Altruism and Risk-Taking: Kinda Heritable


Economists are getting into the twin-study game more often. The latest entry is forthcoming in the Harvard-MIT run Quarterly Journal of Economics. They ran tests on a bunch of Swedish twins, tests that involved real money. The goal: See how altruistic they were (how much money did they share with a pro-homeless charity?) and see how risk-tolerant they were (how big does the reward have to be before they’d take a risky gamble?).

Key quote:

[W]e have used standard behavior genetic techniques to decompose variation in preferences for giving and risk-taking into environmental and genetic components. We document a significant genetic effect on risk taking and giving, with genes explaining approximately 20% of phenotypic variation in the best fitting models. The estimated effect of common environment, by contrast, is smaller.

So E>A>C, a common result. Since economists have spent a fair amount of time arguing for the social construction of preferences, it’s good to have some evidence that shared family environment–presumably one important kind of “social construction”–apparently has only a modest association with routine economic preferences.

Note: This is the same group of researchers that found that 40% of “responder” behavior in an ultimatum game was heritable.

Conclusions: 1. The Swedish Twin Registry is a treasure. 2. Responder behavior (basically, willingness to punish even when it’s expensive to punish) seems about twice as heritable as risk-taking and altruism. We’re only going on two studies here, but that’s an interesting result: Perhaps “Desire for justice/revenge” is more heritable than “Fear of loss” and “Kindness.”



  1. Responder behavior sounds like altruistic punishment. It has been suggested that populations descended from northern hunter-gatherers are high on this trait(1).The people whose steppe – tundra evolved ancestors ended up in Sweden after following the reindeer north as the ice over Scandinavia melted may have a very strong tendency to punish any behaviour they perceive as freeloading. This may have been advantagous in the context where lack of resources meant small tribal groups. Anyway, I think this tendency might be particularly strong in Sweden and rather weak outside Europe, to the extent that it is heritable at least. Possibly the lavish welfare with imposition of high taxation, implacable anti-drug enforcement and (according to Steve Sailer) state approved first names are examples of Swedish psychic quirks. Sweden’s laws certainly seems to be very moralistically disapproving towards any trace of bias or prejudice, perhaps it is regarded as a despicable form of backsliding not to be liberal.  
    1)What Makes Western Culture Unique?

  2. Maybe, the “altruistic punishment” trait apperar to be more ereditable because it is more useful than the “altruistic” and the “risk taking” traits. 
    The usefulness is linked to the ability of a population rich of altruistic punishers to grow more cooperative by controlling the number of freeriders, where a population too rich of altruistic people will have more problems to control freeriders. 
    So, for the population is better to have high ereditable “altruistic punishment” traits than “altruistic” traits or “risk taking” traits.

  3. Tod, wouldn’t we expect low heritability if what you are saying is true?

  4. David, if you mean that altruistic punishment has come to be maladaptive I think the author of the article I referenced would agree.