Overestimating Your Own Abilities May Be an Evolutionary Boost

By Valerie Ross | September 20, 2011 2:16 pm

What’s the News: We may strive for humility, but we benefit from a little hubris, too, according to a study published last week in Nature. Overconfidence in your abilities can help you triumph in competitions you might not have won otherwise, the study found, and can impart an evolutionary advantage when the potential payoff is high compared to the cost of conflict.

How the Heck:

  • To investigate the effects of overconfidence, the researchers set up a game theory-based computer model. In this model, two individuals could each “decide” (through computer algorithms) whether or not to lay claim to a desired resource. If they both claimed it, the stronger individual won the resource, but both individuals incurred a small cost, the toll of competition. If only one individual decided to go after the resource, that individual got the prize without incurring a cost from conflict; if neither did, neither got it.
  • Each competitor decided whether or not to claim the resource based on what they knew of their abilities compared to their opponents’. But, as is usually the case in real life, the individuals didn’t have a complete, unbiased view of the situation: The model varied whether each individual was overconfident or underconfident in their own abilities, and how uncertain they were about their competitors’ abilities.
  • The computer simulation went through thousands of generations of these competitions. To mimic natural selection, strategies with high fitness—meaning they resulted in more rewards, fewer costs—were passed down to the next generation.
  • The researchers found that being overconfident in one’s own abilities paid off, and the trait got passed down. In particular, being overconfident was an advantage when there was uncertainty about an opponent’s strength, and when the reward for winning was high relative to the cost of competing. In other words, being overconfident helped competitors make the right—that is, the most profitable—decision [$].
  • When the researchers tweaked the model to have three competitors instead of two, the same effect appeared: Overconfidence still led to success.

What’s the Context:

  • A large body of research has shown that people are routinely overconfident, overestimating their financial acumen, leadership skills,driving abilities, and even attractiveness. If overconfidence sometimes confers an evolutionary benefit, as this study suggests, that could help explain why it’s so widespread.
  • But, the researchers point out, these findings only apply to conflict and overconfidence on a small scale. Our tendency to have too much faith in our abilities may help explain current events caused in part by overconfidence—wars in which one side overestimated their power, the recent economic collapse—but it doesn’t have the same benefit in large, complex societies that it might in one-on-one competition. Overconfidence is like the body’s tendency to crave extra calories, the researchers say: an advantage at the time modern humans evolved, but sometimes a pitfall in today’s world.


  • Dominic D. P. Johnson & James H. Fowler. “The evolution of overconfidence.” Nature, September 15, 2011. DOI: 10.1038/nature10384
  • Matthijs van Veelen & Martin A. Nowak. “Evolution: Selection for Positive Illusions.” Nature, September 15, 2011. DOI: 10.1038/477282a
CATEGORIZED UNDER: Human Origins, Mind & Brain
  • kirk

    Maybe I don’t get it but this seems like Taleb’s Fooled by Randomness example. Take 100 subjects and pair them off in a best of 3 coin flipping contest. The 50 winners advance to the next round, the 25 winners advance… At the end the subject with the ‘winning strategy at coin flipping’ struts up to the stage and accepts his trophy… His off-spring have genes ‘for’ winning coin flip contests. Or not.

  • Brian Too

    This piece made me think of a perceptive article I read this week, by David Brooks.


    I think his overarching point was that the time needed to change complex systems, where multiple players must agree and coordinate action, is consistently underestimated by the players.

    Related to the above, I think, by the fact that the players perhaps also don’t have complete information about their situation. Of course if the problem is truly one of overconfidence, then complete information would not really help, would it? At best it might be part of a solution, but it could not be a full solution by itself.

  • TheCritic


    It may seem like that, but it’s not. The results of this study are not showing things by random chance. A real world example of why something like this might have evolved would resemble maybe a hunter in the past who looked at a bear and thought he could kill it for lots of food. Clearly, bears have a quite distinct physical advantage over us in every department. A rationally thinking person at the time (without guns or whatever tools we may use today besides a spear) would look at that situation and see it as a poor idea and not even try (even though they may have been able to). An underconfident person, as well. Thus, neither have food. An overconfident person that looked at that scenario and actually was able to kill the animal (the important part) now has food for a long time and can devote time to increasing his tools or whatever he may wish to do. That would be quite attractive to primitive mates (the ability to care for a mate/family).

  • http://www.dpughphoto.com Dorothy Pugh (@bergamotley)

    It’s funny how many different ways we see “overconfidence:” 1) ambition, 2) courage, 3) moxie, 4) nerve, 5) being “uppity” or 6) just plain crazy. But here context is everything. If you’re risking your life or, worse, those of others, for poorly-thought-through reasons, it’s a bad thing. If you’re recklessly hurting someone’s reputation by presenting ungrounded speculation as fact, that’s also bad.

    But suppose you’re taking on a tough orchestral piece in an educational setting or working extra hours to come up with a general solution to a messy problem that’s tying your organization in knots? Suppose you’re attempting to learn a new skill that the local experts say you shouldn’t attempt because existing data say you’ll fail? Suppose you’re the only one willing to step up to the plate when everyone is shrinking back from a necessary task that threatens to be tiring or humiliating? Or if you’ve got a bright idea for a tool or process that might succeed in making society better off, or just might wind up being a waste of your time and energy?

    Over the years, I’ve seen people confuse guts and irresponsibility. When you gamble on something you don’t understand and/or can’t control, that’s giddiness. When you gamble that you’ll finish cleaning up a huge mess that no one else wants to touch with a ten-foot pole, that’s pretty noble, I think. We need to recognize the difference!


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