Evolutionary Psychology strongly rejects the view of the human mind as tabula rasa, and avers instead that it is content rich and biased. The human brain, and all of its psychological mechanisms, are adapted to the EEA (environment of evolutionary adaptedness) and are therefore biased in favor of viewing and responding to the world as if it were still the EEA. The psychological mechanisms we possess in our brain today are still the same psychological mechanisms that we possessed in the EEA, just as our hand and pancreas are still the same as they were 10 000 years ago. It is not impossible to overcome this bias through conscious effort, but it is often difficult. This is why we still respond to sweets and fats today as if we still lived in the EEA where such high-calorie foods were rare and malnutrition was an imminent problem for survival, and we have the strong urge to consume a large quantity of sweets and fats (even though many of us can consciously overcome the urge) (Barash 1982, pp. 144–147). It is my contention that the human brain has unconscious difficulty comprehending and dealing with entities and situations that did not exist in the EEA.
For instance, one of the entities that we know for sure did not exist in the EEA is television. The fundamental principles of EP would therefore imply that humans have difficulty recognizing and dealing with TV. This indeed appears to be the case. People who watch certain types of TV shows are more satisfied with their friendships, just like they are if they have more friends or spend more time socializing with them in real life. It appears that the human brain has difficulty distinguishing between real friends and imaginary ones they see on TV, because it did not exist in the EEA (Kanazawa, 2002). It is this fundamental observation, that our brain and its psychological mechanisms are strongly biased to view and respond to the environment as if it were still the EEA, which leads to the Savanna Principle.
https://personal.lse.ac.uk/kanazawa/pdfs/MDE2004.pdf
https://personal.lse.ac.uk/kanazawa/
Kanazawa (2004a) proposes that the human brain may have difficulty comprehending entities and situations that did not exist in the ancestral environment, and, as one empirical demonstration of this Savanna Principle, Kanazawa (2002) shows that people who watch certain types of TV shows are more satisfied with their friendships, suggesting that they may have difficulty distinguishing TV characters from real friends. In an entirely different line of research, Kanazawa (2004b) advances an evolutionary psychological theory of the evolution of general intelligence, which proposes that general intelligence evolved in order to handle evolutionarily-novel problems. The logical convergence of these two separate lines of research leads to the prediction that the human difficulty in dealing with evolutionarily-novel stimuli interacts with general intelligence, such that the Savanna Principle holds stronger among the less intelligent than among the more intelligent. Further analyses of the U.S. General Social Survey demonstrate that less intelligent men and women may have greater difficulty separating TV characters from their real friends than more intelligent men and women.
https://personal.lse.ac.uk/kanazawa/pdfs/JCEP2006.pdf
https://personal.lse.ac.uk/kanazawa/
…The human species did not evolve in modern cities or even in villages. An estimated 99% of the evolutionary history of Homo sapiens took place in an environment resembling today's African savannah. Throughout this period of over 2 million years, our ancestors lived in small nomadic groups of hunter-gatherers. It was only 10 000 years ago that some of them started to become sedentary and to practice agriculture.
The key idea in evolutionary psychology is that the human brain should be seen as a vast set of specialized units or “modules” adapted to the problems that our hunter-gatherer ancestors encountered in their environment (see sidebars).
In other words, instead of regarding the human brain as a machine that can learn anything, evolutionary psychologists see it more like a Swiss Army knife: a collection of various tools, each of which performs a specific function.
https://thebrain.mcgill.ca/flash/d/d_05/d_05_p/d_05_p_her/d_05_p_her.html
The earliest ancestors of today's humans (for instance, Homo habilis, who appeared about 2.5 million years ago) evolved for thousands of years in an environment very different from our own. The term "environment of evolutionary adaptedness (EEA)" is used to refer to these various constraints to which our hunter-gatherer ancestors were subject on the savannah .
Some of these constraints were physical, such as the need to keep warm, to find enough food, and to avoid disease and predators. But even more important were the social constraints, such as the need to maintain reciprocal relationships with other individuals, to avoid cheaters, and to secure a good rank in the hierarchy, as well as the need to find a partner with whom to reproduce and to form sufficient ties with that partner to raise the resulting young.
Consequently, in addition to selecting the anatomical characteristics best suited to the physical environment, evolution also selected the psychic mechanisms that provided our ancestors with the best pay-off in these social situations. Evolutionary psychology thus sees the modern human brain as being composed of modules that specialize in problem-solving and that have thus enabled the species to optimize its reproductive success.
Thus we see that our brain was not “selected” to live in the urban, technological environment that we know today. For some brain functions, this does not matter. But for others, such as the chronic activation of the brain's alarm system , the consequences for the organism may be disastrous . The corollary of this might be the calming effect that city dwellers experience when they go out into the country, an environment much more similar to the one in which our species evolved.
https://thebrain.mcgill.ca/flash/i/i_05/i_05_p/i_05_p_her/i_05_p_her.html
The Savanna Principle - What the human brain can and cannot comprehend, and why. Satoshi Kanazawa, Feb 28, 2010
One of the fundamental assumptions of evolutionary psychology is that there is nothing special about the human brain. It is an evolved organ, just like the hand or the pancreas or any other part of the human body.
Just like all the other parts of the human body, the brain – and all the evolved psychological mechanisms in it – are designed for and adapted to the conditions of the ancestral environment in which they evolved, not necessarily to the current environment. This principle holds for both psychological adaptations, like evolved psychological mechanisms, and physical adaptations, like the eye, the vision, and the color recognition system.
