Evolutionary Mismatch

How our stone age brain deceives us every day (and what we should do about it).

Posted Apr 02, 2018

Are we humans perfectly fitted to the world we live in today? Evolutionary psychology suggests this may not be the case. An important concept in evolutionary psychology is mismatch (1). Evolutionary mismatch occurs when the environment that organisms are adapted to, via a slow process of biological evolution, changes so quickly and intensely that it hinders these organisms to fulfill their reproductive needs.

Take an example from nature. Deforestation has changed the habitats of many species so profoundly that they are no longer able to thrive, or even survive, in these altered environments. Just consider the alarming reports of the decline in Borneo's orangutans' populations, the result of human interference that is destroying their habitats. Mismatches such as these are forced upon a species (think of the meteorite strike that called off the dinosaurs). Other mismatches occur because environmental changes hijack psychological systems such that individuals of a species make the wrong kinds of choices.

These are the kinds of mismatches that describe the human condition. In our new book Mismatch: How Our Stone Age Brain Deceives Us Every Day (And What We Can Do About It), we use mismatch theory to understand all kinds of ills of modern society, from depression to drug-abuse, from bottle-feeding to bad parenting, and from toxic leadership to stress in the workplace (2). The basic tenet of mismatch theory is that if we have two options, A and B, mismatch occurs when we prefer option B, where option A would be better for us in the long run. Take the classic example of food-intake. Humans have an evolved preference for high-calorie foods—this preference helped them survive in ancestral environments where food supplies were short. Yet, in the modern world, high-calorie foods are abundant and easy to get, and so humans would be better off showing some restraint in what they eat and how much. Yet many of us lack in self-control, which was not needed in our ancestral environment, and the result is an epidemic of obesity, diabetes, and heart disease. 

Mental health problems may also result from mismatch. For instance, postpartum depression may be the result of living in an environment where the physical (diet, sunlight exposure) and social resources (a tight family network) are lacking to cope with the increasing demands of child care. Postpartum depression rates in the U.S. are lower, for instance, among young mothers from relatively poor but supportive families than those from more privileged backgrounds (this phenomenon is also known as the Latina paradox) (3).

In addition to health problems, mismatch can also cause problems within relationships. For instance, in a modern environment, people are exposed to so many alternative partners—either real or imagined (via Internet)—that they find it increasingly hard to maintain a long-term committed romantic relationship. Psychological experiments show that when people have exposed to a dozen faces of attractive opposite-sex partners they value their own relationship partner less (1).

Problems in the modern workplace may also result from the mismatch as our special collection of essays of The Evolution Institute shows (4). More than 99 percent of human evolution took place in small-scale societies, hunter-gatherer groups of 50-150 individuals that roamed the savannah looking for food and safety. These were societies without bosses, production targets, and pension plans. There was no strict separation between work and private life. Only since the agricultural revolution, the last 1 percent of human evolution, did human societies grow in scale and complexity and this produced toxic work arrangements for many.

The agricultural revolution, and thereafter the industrial revolution, produced inequalities in health, income, and decision-making power, and a marked separation between one’s private and work life—conditions unknown to our ancestors. In small-scale societies, trust and cooperation are established on the basis of frequent face-to-face interactions. Yet these interactions are increasingly lacking as remote workplace arrangements have become the norm. Small-scale societies have no formal leaders and status and power differences between individuals were minimal. Yet modern organizations have CEOs with excessive pay schemes and middle managers who in principle can control all aspects of your working life. The result is job stress, job alienation, and the potential for corruption and power abuse (5). Work also causes many novel stressors like handling deadlines and dealing with temporary contracts that were unknown to our ancestors, these are stressors that our immune system is poorly adapted to (6).

So, what to do about evolutionary mismatch? We offer a number of suggestions. First, we should find out, on a case-by-case basis, to what extent our modern social and work life is mismatched. Second, we don’t have to go back to living in a cave. Yet we should acknowledge that human-evolved psychology poses constraints on the way we structure our lives and how we deal with new environmental challenges. Third, we should design our lives in such a way that they either work with or if this is impossible, work around our ancestral small-scale psychology.

Health and sustainable food options should be easily available for all and they should be tasty and cheap. We should design our lives to have frequent face-to-face interactions. We should lead, not manage people. And our work environments must offer plenty of room for physical movement, informal socializing and interactions with nature (our ancestors were always surrounded by green). It is time to heed the lessons of our deep history.


1. Li, N. P., van Vugt, M., & Colarelli, S. M. (2017). The Evolutionary Mismatch Hypothesis: Implications for Psychological Science. Current Directions in Psychological Science, 0963721417731378.

2. Giphart, R., & Van Vugt, M. (2018). Mismatch: How our stone age brains deceive us every day and what we can do about it. London: Robinson.

3. Hahn-Holbrook, J., & Haselton, M. (2014). Is postpartum depression a disease of modern civilization? Current directions in psychological science, 23(6), 395-400.

4. This View of Business: How Evolutionary Thinking Can transform the workplace. Special issue with collections from scholars and practitioners on the nexus of evolutionary and organizational sciences.  

5. Van Vugt, M., & Ahuja, A. (2011). Naturally selected: The evolutionary science of leadership. New York: HarperBusiness.

6. Van Vugt, M., & Ronay, R. (2013). The evolutionary psychology of leadership: Theory, review, and roadmap.  Organizational Psychology Review, 2041386613493635.

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