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The Righteous Mind
Chapter Nine - Why Are We So Groupish? - Continued
Exhibit C: Genes and Cultures Coevolve
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p208 It’s only around 600,000 or 700,000 years ago that we begin to see creatures who may have crossed over [this Rubicon of shared intentionality]. The first hominids with brains as large as ours begin appearing in Africa and then Europe. They are known collectively as Homo heidelbergensis and they were the ancestors of Neanderthals as well as of us. At their campsites we find the first clear evidence of hearths, and of spears... These people made complex weapons and then worked together to hunt and kill large animals, which they brought back to a central campsite to be butchered, cooked, and shared.
p209 Homo heidelbergensis... had cumulative culture, teamwork, and a division of labor. They must have had shared intentionality, including at least some rudimentary moral matrix that helped them work together and then share the fruits of their labor... From that point onward, people lived in an environment that was increasingly of their own making.
The anthropologists Pete Richerson and Rob Boyd have argued that cultural innovations (such as spears, cooking techniques, and religions) evolve in much the same way that biological innovations evolve, and the two streams of evolution are so intertwined that you can’t study one without studying both. (Note 65. There are two major differences: (1) cultural innovations spread laterally, as people see and then copy an innovation; [the wheel is the best example] genetic innovations can only spread vertically, from parent to child, and (2) cultural innovations can be driven by intelligent designers -- people who are trying to solve a problem; genetic innovation happens only by random mutation. See Richerson and Boyd 2005, Dawkins 1976 first popularized the notion of cultural evolution being like genetic evolution with his notion of “memes,” but Richerson and Boyd developed the coevolutionary implications more fully.) For example, one of the best-understood cases of gene-culture coevolution occurred among the first people who domesticated cattle... Any individual whose mutated genes delayed the shutdown of lactase production had an advantage. Over time, such people left more milk-drinking [into adulthood] descendants than did their lactose-intolerant cousins... Genetic changes then drove cultural innovations as well: groups with the new lactase gene then kept even larger herds, and found more ways to use and process milk, such as turning it into cheese. These cultural innovations then drove further genetic changes...
p210 If cultural innovations... [like this] can lead to genetic responses... [like this] then might cultural innovations related to morality have led to genetic responses as well? Yes...
According to... [Richerson and Boyd’s] “tribal instincts hypothesis,” human groups have always been in competition to some degree with neighboring groups. The groups that figured out (or stumbled upon) cultural innovations that helped them cooperate and cohere in groups larger than the family tended to win these competitions (just as Darwin said).
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p211 ...once some groups developed the cultural innovation of prototribalism, they changed the environment within which genetic evolution took place. As Richerson and Boyd explain:
Such environments favored the evolution of a suite of new social instincts suited to life in such groups, including a psychology which “expects” life to be structured by moral norms and is designed to learn and internalize such norms; new emotions such as shame and guilt, which increase the chance that the norms are followed, and a psychology which “expects” the social world to be divided into symbolically marked groups.
In such prototribal societies, individuals who found it harder to play along, to restrain their antisocial impulses, and to conform to the most important collective norms would not have been anyone’s top choice when it came time to choose partners for hunting, foraging, or mating. In particular, people who were violent would have been shunned, punished, or in extreme cases killed.
This process has been described as “self-domestication...”
...early humans domesticated themselves when they began to select friends and partners based on their ability to live within the tribe’s moral matrix... Domesticated animals (including humans) are more childlike, sociable, and gentle than their wild ancestors.
These tribal instincts are a kind of overlay, a set of groupish emotions and mental mechanisms laid over our older and more selfish primate nature. It may sound depressing to think that our righteous minds are basically tribal minds, but consider the alternative. Our tribal minds make it easy to divide us, but without our long period of tribal living there'd be nothing to divide in the first place. There’d be only small families of foragers -- not nearly as sociable as today’s hunter-gatherers -- eking out a living and losing most of their members to starvation... The coevolution of tribal minds and tribal cultures didn’t just prepare us for war; it also prepared us for far more peaceful coexistence within our groups, and, in modern times, for cooperation on a vast scale as well.
It is interesting to observe here the comparative advantage the Allies had over the Axis powers in WW2 (especially Japan and Germany) when it came to cooperation. In Japan, even the Army and Navy sub-tribes could not cooperate effectively.
...Even if group selection played no role in the evolution of any other mammal, (Note 75. Other than two species of African mole rats [you don't want to see them], which are the only mammals that qualify as eusocial. The mole rats achieve their eusociality in the same way as bees and ants -- by suppressing breeding in all except for a single breeding couple, such that all members of the colony are very close kin... [In a wolf pack it is sometimes only the alpha male and female that mate (this depends on how large their territory is). This really isn’t a good alternative since the role of alpha will shift over time from one individual to another.]) human evolution has been so different since the arrival of shared intentionality and gene-culture coevolution that humans may well be a special case...