What color is a banana? A banana is yellow in the sunlight and in the moonlight. It is yellow on a sunny day, on a cloudy day, on a rainy day. It is yellow at dawn and at dusk. The color of the banana appears constant to the human eye under all these conditions, despite the fact that the actual wavelengths of the light reflected by the surface of the banana under these varied conditions are different. Objectively, they are not the same color all the time. However, the human eye and color recognition system can compensate for these varied conditions because they all occurred during the course of the evolution of the human vision system, and can perceive the objectively varied colors as constantly yellow.
So a banana looks yellow under all conditions, except in a parking lot at night. Under the sodium vapor lights commonly used to illuminate parking lots, a banana does not appear natural yellow. This is because the sodium vapor lights did not exist in the ancestral environment, during the course of the evolution of the human vision system, and the visual cortex is therefore incapable of compensating for them.
Fans of the 1989 James Cameron movie The Abyss may recall a scene toward the end of the movie, where it is impossible for a diver to distinguish colors under artificial lighting in the otherwise total darkness of the deep oceanic basin. Regular viewers of the TV program Forensic Files and other real-life crime shows may further recall that eyewitnesses often misidentify the colors of cars on freeways, leading the police either to rule in or rule out potential suspects incorrectly. Highways and freeways are often lit with sodium vapor lights and other evolutionarily novel sources of illumination.
The same principle that holds for physical adaptations like the color recognition system also holds for psychological adaptations. Pioneers of evolutionary psychology all recognized that the psychological adaptations are designed for and adapted to the conditions of the ancestral environment, not necessarily to the conditions of the current environment. I call these observations the Savanna Principle: The human brain has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment. Other evolutionary psychologists call the same observation the evolutionary legacy hypothesis or the mismatch hypothesis.
One example of the Savanna Principle in action is the fact that individuals who watch certain types of TV shows are more satisfied with their friendships, just as they are if they had more friends or socialized with them more frequently. It makes perfect sense that people who have more friends and socialize with them more frequently are more satisfied with their friendships than those who don’t have as many friends or socialize with them as frequently. And they are. What’s interesting is that the same thing happens if they watch more TV. From the perspective of the Savanna Principle, this is probably because realistic images of other humans, such as television, movies, videos, DVDs, and photographs, did not exist in the ancestral environment, where all realistic images of other humans were other humans. As a result, the Savanna Principle suggests that the human brain may have implicit difficulty distinguishing their “TV friends” – the characters they repeatedly see on TV shows – and their real friends.
Another example, discussed extensively in a previous post, is the fact that, when experimental psychologists deliberately create a situation where people earn money when they are ostracized and lose money when they are included, people still feel happy when they are included (and lose money) and hurt when they are excluded (and make money). While this makes no sense from a purely economic perspective, it is perfectly consistent with the Savanna Principle. Throughout the course of human evolution, exclusion from a group was always costly and inclusion was always beneficial. These two factors always covaried throughout evolutionary history, because there were no evil experimental psychologists in the ancestral environment to manipulate them independently. There were no such things as beneficial exclusion or costly inclusion, and the human brain cannot therefore comprehend them. It implicitly assumes that all inclusion is beneficial and all exclusion is costly.
So it appears that the human brain indeed has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment, as the Savanna Principle suggests. If you look around, you will realize that virtually nothing in your current environment existed in the ancestral environment. In fact, I believe there are only four entities in our current environment that existed in the ancestral environment: men, women, boys, and girls. If you are outside, you may be tempted to include such natural features as trees, mountains, and rivers, but unless you are on the African savanna, they are not the same trees, mountains, and rivers that existed in the ancestral environment. There are more situations and relationships in your current environment that still existed in the ancestral environment, such as friendships, alliances, and pair-bonding (“marriage”). But many of these situations and relationships today involve evolutionarily novel components (Facebook, written contracts enforceable by government, marriage certificates).
The key word in the Savanna Principle – The human brain has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment – is difficulty, not impossibility. It is sometimes possible to overcome the limitations of the human brain consciously – it is possible for us to remember that the characters we see on TV are professional actors who are paid millions of dollars to play scripted roles – but it is often difficult. Even when we are aware of something at the conscious level, we still act as if we weren’t, as when we become more satisfied with our friendships when we watch more TV. The observation captured in the Savanna Principle has very powerful and profound implications for evolutionary psychology and how the human brain functions.
https://www.psychologytoday.com/us/blog/the-scientific-fundamentalist/201002/the-savanna-principle
The Savanna Principle: Why Our Brains Are Stuck in the Stone Age
...there is nothing special about the human brain as a body part-leads to an important implication. Just as the basic shape and functions of the hand or the pancreas have not changed since the end of the Pleistocene Epoch ("the Ice Age") about ten thousand years ago, the basic functioning of the brain has not changed very much in the last ten thousand years. The human body (including the brain) evolved over millions of years in the African savanna and elsewhere on earth where humans lived during most of this time. This ancestral environment, where humans lived in small bands of 150 or so related individuals as hunter-gatherers, is called the environment of evolutionary adaptedness, or the ancestral environment. It is to the ancestral environment that our body (including the brain) is adapted. Even though we live in the twenty-first century, we have a Stone Age brain (just like we have Stone Age hands and a Stone Age pancreas).
