Book Club: Darwin’s Unfinished Symphony, 8, foundations of cooperation

reciprocal altruismThink about the complexities involved in allowing you to do something that nowadays is fairly normal: getting on a plane and fly to another city, across an ocean. It’s not just the sophisticated machinery, ground transportation, the airports, and so forth. It’s the people. Accomplishing such a feat requires the coordinated cooperation of a large number of people who don’t know each other, and don’t know you or why you wish to get on that plane in the first place. This observation sets the stage for the next to the last chapter of Kevin Laland’s Darwin’s Unfinished Symphony: How Culture Made the Human Mind, which we have been discussing for a while now.

The first point Kevin makes in this chapter (n. 11 in the book) is that conventional evolutionary explanations, such as kin selection and other gene-based explanations are insufficient to account for the degree and sophistication of cooperative activities that have characterized human civilization ever since the agricultural revolution. A fully formed theory of cultural evolution is needed, to draw the outlines of which, of course, is Kevin’s goal. Obviously, the idea is not that cultural evolution is independent from its biological counterpart, but rather that it is a novel mode of evolutionary change that resulted from the particular path of biological evolution that hominins happen to have taken.

Two of the factors that make large-scale human cooperation possible are the ability to teach others, and language, which Laland has already argued itself evolved to facilitate teaching. A third factor was the origin of social norms. These specify how individuals are expected to behave within a group, including how to treat individuals who violate norms. Crucially, norms also make possible for people to identify with a particular group, as abiding by its norms carries privileges for in-group members.

Moreover, humans are pretty much the only animals capable of trading goods (there are a few alleged cases in other primates, but they are disputed), and certainly the only ones that arrived at that convenient abstraction we call money. This level of sophistication requires language, and it is both facilitated and made necessary by the existence of division of labor, something that evolved to a high degree of sophistication, again, after the agricultural revolution, which made possible the existence of large and stable groups of humans.

All of this coordination is beneficial thanks to the advantage provided to individuals by indirect reciprocity: I do something for you, you do something for someone else, and at some point down the line another person that has been benefiting from in-group membership does something for me. Like allowing me to safely cross the Atlantic to get from New York to Rome. Repeated bouts of indirect reciprocity require gossip, so that people have a sense of who they can trust and who to stay away from. Needless to say, gossiping, and hence the building and destroying of social reputations, is not possible, again, without language.

Language, in turn, also evolves, quickly generating local dialects. Dialects then rapidly become a mark of local membership, a quick heuristic to tell apart in- from out-group members. They increase within-group cooperation, and likely across-group conflict, which sets the stage for group selection at the cultural level:

“Cultural processes generate plenty of variation among human groups for natural selection to act upon. Extensive data now demonstrate that the differences between human societies result far more from cultural rather than genetic variation. … Symbolic group marker systems, such as rituals, dances, songs, languages, dress, and flags, make it considerably easier for cultures to maintain their identities and to resist imported cultural traits from immigrants, than it is for local gene pools to maintain their identity by resisting gene flow.” (p. 283)

This is something important to keep in mind, as it is intuitive to say that cultures change more rapidly than genes. While this is true if we are talking about mutations (which are, indeed, rare), it is not the case once we consider gene flow and genetic recombination, which happen far more frequently, as Kevin points out, than some types of cultural change.

Laland also remarks on the widespread existence of practices that synchronize the behavior of individuals, like group dancing, or military marches. These activities result in the simultaneous release of endorphins, which in turn promotes within-group bonding. The broader point is that humans evolved a psychology of group behavior that is entirely unknown in other animals, and that cannot be explained on the basis of standard genetic models of evolution. Pace the evolutionary psychologists, of course, for whom we have seen Laland has relatively little patience.

We are reaching the end of this series of posts on Darwin’s Unfinished Symphony. The next and last installment will focus on the cultural evolutionary origin and significance of art.

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44 replies

  1. Thanks, Labnut!

    Although here I’m not trying to be contrarian, just to understand whether I’m misreading the article or misinterpreting/misremembering Massimo’s previous stance. I’m trying to clarify rather than argue.

    Massimo, I agree with your intermediate approach in that there are important differences between biological and cultural evolution, and I also agree with you that cultural evolution is constrained by and made possible by biology.

    Where I perhaps differ from you is that I see interesting parallels between biological and cultural evolution, to the point where I think it may be useful to think of cultural evolution as almost Darwinian, where adaptive cultural practices survive and propagate while maladaptive practices are whittled out by something akin to natural selection.

    In the past, you seemed not to be a fan of this view, but this article seems to be more well-disposed to it. Is that a misreading of the article?

    Evopsych seems to be a different issue.

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  2. ‘memes’ are not like descret units that can be passed on like genes. This is bound to make the Darwinian picture cultural evolution inadequate to say the least.

