What happens when humans live in an anonymous but densely populated, digitally dependent world, while they are equipped with a brain adapted to living in small hunter-gatherer groups of family and friends roaming sparsely populated open grasslands? Answering this question is the challenge accepted by Ronald Giphart and Mark van Vugt in their book Mismatch: How Our Stone Age Brain Deceives Us Every Day and What We Can Do About It. The concept of mismatch plays an integral role in evolutionary psychology. As these authors define it, mismatch occurs when “as the result of a change in the environment, the survival and reproductive chances of [a] particular species’ individuals diminish” (p. 4) or “when species are faced with a rapidly changing environment to which their hardware and software—their body and mind—are not well adapted” (p. 18).
Giphart and van Vugt argue that humans’ bodies and minds are finely tuned to physical and social environments that existed about 2.5 million to 10,000 years ago. During this period, which evolutionary psychologists refer to as the environment of evolutionary adaptation, ancestral humans faced a multitude of selection pressures that contributed to this fine-tuning process, including “famine, spiders and insect bites, large predators, much internal violence, and high baby and infant mortality” (p. 59). But around 10,000 years ago, humans began to cultivate and permanently settle land and to domesticate animals. This instigated a “Big Bang for humanity” in the form of an agricultural revolution that led to fundamental changes to the physical and social environment of human ancestors. For example, families and communal groups grew in size as access to food became more certain and excess food production enabled large-scale trade. In some cases, the mismatches between ancestral humans’ bodies and minds and their new environment promoted the evolutionary goals of survival and reproduction, and in some cases, they did not.
As their Stone Age brains responded to exaggerated, fake, obsolete, or missing cues from their new environment, humans used their burgeoning technological skills to manipulate that environment in ways that at times undermined their capacity to survive and reproduce. For example, modern humans still have an evolved preference for high-calorie foods, which promoted survivability in ancestral times, when food was scare and sometimes unavailable, but is related to widespread occurrences of life-threatening diseases in current times, when food is abundant and easily acquired. Giphart and van Vugt dedicate the bulk of their book to describing similar missteps across several domains.
The book includes 10 chapters, which describe how evolutionary mismatch may influence modern society along with prescriptions about how such a society may appropriately adjust. The authors start with a succinct but useful prefatory summary of their argument, which they follow in Chapter 1 with an introduction to the concept of mismatch and how it is situated within evolutionary psychology. This includes a discussion of human life in ancestral, preagricultural times and a review of the Darwinian fundamentals of evolution as well as an introduction to evolutionary psychology and the implications of the “Stone Age brain.”
After laying this foundation, Giphart and van Vugt review several consequential mismatches in modern society. Given the primary evolutionary drive to survive and reproduce, it is not surprising that Chapters 2 and 3 focus on health and “a crazy little thing called love.” These chapters look at mismatches related to diet, disease, monogamy, homosexuality, and parenting. Modern humans spend a tremendous percentage of their available time providing for themselves, and Chapter 4 assesses work life and even economic systems in terms of work-life balance relative to evolutionary mismatch.
Humans are highly social animals often forming into groups, and leaders naturally emerge in most groups as groups with leadership tend to perform better. Chapter 5, then, addresses why it is so easy for contemporary humans to choose the wrong leaders at work and in the public sphere with their Stone Age brain. Chapter 6 discusses how modern religiosity, which may be the result of the solace given to human ancestors by a belief in the supernatural as they faced their hazardous environment, can lead people to harmful decisions motivated by their faith. Chapter 7 acknowledges humans’ long history with violence and how mismatched evolutionary forces may result in increased lethality in modern war.
The next two chapters address relatively recently emerging issues. Chapter 8 looks at climate change and how humans’ Stone Age brain, for example, pursues self-interest in the short term through activities such as large-scale energy consumption that make human life more convenient but in the long term produce profound effects on themselves and other animal species. Chapter 9 talks about how virtual reality experiences such as media consumption confound our expertise in in-person communication with misleading mediated experiences.
Finally, Chapter 10 summarizes by offering the “Ten Mismatch Commandments” along with a “tongue-in-cheek and not science-based test” (p. 317) for readers to assess their modern lifestyle’s mismatch with their Stone Age brain.
The chapters on leadership and war are particularly interesting to me as a political scientist. In Chapter 5, the authors note that “those in prehistory who followed the wrong leader with the wrong characteristics simply did not leave any offspring” (p. 167). By the authors’ account, the right leaders in ancestral times understood that the difference between a good and bad decision could be the difference between life and death, used face-to-face leadership that personally built trust in followers, and saw leadership as a physical, masculine endeavor that resulted from leaders’ obligation to cope with violence inside and outside the group. The mismatch between these ancestral preferences and the modern context, in which most leadership is neither death defying, personal, nor physically demanding, leads, for instance, to the modern use of obsolete cues to leader quality, such as a preference for physically formidable (e.g., taller and heavier with greater body mass index) leaders. Research suggests this preference may be related to the ancestral environment, in which physically imposing individuals could assist their allies with acquiring and retaining evolutionarily salient resources such as food and shelter.Reference Murray1
In Chapter 7, Giphart and van Vugt speak of ancestral war as being motivated by the pursuit of status, social capital, and sexual partners. Victorious warriors acquired greater status, which led to more group friendships and exchange partners and, indeed, more reproductive success. This success resulted from the larger pool of available female partners in the newly accessed territory and from the signal sent to potential sexual partners of physical prowess and desirable genes that could be passed on to offspring.Reference Glowacki and Wrangham2 At the same time, ancestral warfare mostly consisted of close-up, small-scale raids and ambushes. The mismatch created in the modern context, then, often results in male-dominated violent conflict that fails to take advantage of the full population of potential warfighters by mostly excluding female fighters. Moreover, it results in escalating lethality as war increasingly takes place at a distance, leaving warriors less exposed to the gritty nature of their duties and therefore less able to empathize with the suffering their adversaries experience during battle.
An issue worth reconsideration for a future edition of the book is the formidably ambitious prescriptions at the end of each domain-specific chapter, in which the authors offer “approaches and ideas to cancel [mismatches] out or turn them into a match” (p. 91). For example, in the chapter related to work and economic systems, the authors recommend a modern version of the ancestral barter economy that would give work “more purpose and meaning” (p. 152). In the chapter addressing war, they argue that peace can be safeguarded by bringing communities closer together through the exchange of marriage partners so that genetic interests are shared. While in the chapter regarding leadership, Giphart and van Vugt suggest that groups and organizations should balance power between leaders and followers as much as possible through mechanisms such as replacing leaders at regular intervals to discourage abuse of power or giving staff a place to gossip about, criticize, and even ridicule their leaders.
These theoretically motivated approaches strongly resonate with me as a social scientist who lives in the world of theory building, but they strike me as unrealistic as an individual living in the real world of modern consumerism, a complex international system, and thin-skinned executives. Given how effectively the social science reviewed in the book stands on its own, the authors should consider dropping the prescriptions in the future if more satisfying approaches to cancelling mismatches cannot be identified.
Overall, Mismatch provides a useful introduction to evolutionary psychology and, more significantly, to why it is important to understand how evolutionary forces can shape human behavior. The book is written in the popular science style, making it most appropriate for a lay audience, but it could also be thought-provoking for undergraduates studying psychology, human behavior, or culture. Professional scholars interested in pursuing the topic, though, will probably want more depth of detail (for an article-length, academic treatment see Li et al.Reference Li, van Vugt and Colarelli3), but for those new to evolutionary psychology who like a broad overview of new topics of academic interest, Mismatch should be a helpful first step.