The evolved psychological mechanism produces adaptive behavior in the ancestral environment. Adaptive behavior is behavior that increases the chances of survival or reproductive success by solving the adaptive problems. Eating lots of sweet and fatty foods, which contain higher calories, is adaptive behavior that solves the adaptive problem of procuring sufficient food to survive. Becoming jealous at the remotest possibility of a mate's sexual infidelity, and guarding that mate so that she could not have sexual contact with other men, is adaptive behavior that solves men's adaptive problem of paternity uncertainty.
Our hominid ancestors spent 99.9 percent of their evolutionary history as hunter-gatherers on the African savanna and elsewhere on earth. It was not until about ten thousand years ago, when the Agricultural Revolution happened, that our ancestors started planting and cultivating their food through agriculture and animal husbandry. Almost everything we see around us today-cities, nation-states, houses, roads, governments, writing, contraception, TVs, telephones, and computers-came about in the last ten thousand years. Recall that our entire body is adapted to the ancestral environment and that we have a Stone Age body (including the brain). That means that our body is not necessarily adapted for things that came about since the end of the Pleistocene Epoch about ten thousand years ago. Ten thousand years is a very short period of time on the evolutionary time scale; it is simply not enough time for our body to make changes to accommodate things that came about in the meantime, especially since the environment has been changing too rapidly relative to how slowly we mature and reproduce. (It takes humans about twenty years to mature and be ready to reproduce. And, remember, only twenty years ago, for most people outside of the military and scientific circles, there was no such thing as the Internet or cell phones.) In other words, we still have the same evolved psychological mechanisms that our ancestors possessed more than ten thousand years ago.
This observation leads to a new proposition in evolutionary psychology called the Savanna Principle, which states that the human brain has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment.
One example of an entity that did not exist in the ancestral environment is TV or any other realistic images of other humans, such as photographs, videos, or films. The Savanna Principle would therefore predict that the human brain has difficulty comprehending and dealing with images shown on TV. This indeed appears to be the case.28 A recent study shows that individuals who watch certain types of TV programs are more satisfied with their friendships, as if they had more friends or socialized with them more frequently. According to the Savanna Principle, this is probably because the human brain, adapted to the ancestral environment, has difficulty distinguishing between our real friends in the flesh and the characters we repeatedly see on TV. In the ancestral environment, any realistic images of other humans were other humans, and if you saw them repeatedly and they did not try to kill or harm you in any way, then more than likely they were your friends. Our Stone Age brain therefore assumes that the characters we repeatedly encounter on TV, very few of whom try to kill or harm us, are our real friends, and our satisfaction with friendships thereby increases by seeing them more frequently.
Maladaptive Adaptations
Take the example of our preference for sweets and fats as an evolved psychological mechanism. This psychological mechanism solved the adaptive problem of survival in the ancestral environment by allowing those who possessed it to live longer. Our preferred consumption of sweets and fats was therefore adaptive in the ancestral environment. However, we now live in an environment where sweets and fats are abundantly available in every checkout line in every supermarket, in every city, in every industrial society, twenty-four hours a day, seven days a week. In other words, the original adaptive problem (malnutrition) no longer exists; very few people die of malnutrition in industrial societies. Yet we still possess the same psychological mechanism that compels us to consume sweets and fats. Because our environment is so vastly different from the ancestral environment, we now face a curious situation where those who behave according to the dictates of the evolved psychological mechanism are worse offin terms of survival. Obesity (to which overcon-sumption of sweets and fats leads) hinders survival. The Savanna Principle suggests that we continue to have (currently maladaptive) preferences for sweets and fats, and as a result become obese, because our brain cannot readily comprehend the supermarkets, the abundance of food in general, and indeed agriculture, none of which existed in the ancestral environment. Our brain still assumes we are hunter-gatherers with very precarious and unpredictable sources of food. If our brain truly comprehended supermarkets, we would not crave sweet and fatty foods.
Similarly, male sexual jealousy is another evolved psychological mechanism that hasn't quite caught up to modern times. It solved the adaptive problem of reproduction in the ancestral environment by allowing men who possessed it to maximize paternity certainty and minimize the possibility of cuckoldry. Sexual jealousy was therefore adaptive in the ancestral environment. However, sex and reproduction are often separated in the modern environment; many episodes of sex do not lead to reproduction. There is an abundance of reliable methods of birth control in industrial societies, and many women use the contraceptive pill. For these women, sexual infidelity does not lead to childbirth, and their mates will not have to waste their resources on someone else's children. Even if their mates cheated on them and got pregnant as a result, reliable paternity testing removes any paternity uncertainty. In other words, the original adaptive-problem (paternity uncertainty) is less of a threat to reproductive success; men today are much less likely to invest unwittingly in someone else's genetic children. Yet men still possess the same psychological mechanism that makes them jealous at the possibility of their mates' sexual infidelity and compels them to guard their mates to minimize the possibility of cuckoldry. The fact that his adulterous wife was on the Pill at the time of her sexual infidelity offers very little consolation to a man.
Further, once again because our current environment is so vastly different from the ancestral environment, we now face a curious situation where those who behave according to the dictates of the evolved psychological mechanism are often worse off in terms of reproductive success. Extreme forms of mate guarding, such as violence against mates or romantic rivals, are crimes in most industrial nations. Incarceration, and consequent physical separation from their mates, does everything to reduce the reproductive success of the men. Yet men continue to exhibit sexual jealousy, and many men engage in extreme forms of mate guarding and vigilance, including violence.29 The Savanna Principle suggests that this is because their brains cannot truly comprehend effective birth control, written laws, the police, and the courts. If they did, they would not engage in extreme forms of mate guarding (such as violence) or any other criminal behavior for which they would likely go to jail.
