting for a chance to show their stuff in a female descendant.  The same thing could happen with morphs: probably does happen.  It would be interesting to check for genes that are highly expressed in the single-queen fire ant morph but not in the multi-queen morph.  There has been plenty of time for this to happen,  since the polymorphism is millions of years old and predates the species.
This kind of game-theoretic genetic variation, driving  distinct behavioral strategies, can have some really odd properties.  For one thing, there can be more than one possible stable mix of behavioral types even in identical ecological situations.  It’s a bit like dropping a marble onto a hilly landscape with many unconnected valleys – it will roll to the bottom of some valley, but initial conditions determine which valley. Small perturbations will not knock the marble out of the valley it lands in.   In the same way, two human populations could fall into different states, different stable mixes of behavioral traits, for no reason at all other than chance  and then stay there indefinitely.  Populations are even more likely to fall into qualitatively different stable states when the ecological situations are significantly different.
In some cases, the states are not even time-stable.  There could be periodic oscillations.  Consider those crazy cichlids. There is a kind of cichlid in Lake Tanganyika that lives by eating the scales of larger fish.  It attacks by swimming up from behind and snatching a scale or two from the side of its prey. Its mouth is twisted to the side, which aids in this specialized form of attack.  Some individuals have mouths twisted to the right ( right-handed fish) and others are left-handed.  Right-handers attack their prey from the left and left-handers from the right. Prey do their best to avoid these attacks, but they cannot be vigilant simultaneously against attacks from the left and from the right.  The handedness of the scale-eating cichlids is heritable and can evolve, as ids the tendency of other fish to be  protect their left or their right sides.   When most fish are defending against right-handed scale-eaters, southpaws have an advantage, and vice versa.  It appears that these two forms cycle over time, never reaching an equilibrium.
Barry Sinervo’s lizards have three male morphs: aggressive orange males that dominate blue males but that cannot compete with yellow males that imitate females – yellow males that  are successfully kept out by territorial blue males.  Scissors, paper, rock – but there is more since the same alleles in females results in r-females that lay many small eggs and k-females that lay a few large eggs.   Not too far away, the same species has only one male morph, the blues: either by chance or because of a different ecological situation,  the species has fallen into an entirely different societal pattern.
 What this means,  think, is that it is entirely possible that human societies fall into  fundamentally different patterns because of  genetic influences on behavior that are best understood via evolutionary game theory.  Sometimes one population might have a psychological type that doesn’t exist at all in  another society,  or the distribution could be substantially different.  Sometimes these different social patterns  will be predictable results of different ecological situations, sometimes the purest kind of chance. Sometimes the  internal dynamics of these genetic systems will produce oscillatory (or chaotic!) changes in gene frequencies over time, which means changes in behavior and personality over time.   In some cases, these internal genetic dynamics may be the  fundamental reason for the rise and fall of empires.    Societies in one stable distribution, in a particular psychological/behavioral/life history ESS, may simply be unable to replicate some of the institutions found in peoples in a different ESS.
Evolutionary forces themselves vary  according to what ESS you’re in.  Which ESS you’re in may be the most fundamental ethnic fact, and explain the most profound ethnic behavioral differences
 Look, everyone  is always looking  for the secret principles that underlie human society and history, some algebra that takes mounds of historical and archaeological  data  – the stuff that happens – and explains it in some compact way, lets us understand it,  just as continental drift  made a comprehensible story out of geology. On second thought, ‘everyone’ mean that smallish fraction of researchers that are slaves of curiosity…
This approach isn’t going to explain everything –  nothing will.  But it might explain a lot, which would make it a hell of a lot more valuable than modern sociology or cultural anthropology.  I would hope that an analysis of this sort might help explain  fundamental long-term flavor difference between different human societies, differences in life-history strategies especially (dads versus cads, etc).  If we get particularly lucky, maybe we’ll have some notions of why the Mayans got bored with  civilization,  why  Chinese kids are passive at birth while European and African kids are feisty.  We’ll see.
Of course we could be wrong.  It’s going to have be tested and checked:  it’s not magic. It is based on  the realization that the sort of morphs and game-theoretic balances we see in some nonhuman species are if anything more likely  to occur in humans, because our societies are so complex, because the effectiveness of a course of action so often depends on the psychologies of other individuals – that and the obvious fact that people are not the same everywhere.