    Liked by 1 person

  3. Philip: “On the idea that “culture influences biological evolution”, I can see how things like changes in food sources does that, but how does cultural change towards either social democracy or authoritarianism influence biological evolution?”

    For one example, a single book — Rachel Carson’s “The Sea Around Us” — very quickly produced a world-wide change in our attitude toward the environment, which led to cultural changes that are still playing out nearly 70 years later, and (one hopes) will continue to do so for centuries to come, producing changes in living conditions that will affect our genetic makeup by the slower process of biological adaptation.

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  4. DM,

    “Where I perhaps differ from you is that I see interesting parallels between biological and cultural evolution, to the point where I think it may be useful to think of cultural evolution as almost Darwinian, where adaptive cultural practices survive and propagate while maladaptive practices are whittled out by something akin to natural selection.”

    Right, that’s where we depart. I don’t think anyone, including Kevin, has come up with a functional ecological theory of cultural evolution. Without it, the statement that cultural traits evolve is rather trivial, of course they do. And yes they are selected. But why in certain ways rather than others? In biology, we’ve got answers for that question, it’s what makes the theory of natural selection non tautological.

    I’ll pick up on this thread when discussing the last chapter in Kevin’s book.

    Liked by 1 person

  5. Richard Dawkins originally had in mind that memes would have a discrete physical signature in the brain, he says so in later editions of TSG.

    I think that he and most people recognise that this isn’t the case and that memes are sometimes a useful metaphor for the way such cultural units spread rather than a scientific concept in the way a gene is.

    Like

  6. Humans are too culturally plastic for such a theory to exist, in my opinion, Massimo. Given that memes, contra Dawkins and per Cousin, aren’t literal units, there’s nothing to be selected FOR in a cultural version of evolution by natural selection. Plus, modern Homo technologicus has ways of controlling the pseudo-meme pool – advertising, marketing, SEO techniques, Facebook manipulation.

    Liked by 2 people

  7. Philip,
    Are you suggesting that if many in the Trump world are incarcerated, we would become a more socially democratic society?

    Given the way all conversations revert to Trump I think we are creating a new version of Godwin’s Law, Godwin-2 🙂

    More seriously, we are talking about a process of tens of thousands of years. I sincerely hope the Trump phenomenon is not that durable!

    More generally, I tallied all criminal offences of members of Congress(including sanctions that resulted in resignation or dismissal) and found that over the last 100 years Democrats and Republicans were equally represented. Criminal behaviour is, in political terms, an equal opportunity industry.

    Liked by 1 person

  8. Massimo,

    “But why in certain ways rather than others?”

    Positive feedback?

    Somewhat simplistic, but emotion is big on positive re-enforcement and emotion is a big driver of culture.

    Like

  9. Still, I wonder a bit by this sometimes.

    Let
    B = a new biological feature
    C = a new cultural invention

    Was the invention of C due to the evolution of B?
    or
    Was the evolution of B due to the invention of C?

    Or do people just say B and C “coevolved”?

    E.g. (“throwing theory”)
    The invention of stone weapons (C1) led to the evolution of brain circuitry (B1) to support more accurate throwing which led to the invention of recursive language (C2).

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  10. Robin,

    “memes are sometimes a useful metaphor for the way such cultural units spread”

    In which way is the metaphor useful? And what is a cultural unit, exactly?

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  11. Massimo,

    I have expressed myself clumsily, I do not personally find them a useful metaphor, we are better off speaking directly about the way ideas and culture spread.

    I meant that those who still use the term regard them as a useful metaphor rather than reifying them.

    Liked by 2 people

  12. The difficulty of defining memes, even though the ways culture picks up and chews over flavors of the day is quite evident, might go to that dichotomy of flow versus structure. Energy and order.

    An entire area of study, Complexity Theory, grew out of the relationship of order and chaos, but chaos is just how overly ordered people perceive flow. The problem is as soon as it is measured and quantified, it’s no longer flow, but information, aka statistics, randomness, quantum uncertainty, whatever.

    As some old Jazz musician said, when asked what Jazz is; “If you gonna ask, you’ll never know.”

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  13. “And what is a cultural unit, exactly?”

    Cultural units exist over time, the problem would seem to be defining them as objects in space.

    Which would go to the idea of a dynamic as central to their existence.

    Of course, a day is a unit over time, but how does one go about defining it as an object in space?

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  14. I like the selection of memes as a story or a way to think about cultural evolution. It’s a novel and I think useful perspective. I think there is an insight there all right.

    But I’m not in favour of memetics as a science for the reasons Massimo, Robin and Socratic have provided. Memes are vague and mushy and all that. The meme is an intutive concept, not a scientific one. It seems to me that they could well have value in the former role even if they don’t in the latter.

    Liked by 1 person

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