We caution you that the Savanna Principle as stated above was proposed very recently (even though it is based on observations made earlier by pioneers of evolutionary psychology)30 and is not yet part of the established literature of evolutionary psychology. Its implications have yet to be subjected to rigorous experimental testing. However, we refer to it throughout the rest of the book, because we believe there is a kernel of truth to it and that it can explain a wide range of otherwise puzzling instances of human behavior.
Human Evolution Pretty Much Stopped about Ten Thousand Years Ago
The Savanna Principle points to a couple of very important-but often neglected-observations about human evolution: Evolution happens very gradually, and natural selection requires a stable, unchanging environment to which it can respond.
Evolution takes many generations, and so the speed of evolution of a species is relative to how long it takes for individuals of the species to mature sexually. Evolution happens faster for fast-maturing species and slower for slow-maturing species. Fruit flies are one of the fastest-maturing species in nature, and humans are one of the slowest. It takes only seven days for fruit flies to mature sexually under ideal conditions, whereas it takes fifteen to twenty years for humans. It means that there can be more than fifty generations of fruit flies in one year, before a human baby can even begin to walk. There are more than a thousand generations of fruit flies in one human generation (twenty years), for which humans need more than twenty thousand years. Evolution for fruit flies can happen pretty fast, which is precisely the reason why they are the favorite species for geneticists to study. Human evolution happens much, much more slowly. No human scientists can see it in action the way they can observe fruit fly evolution unfold in the lab.
The second point is even more important: Natural selection under most circumstances requires a stable, unchanging environment for many, many generations. For example, if the climate is very cold for centuries and millennia, then gradually individuals who have better resistance to cold will be favored by natural selection, and their neighbors who have less resistance to cold (who are more adapted to hot climates) will die out before they can leave many children. This will happen generation after generation, until one day all humans have great resistance to cold. A new trait-resistance to cold-has now evolved and become part of universal human nature. But this trait could not have evolved if the climate was cold for one century (only five human generations, albeit 5,200 fruit fly generations) and then hot for another century, only to be cold again in the third century. Natural selection would not know who (with which traits) to select.
Since the advent of agriculture about ten thousand years ago and the birth of human civilization which followed, humans have not had a stable environment against which natural selection can operate. For example, a mere two centuries (ten generations) ago, the United States and the rest of the Western world were largely agrarian; most people were farmers. In the agrarian society, men achieved higher status by being the best farmers; those who possessed certain traits that made them good farmers had higher status and thus greater reproductive success than others who didn't possess such traits.
Then, only a century later, the United States and Europe were predominantly industrial societies; most men made their living working for factories. Traits that make men good factory workers (or, better yet, factory owners] may or may not be the same as the traits that make them good farmers. Certain traits-such as intelligence, diligence, and sociability-probably remain important,31 but others-such as a feel for nature, the soil, and animals, and the ability to work outdoors or forecast weather-cease to be important, and other traits-such as punctuality, the ability to follow instructions, a feel for machinery or mechanical aptitude, and the ability to work jWoow-suddenly become important.
Now we are in a post-industrial society, where most people work neither as farmers nor factory workers but in the service industry. Computers and other electronic devices become important, and an entirely new set of traits is necessary to be successful. Bill Gates and Sir Richard Branson (and other successful men of today) may not have made particularly successful farmers or factory workers. All of these dramatic changes happened within ten generations, and there is no telling what the next century will bring and what traits will be necessary to be successful in the twenty-second century. We live in an unstable, ever-changing environment, and have done so for about ten thousand years.
For hundreds of thousands of years before that, our ancestors lived as hunter-gatherers on the African savanna, in a stable, unchanging environment to which natural selection could respond. That is why all humans today have traits that would have made them good hunter-gatherers in Africa-men's great spatiovisual skills, which allowed them to follow animals on a hunting trip for days and for miles without a map or a global satellite positioning device and return home safely; and women's great object location memory, which allowed them to remember where fruit trees and bushes were and return there every season to harvest, once again without maps or permanent landmarks.
For the last ten thousand years or so, however, our environment has been changing too rapidly for evolution to catch up. Evolution cannot work against moving targets. That's why humans have not evolved in any predictable direction since about ten thousand years ago. We hasten to add that certain features of our environment have remained the same-we have always had to get along with other humans, and we have always had to find and keep our mates-so certain traits, like sociability or physical attractiveness, have always been favored by natural and sexual selection. But other features of j our environment have changed too rapidly relative to our generation time, in a relatively random fashion-who could have predicted computers and the Internet a century ago?-so we have not been able to adapt and evolve against the constantly moving target of the environment.
Why Beautiful People Have More Daughters - From Dating, Shopping, and Praying to Going to War and Becoming a Billionaire-Two Evolutionary Psychologists Explain Why We Do What We Do.
...the majority of Homo sapiens’ existence took place in the Pleistocene (approximately 2 million to 10,000 years BCE), and so this epoch presented the greatest adaptive challenges to the species’ survival and reproduction. These were the contexts that shaped modern human physiology and sociality through natural selection. Large-scale civilizations, they argue, no longer resemble this so-called “environment of evolutionary adaptedness,” even though the humans that inhabit them retain the genetic and psychological makeup of their Pleistocene precursors. Many contemporary problems of Western social life, the story goes, can thus be attributed to this mismatch between the evolved human-animal and the novel problems of the present. As evolutionary psychologists John Tooby and Leda Cosmides are frequently quoted, “our modern skulls house a stone age mind” (Shenkman 2017: xv)...