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16 Responses to Hidden Games

  1. Ron Pavellas says:

    “One is that jacks of all trades are masters of none: if you play the same role all the time, you’ll be better at it than someone who keep switching personalities.” How does one “switch personalities”? What is a personality? If you use the Myers-Briggs Type Indicator (MBTI) the theory is that one’s personality does not change. Perhaps you are not talking about the individual? I think it remarkable that the ratios of the 16 “Types” to the sum of all types is regular, at least in the short term and in the USA: http://www.capt.org/mbti-assessment/estimated-frequencies.htm. I speculate that any given population in any given environment needs a certain ratio of types for stability or survival.

  2. FredR says:

    “Since we are arguably a lot smarter than ants or bees, you might think that most adaptive personality variation in humans would be learned (a response to exterior cues) rather than heritable.”

    What do you think of James Chisholm’s Life-History theory found in “Death, Hope, and Sex”? He argued that we’re programmed to optimize our life-history strategy (long-term or short-term) based on the kind of attention we receive as infants, which proxies for how dangerous our environment is. Different life-history strategies (which are fixed once programmed in) lead to different personality profiles (more or less tolerant of risk, more or less trusting of others, etc.). Is there anything to it or is it all just a bad explanation for what is actually the fixed genetic inheritance he might be ignoring?

    • dave chamberlin says:

      I have had my own life experience that struck home how important the love we recieve as infants is to how we treat others late in life. I grew up a spoiled suburban kid loved by his parents. After college I ventured out into the real world and was a social worker with inner city kids whom had the opposite treatment by their parents than I had. They had bounced through foster homes and orphanages their whole lifes. I was shocked by how cold, sociopathic, and prone to violence many of these teenagers were. There was a striking difference between the teenagers whom had been loved in their formulative years and those that had not been. Even in these foster homes you could immediately identify those kids whom been truly loved and those that had been not.

      Changing perspectives from my personal observation to history I would like to refer to Barbara Tuckman’s book “A Distant Mirror.” She writes “Of all the characteristics in which the medieval age differs from the modern none is so striking as the comparitive absence of interest in children.” It may seem terribly cold to not love your children as is so prevailent today but it was simply a coping mechanism nessecary when half your children died before age ten. Pre advent of modern medicine family life was as Tuckman says a cycle, “a child died and another one took it’s place.” If a child made it to the age of ten then time and energy were invested in them because then it was likely they would live into adulthood. I think here lies much of the answer as to why violence has decreased so much in modern times, why scandinavians for example have transformed from much feared beserker barbarians to some of the most peaceful people on earth. This is not to detract from the genetic piece for certainoly it is important as well.

      • harpend says:

        I don’t think that you can separate genetic from environmental effects with your observations. Kids, for example, are in my experience like cats: some want to be petted (“loved”) and some hate it. In order to support your hypothesis you would need some kind of experiment with controls. What we have, so far, does not support much if any effect of rearing environment. Even so I hope decent people will continue to love their children

      • FredR says:

        Professor Harpending:

        If I remember correctly, Chisholm cited your 1982 paper on father absence a few times (as well as related papers by your co-author Patricia Draper) in support of his argument. Did he misinterpret the paper? Have you changed your views? Or is none of this relevant?

        • harpend says:

          Yes, Jim Chisholm is on the same wavelength as we are. Jim thinks that there is stress involved in the effects of father absence, while we suggested that it was just learning going on in the kids. Our point of view was that kids ought to have evolved to learn from their mothers because of the shared genes. Strangers, on the other hand, would have more reasons to deceive. So our idea was that children raised by single or unbonded mothers would convey to their offspring that males are not vital to fitness while two-parent family mothers would convey that males are important for successful reproduction.

          In intensive studies of families the biggest difference seems to be that divorced moms have very low regard for their exmates and don’t hesitate to say so, married mothers do not broadcast this message. Interestingly widows are to the other extreme, “losing your dad was the greatest tragedy of our lives”, and so on. This fits with social surveys showing sometimes that father absence effects are reversed in offspring of widows (vs. offspring of divorce.)

          David Rowe always told us he didn’t believe any of it: he thought it was simple genetic transmission. There is some support for this. In California males with the 7-repeat version of the D4 dopamine receptor are more likely to take off and leave their wives and kids. Males with the more active androgen receptor are also more likely to leave. Neither of these finds are replicated to my knowledge so I would not take them to the bank.

          I’ve dreamed for years of getting back into that area since it is so interesting and, as an added bonus, I would not have to look at another DNA sequence, ever.

  3. TWS says:

    My guess is that there are a lot of behavioral genes that are extremely maladaptive in some situations and workable in others. For example, behaviors that are personally aggressive and violent might find a nice niche among traditional west coastal Native Americans. Before Americans started policing everything, paddling to another village, whacking a woman over the head with a paddle and bringing her home for a ‘canoe marriage’ makes sense. You get a wife and later kids. Now, do anything remotely similar and you will wind up in jail.