Exhibit D: Evolution Can Be Fast
p212 ...our ancestors spread out from Africa and the Middle East around 50,000 years ago... But did gene-culture coevolution stop at that point? Did our genes freeze in place, leaving all later adaptation to be handled by cultural innovation? ... In an interview in 2000, the paleontologist Stephen Jay Gould said that ‘natural selection has almost become irrelevant in human evolution” because cultural change works “orders of magnitude” faster than genetic change. He next asserted that “there’s been no biological change in humans in 40,000 or 50,000 years. Everything we call culture and civilization we’ve built with the same body and brain.”
p213 ... But is 12,000 years really just an eye blink in evolutionary time? Darwin didn’t think so; he wrote frequently about the effects obtained by animal and plant breeders in just a few generations.
Not to mention those moths.
[Studies with foxes and chickens confirm that traits can change in just thirty generations with foxes and within six generations with chickens. For humans, thirty generations equals six hundred years.]
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p215 The actual speed of genetic evolution is a question that can be answered with data, and thanks to the Human Genome Project, we now have that data... Genes mutate and drift through populations, but it is possible to distinguish such random drift from cases in which genes are being “pulled” by natural selection. The results are astonishing, and they are exactly the opposite of Gould’s claim: genetic evolution greatly accelerated during the last 50,000 years. The rate at which genes changed in response to selection pressures began rising around 40,000 years ago, and the curve got steeper and steeper after 20,000 years ago. Genetic change reached a crescendo during the Holocene era, in Africa as well as in Eurasia.
...[There is also] a gene that changed the blood of Tibetans so that they could live at high altitudes... If genetic evolution was able to fine-tune our bones, teeth, skin, and metabolism in just a few thousand years as our diets and climates changed, how could genetic evolution not have tinkered with our brains and behaviors as our social environments underwent the most radical transformation in primate history?
p216 I don’t think evolution can create a new mental module from scratch in just 12,000 years, but I can see no reason why existing features -- such as the six foundations... or the tendency to feel shame -- would not be tweaked if conditions changed and then stayed stable for a thousand years. For example, when a society becomes more hierarchical or entrepreneurial, or when a group takes up rice farming, herding, or trade, these changes alter human relationships in many ways, and reward very different sets of virtues. Cultural change would happen very rapidly -- the moral matrix constructed upon the six foundations can change radically within a few generations. But if that new moral matrix then stays somewhat steady for a few dozen generations, new selection pressures will apply and there could be some additional gene-culture coevolution. (Note 86. Some readers may fear, as perhaps Gould did, that if genetic evolution continued during the last 50,000 years, then there could be genetic differences among the races. I think such concerns are valid but overstated. There were few selection pressures that ever applied to all Europeans, or all Africans, or all Asians. Continent-wide races are not the relevant units of analysis for the evolution of morality... And... even if there do turn out to be ethnic differences in moral behavior that are related to genetic differences, the genetic contribution to such behavioral differences would likely be tiny compared to the effects of culture... )
I don't think Haidt did a particularly good job of allaying those fears, but they are not mine anyway. What interests me is the very real concern that individual people will never be entirely comfortable or happy outside the particular tribal context their genes coevolved in. I think I've mentioned before the strange feeling of being "home" I felt on my one visit to Scotland, especially when I was near the area where I have since learned my great grandfather migrated from. This is not just a political problem for melting pot societies like the United States.
...Whatever the [catastrophic] cause, we know that almost all humans were killed off at some point during this period. [70,000 to 140,000 years ago.] Every person alive today is descended from just a few thousand people who made it through one or more population bottlenecks.
It’s Not All About War
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p217 ...Group selection does not require war or violence. Whatever traits make a group more efficient at procuring food and turning it into children makes that group more fit than its neighbors. Group selection pulls for cooperation, for the ability to suppress antisocial behavior and spur individuals to act in ways that benefit their groups. Group-serving behaviors sometimes impose a terrible cost on outsiders (as in warfare). [The history of Rome.] But in general, groupishness is focused on improving the welfare of the in-group, not on harming an out-group.
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p219 ...We humans have a dual nature -- we are selfish primates who long to be a part of something larger and nobler than ourselves. We are 90 percent chimp and 10 percent bee. If you take that claim metaphorically, then the groupish and hivish things that people do will make a lot more sense. It’s almost as though there’s a switch in our heads that activates our hivish potential when conditions are just right.
(Note 93. The numbers 90 percent and 10 percent should not be taken literally. I am just trying to say that... a substantially smaller portion of human nature was forged by group-level selection... Of course the psychology of bees has nothing in common with human psychology -- they achieve their extraordinary cooperation without anything like morality or the moral emotions. I’m merely using bees as an illustration of how group-level selection creates team players.)
Fine. I’ll accept this metaphorically. Since we seem to be unique in being ultrasocial while breeding independently, it is impossible to come up with a perfect analogy.
When talking about how quickly we can evolve, I'm surprised he didn’t mention the way disease causes genetic change. My favorite example being the House of Windsor (née Hanover) which has flourished in their British niche because they were Protestant and resistant to the more fatal forms of smallpox which wiped out their predecessors.
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