...In my research, I investigate the rhetorical situations constructed by authors of mismatch arguments, looking at the ways that authors frame particular exigencies, the constraints that shape their arguments, and the audiences to whom these arguments are made (Bitzer 1968)...
...these arguments compose a movement in popular evolutionary science with numerous branches: Paleo diet enthusiasts focus on obesity, hypertension, physical inactivity, and food addictions. Theorists in Darwinian medicine draw attention to chronic disease, hygiene, and antibiotics. Ancestral fitness advocates focus on exercise, strength training, and the alienation of cosmopolitan life from the natural world. So-called Darwinian psychiatry similarly attempts to treat the effects of depression and anxiety as mismatches between ancestral and contemporary life. Still other authors examine issues such as pornography addiction, poor body image, and even poor political leadership and voter apathy...
http://blog.castac.org/2018/07/evolutionary-mismatch/
...Perhaps the most basic and well-documented mismatch in modern humans pertains to diet. Our ancestors in the African savanna often ran into drought and famine, but they also rarely had access to foods that were high in sugar and fat. Across evolutionary time, our ancestors evolved taste preferences such that they would prefer and, thus, seek out foods high in sugar and fat content—precisely because such foods were rare and adaptive under those ancestral conditions. Well, look at us now. We now have highly-processed foods that are full of sugar and fat and these foods are, ironically, incredibly cheap and easy to access. What a mismatch! And if you are looking for the cause of modern obesity problems (and resultant health issues such as Type-II diabetes) that characterize so many western nations, look no further. This evolutionary mismatch is the ultimate cause of all of these problems (see Wolf, 2010)...
The 7 Top Evolutionary Mismatches:
What is an evolutionary mismatch? –It is when some (biological) trait or adaptation acquired by the human body has become problematic given the culture or environment of modern society.
Let’s take a look at seven of the worst evolutionary mismatches in modern society by contrasting how things: 1-Used to be in the past, 2-What the situation is like now and 3-And what you can do to counteract this mismatch.
https://www.startgainingmomentum.com/7-evolutionary-mismatches-you-must-overcome/
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. 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.
https://www.psychologytoday.com/us/blog/naturally-selected/201804/evolutionary-mismatch
Human psychological mechanisms are adaptations that evolved to process environmental inputs, turning them into behavioral outputs that, on average, increase survival or reproductive prospects. Modern contexts, however, differ vastly from the environments that existed as human psychological mechanisms evolved. Many inputs now differ in quantity and intensity or no longer have the same fitness associations, thereby leading many mechanisms to produce maladaptive output. We present the precepts of this evolutionary mismatch process, highlight areas of mismatch, and consider implications for psychological science and policy.
Evolutionary mismatch, also known as mismatch theory or evolutionary trap, is a concept in evolutionary biology that refers to evolved traits that were once advantageous but became maladaptive due to changes in the environment.
https://tothemax.blog/2018/02/08/biggestproblem/
...Indeed, the vast majority of what ails us today — from leading killers like heart disease and cancer, to smaller health woes such as back pain — is the result of a mismatch between the environments we evolved in and the ones we now inhabit, argues Harvard evolutionary biologist Dan Lieberman in his sweeping new book, “The Story of the Human Body: Evolution, Health, And Disease.”...
Human psychological mechanisms are adaptations that evolved to process environmental inputs, turning them into behavioral outputs that, on average, increase survival or reproductive prospects. Modern contexts, however, differ vastly from the environments that existed as human psychological mechanisms evolved. Many inputs now differ in quantity and intensity or no longer have the same fitness associations, thereby leading many mechanisms to produce maladaptive output. We present the precepts of this evolutionary mismatch process, highlight areas of mismatch, and consider implications for psychological science and policy.
One area that remains relatively unexplored, however, is the impact of evolution and development on human health. In Mismatch: Why Our World No Longer Fits Our Bodies, Peter Gluckman and Mark Hanson grapple with this idea to provide an ‘evo–devo' model of many of the problems currently stalking the populations of the developed and developing worlds.
In this Spotlight, we ask whether modern humans are still evolving or whether we have stepped out of the path of natural selection.
Does Charles Darwin’s theory of evolution still apply to modern humans? Charles Darwin published his totemic work on evolution — On the Origin of Species — in 1859.
Based on the concept of natural selection, Darwin’s book provided scientists with a new toolkit for understanding the place that humans and animals occupy in the natural world.
The tome also gave clues as to where their earthly origins may lie.
According to Darwin’s thesis, evolution is slow and incremental with tiny genetic changes spread tens of thousands of years apart gently pushing forward changes in species.
In 2000, the paleontologist Stephen Jay Gould famously declared that “there’s been no biological change in humans in 40,000 or 50,000 years,” suggesting that evolution in humans is imperceptibly slow or has perhaps stopped altogether.
The British naturalist and broadcaster Sir David Attenborough concurred, even arguing that birth control and abortion have contributed to a halt in physical evolution among humans.
“We stopped natural selection as soon as we started being able to rear 90–95 percent of our babies that are born. We are the only species to have put a halt to natural selection, of its own free will, as it were,” he told the British magazine The Radio Times in 2013, adding that our species has instead ensured our continued survival through accelerating cultural evolution:
“Stopping natural selection is not as important, or depressing, as it might sound — because our evolution is now cultural […] We can inherit a knowledge of computers or television, electronics, airplanes, and so on.”