    Before you could together with your best buddies travel to a nearby village, attack, carry off women and slaves, loot and pillage and if you were good at it or sneaky enough you came out ahead. Now pretty much not a workable career path. Only place that still appears to be a going concern is Africa.

    Being aggressive or at least willing to bluff and taking certain risks makes sense for a warrior oriented society. It doesn’t seem like such a good path for long-term high resource investment farmers.

  4. dave chamberlin says:

    :”that smallish fraction of researchers that are slaves of curiosity”

    I’m not going add anything to this comment, just emphasize it because I like it.

  5. Viral Architect says:

    It is based on the realization that the sort of morphs and game-theoretic balances we see in some nonhuman species are if anything more likely to occur in humans, because our societies are so complex, because the effectiveness of a course of action so often depends on the psychologies of other individuals – that and the obvious fact that people are not the same everywhere.

    It’s not at all obvious to the BBC and its PC apparatchiks:

    “Every one of us has three billion blocks of DNA in our blueprint and 2.997 billion of yours are the same as mine. We might as well be clones.”

    A History of Ancient Britain, Neil Oliver, 2011

    “…the ‘family of man’ is not an empty metaphor, however dysfunctional that family usually is… all humanity has the same needs and preoccupations, fears and hopes. Objects force us to the humble recognition that since our ancestors left East Africa to populate the world we have changed very little.”

    A History of the World in 100 Objects, Neil MacGregor, 2011

    • Tschafer says:

      The state of denial that some otherwise intelligent people live in is just jaw-dropping…

      • Ian says:

        “all humanity has the same needs and preoccupations, fears and hopes. ”

        Less eloquent than, but not much different in meaning to this:

        Hath not a Jew hands, organs,
        dimensions, senses, affections, passions; fed with
        the same food, hurt with the same weapons, subject
        to the same diseases, heal’d by the same means,
        warm’d and cool’d by the same winter and summer
        as a Christian is? If you prick us, do we not bleed?
        If you tickle us, do we not laugh? If you poison us,
        do we not die? And if you wrong us, shall we not revenge?
        If we are like you in the rest, we will resemble you in that.

      • Viral Architect says:

        States of denial are much safer than statements of fact: ask a certain Nobel laureate.

        On October 25, 2007, Watson was compelled to retire as chancellor of the Cold Spring Harbor Laboratory on New York’s Long Island and from its board of directors, after Watson had been quoted in The Times the previous week as saying “[I am] inherently gloomy about the prospect of Africa [because] all our social policies are based on the fact that their intelligence is the same as ours—whereas all the testing says not really.”


      • Ian says:

        Yes, I am familiar with what happened to Watson. The first part of the quote from Neil MacGregor is not necessarily evidence of occupying a state of denial. In a broad sense it is true, or at least true for neurologically-intact human beings.

        The quote from Neil Oliver – ‘we might as well be clones’ – is a much better example of what you’re talking about, because of its incoherence.

  6. hbd chick says:

    “[T]hey argue that adaptations, including behavioral adaptations, are usually generated by complex, co-adapted sets of genes (true), and that such gene complexes would be broken up by sexual reproduction (also true): even if Dad had a set of alleles that made him a natural blacksmith or tap dancer, his kids would never inherit that whole set and the talent should disappear.

    less of a problem if you make sure to inbreed a lot. just sayin’.

  7. Robert Dole says:

    Autism: The Eusocial Hominid Hypothesis

    ASDs (autism spectrum disorders) are hypothesized as one of many adaptive human cognitive variations that have been maintained in modern populations via multiple genetic and epigenetic mechanisms. Introgression from “archaic” hominids (adapted for less demanding social environments) is conjectured as the source of initial intraspecific heterogeneity because strict inclusive fitness does not adequately model the evolution of distinct, copy-number sensitive phenotypes within a freely reproducing population.

    Evidence is given of divergent encephalization and brain organization in the Neanderthal (including a ~1520 cc cranial capacity, larger than that of modern humans) to explain the origin of the autism subgroup characterized by abnormal brain growth.

    Autism and immune dysfunction are frequently comorbid. This supports an admixture model in light of the recent discovery that MHC alleles (genes linked to immune function, mate selection, neuronal “pruning,” etc.) found in most modern human populations come from “archaic” hominids.

    Mitochondrial dysfunction, differential fetal androgen exposure, lung abnormalities, and hypomethylation/CNV due to hybridization are also presented as evidence.

  8. Pingback: linkfest – 02/12/12 « hbd* chick

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