Zero Sum Games and Evolution

I’m reading (and thoroughly enjoying) Alchemy, by Rory Sutherland. My thanks to Shashikant Kore for the recommendation.

It is a light but thought-provoking read, and if you are a relatively fast reader, you could finish it fairly quickly, even in one sitting. But I’ve resisted the urge to do so, and I read a little bit every day. It makes the process more enjoyable, and I also enjoy thinking about what I’ve read until I pick up the book again.

I may write a fuller review of the book later on (knowing me, don’t hold your breath), but for now, I wanted to talk about a particular excerpt that I read a couple of days ago:

For instance, as Geoffrey Miller notes, a tribe where males advertised their hunting prowess by conspicuously sharing meat from their kills would prosper, as a result of economically irrational behaviour. On the other hand, an otherwise identical tribe whose males signalled their strength by violently fighting each other would suffer as a consequence: even the eventual winners of these contests might end up badly wounded and with a lower life expectancy. The first one is a positive sum game, while the other is anything but. An extreme pessimist might suggest that, although competition for wealth markers is wasteful and harmful to the planet, it is a lot less harmful than many other forms of intergroup or interpersonal competition.

Alchemy, by Rory Sutherland, Location: 2,746, Kindle Edition

Such a wonderful paragraph and so much to talk about.

  1. Showing me the phrase ” positive sum game” is like showing a red rag to a bull. Of course I’m going to bite!
  2. What is the context here? This risks become a very long post, but I will provide a set of links here for background. Please read them later, if you’re so inclined.
    • Read about sexual selection: the idea that “for a gene to persist, the body that carries it needs not only to survive but to reproduce”.
    • Read about Fisherian runaway selection: “the exaggerated secondary sexual characteristics of animals could evolve by means of a runaway evolutionary process in which an initial small adaptive dimorphism was then further developed into a much more heightened trait by an ongoing interactive combination of female selective choice and increased male advantage.”
    • Long story short, how do genes persist across generations of species? By getting members of this species to reproduce. How should these genes “get” these members to reproduce? By being able to signal their worthiness. How should one signal one’s worthiness? Peacocks do so with their tail feathers, bullfrogs do it by being truly impressive croakers.
  3. And Rory Sutherland asks us to imagine a tribe of humans in which one’s worthiness is signaled by “conspicuously sharing meat from their kills”. That is, awesome hunters are able to hunt bigger and better animals, and these awesome hunters will find it easier to find mates, the more (and more conspicuously) they share the spoils from their hunts. Better hunters will get better mates, and the next generation will therefore produce even better hunters, and “soon” we will have a tribe of mostly (only?) awesome hunters.
  4. Rory Sutherland also asks us to imagine a tribe of humans in which one’s worthiness is signaled by “violently fighting each other”. Imagine the two best hunters in a tribe showing their worthiness not by laying out the proverbial feast, but by fighting each other to the death. Sure, the fittest will survive, but note two things. First, the slightly weaker hunter is dead. That’s bad news for the tribe in both the short and the long run. Second, the stronger hunter survives, but at a very high cost. Maybe the stronger hunter can’t survive himself for much longer after the fight. Or can’t reproduce. Or can’t hunt. He has “won”, but at what cost?
  5. Which approach is better? Obviously the conspicuous sharing of the spoils from hunts approach. This approach is the non-zero-sum approach (or the positive sum approach) if you prefer. This sort of competition gets more food for the tribe, and leaves the tribe with healthy hunters tomorrow, and lots of young hunters with possibly even more talent in the next generation. For a hunter to win at arranging the best feast, other hunters (and the rest of the tribe) don’t have to lose – in fact, they win!
    The other approach leaves you with dead or badly injured hunters – for a hunter to win, all other hunters (and therefore, eventually, the tribe) have to lose.
  6. As an economist, I have to protest the use of the phrase “as a result of economically irrational behaviour”. Rory Sutherland uses this phrase in the context of hunters sharing their meat. But why should this be economically irrational behaviour? In fact, over time, this may well end up being economically rational behavior! People who take only the short term view are being irrational, sure. But that simply behooves us to accept the economic principle that Time Matters. Take the long term view, not the short term one! And once you do so, sharing ain’t irrational at all!
  7. But in general, I love the point that positve-sum games are beneficial not just in and of themselves, but also from an evolutionary perspective. Very cool!
  8. “An extreme pessimist might suggest that, although competition for wealth markers is wasteful and harmful to the planet, it is a lot less harmful than many other forms of intergroup or interpersonal competition”. The opportunity cost of fancy yachts, in other words, is death and destruction.
    Imagine alpha males who signal how awesome they are by invading countries or killing each other in the name of religion, for example. What a horrible world that would be. No?

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