Natural selection requires variation
Both positions have been hotly contested. For instance, Dr. Ian Rickard — from Durham University in the United Kingdom — responded to Attenborough’s claims by pointing out that while abortion and birth control may mean that some people are having children while others are not, natural selection does not end here.
Rather, it places a renewed focus on the genetic material that is being passed along by those who are having children. Writing in The Guardian, Dr. Rickard explains, “Natural selection requires variation. It needs some individuals to thrive more than others.”
“So the improved survival prospects around the world over recent decades and centuries drastically decreases the potential for natural selection to work in those populations. But that is not the end of the argument. Even if everyone survives to the same age, there is still variation for natural selection to work with. Natural selection doesn’t really care about survival.”
And, a 2010 paper by Alan R. Templeton preemptively discarded Attenborough’s theory that physical evolution has been replaced by cultural evolution, arguing instead that “all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans.”
Templeton gives the example of how technological advances in transportation have facilitated a rapid mixing of the human gene pool across the globe, resulting in the waning of differences between different populations with overall beneficial effects to human health.
Human evolution is now ‘100 times faster’
In their 2009 book The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, Gregory Cochran and Henry Harpending calculate that — rather than there having been no biological change in humans over the past 50,000 years — human evolution has accelerated in the past 10,000 years.
Rather than slowing or stopping, the authors argue that evolution is now happening approximately “100 times faster than its long-term average over the 6 million years of our existence.”
Modern technology also presents us with opportunities to observe changes in humans at a molecular level. Scott Solomon, a biologist from the University of Texas in Austin, highlights in his book Future Humans: Inside the Science of Our Continuing Evolution that since 2000 — when Gould declared human evolution to have slowed or stopped — it has been possible to sequence the human genome.
In the 18 years since then, it has become much faster and cheaper to do so, providing scientists with an unprecedented insight into our recent evolutionary past.
From these data, Solomon explains, researchers have found evidence of natural selection altering genes responsible for our:
The Milk Revolution
One easy-to-understand example of how humans have evolved over recent centuries is how, on some continents, our bodies have adapted to tolerate the most abundant food sources common to that region.
Virus spread and climate change: A West Nile virus case study COVID-19 has made the entire world painfully aware of the terrible power that viruses can wield. Learn how climate change impacts the spread of other viruses, such as West Nile virus, in our feature article.
Around 11,000 years ago, for instance, adult humans were unable to digest lactose — the sugar in milk.
As humans in some regions began to rely on dairy farming as a source of nourishment, our bodies adjusted over time to be more able to digest this food, which, previously, was only tolerated by infants and toddlers.
We can see evidence of this evolution today because humans in areas with a long tradition of dairy farming — such as Europe — are much more tolerant of lactose in their diet than people in regions that do not have a heritage of dairy farming — such as Asia. Around 5 percent of people descended from Northern Europeans are lactose intolerant, compared with more than 90 percent of people of East Asian descent.
The Framingham Heart Study
One easy-to-understand example of how humans have evolved over recent centuries is how, on some continents, our bodies have adapted to tolerate the most abundant food sources common to that region.
Around 11,000 years ago, for instance, adult humans were unable to digest lactose — the sugar in milk.
As humans in some regions began to rely on dairy farming as a source of nourishment, our bodies adjusted over time to be more able to digest this food, which, previously, was only tolerated by infants and toddlers.
We can see evidence of this evolution today because humans in areas with a long tradition of dairy farming — such as Europe — are much more tolerant of lactose in their diet than people in regions that do not have a heritage of dairy farming — such as Asia. Around 5 percent of people descended from Northern Europeans are lactose intolerant, compared with more than 90 percent of people of East Asian descent.
“We see rapid evolution when there’s rapid environmental change, and the biggest part of our environment is culture, and culture is exploding,” Dr. Pardis Sabeti, a geneticist at Harvard University in Cambridge, MA, told the BBC.
“That’s […] the take-home message of the Framingham study, that we are continuing to evolve, that biology is going to change with the culture, and it’s just a matter of not being able to see it because we’re stuck right in the middle of the process right now.”
-Dr. Pardis Sabeti
Why are the Dutch so tall?
A 2015 study published in Proceedings of The Royal Society B asked the question, “Does natural selection favor taller stature among the tallest people on Earth?” The researchers behind the study tested this by looking at the tallest people on Earth: the Dutch.
But the Dutch were not always the tallest people on Earth. The researchers observe that in the mid-18th century, the average height of Dutch soldiers was 165 centimeters, which was well below the average of soldiers from other European countries and tiny compared with American soldiers, who were 5–8 centimeters taller than the average Dutch soldier.
But Dutch men have experienced a relatively sudden growth spurt, adding an extra 20 centimeters to their average height over the past 150 years.
During the same period, American men have only added 6 centimeters to their average height, and men from other European countries have struggled to keep pace with their neighbors from the Netherlands.
But why? The authors took into account disparities between the Netherlands and the United States in diet, social inequality, and the availability and quality of healthcare, but they concluded that it was natural selection that was driving up the height of the Dutch.
Put simply, Dutch women were more likely to find tall men attractive and were therefore more likely to have children with them. Tall Dutch men, the study confirmed, have more children than shorter Dutch men.
And, although the study found that tall Dutch women were less likely to have children than middling-height Dutch women, the tall women who did have children had more children than their shorter countryfolk.
In combination, these preferences exert a powerful natural selection effect on the average height of people in the Netherlands.
While this might not exactly be Marvel Cinematic Universe levels of genetic mutation — we are sad to report that we did not find any studies suggesting that the human race is about to acquire a telepathy gene — these examples illustrate how evolution works in terms of modern humans.
Evolution is persistent, everywhere, pushing our species forward in tiny increments. It might even be occurring with an accelerated regularity.
Adaptively Relevant Environment (ARE). The expression ‘‘relevant environment’’ may also serve as a shorter label. The key idea motivating the ARE concept is that an organism consist of a large number of special-purpose adaptations, each interacting with only a part of the organism’s environment. Thus, when a particular element of an environment changes, it is likely to affect some adaptations but not others. Logically, this idea is closely related to the idea that evolutionary change is mosaic: In the course of evolutionary change, some aspects of organisms change while others remain the same. In order to understand an adaptation fully at the proximate level, we need to study its design, the structure of its relevant environment, and the interaction of the two.
The EEA concept was introduced by John Bowlby in his classic 1969 and 1973 studies of attachment and loss in human infants and children. Bowlby defined a species EEA as “…the environment in which a species lived while its existing characteristics, including behavioral systems, were being evolved, and . . . the only environment in which there can be any assurance that activation of a system will be likely to result in the achievement of its biological function . . .’’ (p. 82).
He identified the human EEA as “…the one that man inhabited for two million years until changes of the past few thousand years led to the extraordinary variety of habitats he occupies today.’’(p. 59).
Bowlby defined adaptedness as contributing to the survival of the species or populations. However, current evolutionary psychologists now define it, in line with contemporary theory, as serving the inclusive fitness of individuals. Aside from this, they have not modified the concept greatly. Barkow, Cosmides, and Tooby review the basics of this concept in the introduction to The Adapted Mind, an edited volume designed to present and explain the newly developing field of evolutionary psychology to a wider audience. They summarize the EEA assumptions as follows: “…evolved structure of the human mind is adapted to the way of life of Pleistocene hunter-gatherers, and not necessarily to our modern circumstances…” The few thousand years since the scattered appearance of agriculture is only a small stretch in evolutionary terms, less than 1% of the two million years our ancestors spent as Pleistocene hunter-gatherers’’(p. 5).
Media "Friends" (from No Sense of Place)
Electronic media's encroachment on place is suggested in one of the cliches of the broadcasting industry: "This show is brought to you live from . . ." Once, physical presence was necessary for the experience of a "live," ongoing event. You "had to be there" to experience an informal and intimate interaction. Place once defined a very special category of communication. Electronic media, however, have changed the relative significance of live and mediated encounters. Through electronic media of communication, social performers now "go" where they would not or could not travel, and audiences are now "present" at distant events.
What sort of relationship is formed between people who experience each other only through electronic media? In a perceptive article on media written in the 1950s, Donald Horton and R. Richard Wohl suggest that even when the communication is unidirectional, such as in radio and television, a special relationship develops that did not and could not exist in print media. What is unusual about the new mass media, they suggest, is that they offer the illusion of face-to-face interaction with performers and political figures. "The conditions of response to the performer are analogous to those in a primary group. The most remote and illustrious men are met as if they were in the circle of one's peers." 7
Horton and Wohl suggest that the new media lead to a new type of relationship which they call "para-social interaction." They argue that although the relationship is mediated, it psychologically resembles faceto-face interaction. Viewers come to feel they "know" the people they "meet" on television in the same way they know their friends and associates. In fact, many viewers begin to believe that they know and understand a performer better than all the other viewers do. Paradoxically, the para-social performer is able to establish "intimacy with millions."
Horton and Wohl's framework explains the popularity of talk show hosts such as Jack Paar, Johnny Carson, and Dick Cavett. These are people, according to Horton and Wohl, who have no traditional performance skill; they are not singers, musicians, actors, or even professional-quality comedians. The content of their "performance" is mostly small talk and running gags. Yet they are likeable and interesting in the same way that a close friend is likeable and interesting. The viewer can rely on them to be "themselves." As Horton and Wohl suggest, the pure para-social performer is simply "known for being known." Within this framework, it makes sense that stories about Johnny Carson's threats to resign from the "Tonight" show, his arrest for suspicion of drunk driving, and his divorce settlement have been reported on the network news and in front page headlines.
Even performers with traditional skills often exploit the intimacy of the new media (or find that they cannot avoid it). As a result of close personal observation, many athletes, musicians, journalists, and politicians are now judged not only on the basis of their "talent" but also on the basis of their personalities. The para-social framework may explain why many singing stars turn to more and more personal lyrics and themes as their careers develop and why public officials often add more private information to their public speeches as they become more widely known. The theory can also be extended to actors playing fictional roles. For many viewers, soap opera and other television characters are real people to whom they can turn for inspiration and advice. During his first five years on network television, the fictional "Dr. Marcus Welby" received a quarter of a million letters, most requesting medical advice. 8
Horton and Wohl do not link their framework to an analysis of the impact of electronic media on physical place, but they do offer observations that support such an analysis. They note, for example, that the parasocial relationship has its greatest impact on the "socially isolated, the socially inept, the aged and invalid, the timid and rejected." 9 Because electronic media provide the types of interaction and experience which were once restricted to intimate live encounters, it makes sense that they would have their greatest effect on those who are physically or psychologically removed from everyday social interaction. (One researcher has found that the strength of the para-social relationship increases with the viewer's age, that many elderly people think of newscasters as their friends, and that some older viewers "interact" with newscasters by responding to them verbally. 10 ) Even among "average" people, the parasocial relationship takes its place among daily live interactions with friends, family, and associates. Indeed, "real" friends often discuss the antics of their para-social friends.
The para-social framework is extremely useful in analyzing many phenomena not specifically discussed by Horton and Wohl. The framework explains, for example, why it is that when a "media friend" such as Elvis Presley, John Kennedy, or John Lennon dies or is killed, millions of people may experience a sense of loss as great as (and sometimes greater than) the feelings of loss accompanying the death of a relative or friend. Even an awareness of the para-social mechanism is not enough to permit escape from its "magic"; the death of John Lennon, for example, was strangely painful to me and my university colleagues who had "known" him and grown up "with" him. Sociologist Candice Leonard has suggested that such mediated relationships lead to a "new genre of human grief." 11
Unlike the loss of a real friend or relative, the death of a media friend does not provide traditional rituals or clear ways to comfort the bereaved. Indeed, the mourning for a para-social friend is filled with paradox and helplessness. Attempts to comfort the dead person's family with words or flowers are intrusions by strangers. And intensely felt personal grief is simultaneously strengthened and weakened by the extent to which it is shared with the crowd. In order to banish the demons of grief and helplessness, therefore, thousands of people take to the streets or hold vigils near the para-social friend's home or place of death.
Ironically, but appropriately, the media provide the most ritualized channels of mourning. Radio and television present specials and retrospectives. And many people use the telephone to contact real friends who shared the intimacy with the para-social friend. But the final irony is that, in some ways, the para-social performer does not die. For the only means through which most people came to know him or her—records, films, and videotape—are still available. The relationship is frozen, rather than destroyed. In part, it is the potential and hope for increased intimacy that dies, and the never to be face-to-face consummation of the relationship that is mourned.
The para-social relationship has also led to a new form of murder and a new type of murder motive. Police generally distinguish between two types of murders: those committed by a person who knows the victim, and those committed by a stranger. Yet, there is now a third category: the para-social murder. While the media and police noted that John Lennon's murderer was a "complete stranger"—meaning that the two had never physically met—they overlooked the powerful para-social ties between them. Mark David Chapman knew John Lennon so well that for a time he thought he was John Lennon. 12 A similarly bizarre relationship existed between would-be presidential assassin John Hinckley and actress Jodie Foster. Hinckley committed his "historic act" in order to cement a "personal" relationship with Foster. 13
In both love and hate, normal and bizarre, the para-social relationship is a new form of interaction. It has some of the traditional characteristics of both live encounters and communication through books, but it is, in fact, neither.
In formulating the notion of para-social interaction, Horton and Wohl point to the differences between "old" and "new" media. But they overlook the overall evolutionary trend, even within each type of medium, toward a shrinking of the differences between live and mediated encounters. Writing systems have evolved toward greater replication of spoken sounds (from hieroglyphs to the phonetic alphabet) and photography and electronic media have evolved toward fuller representations of face-to-face sensory experiences.
Media theorist Paul Levinson has detailed the long-term evolutionary course of media. 14 He argues that the trend is toward fuller replication of the means of communication that existed before media and technology. Levinson's theory gives substance to our intuitive sense that one form of a medium is "better" than another. The addition of voice to the telegraph, or sound to silent movies, or color to television, he suggests, is perceived as an "improvement" simply because the medium becomes less like a medium and more like life.
Levinson uses his theoretical framework to reject the criticism of many social theorists who suggest that media are distorting the human condition by taking us further and further away from "reality." Levinson argues, in contrast, that human beings use media to recreate as "natural" and as "human" a means of communicating as possible, while at the same time overcoming pre-technological limitations to communication (lack of permanent records, impossibility of speaking or seeing across vast distances, impossibility of being in two places at once, and so on).
Levinson's fascinating description of media history shows how an early form of a medium first gives up aspects of the "real world" in order to overcome a spatial or temporal limitation and how later forms of the medium then recapture aspects of natural communication. The telegraph, for example, gave up speech in order to travel quickly across the continent and globe; but then the telegraph evolved into the telephone which regained the human voice.
A major problem with Levinson's framework, however, is that he completely overlooks the ways in which the original spatial and temporal "limits" help to define the nature of social interaction. In suggesting that media recreate reality, Levinson defines "reality" in terms of sensory functions of communication —seeing, hearing, speaking. He ignores the ways in which the substance of human interaction changes when the barriers among situations are removed.
The theories of Levinson and of Horton and Wohl are helpful here because they suggest that face-to-face interaction is no longer the only determinant of personal and intimate interaction. The evolution of media has begun to cloud the differences between stranger and friend and to weaken the distinction between people who are "here" and people who are "somewhere else." These frameworks suggest that electronic media are unique in that they mask the differences between direct and indirect communication. What is missing from these theories, however, is an appreciation of how much social behavior changes when people are able to communicate "as if" they were in the same place when they are, in fact, in different places.
The Binding of Message to Context
The discussion thus far has suggested that electronic media weaken the significance of physical place as a determinant of social situations. Interestingly, many electronic media also strengthen one aspect of the relationship between messages and physical locations. For just as expressive and presentational messages are always about the emitting person, so are they tied to the physical location of the sender. Quotes in a newspaper may have nothing to do with the place in which the words were spoken, but a recording of a speech also captures aspects of the physical environment in which the speech was made...
Unsorted Entries —————————————-
Mismatch, Supernormal Stimulus, Evolutionary Psychiatry Medicine
One of the greatest gifts of the field of evolutionary psychology pertains to work on evolutionary mismatch in humans. By understanding how evolutionary mismatch connects with modern problems, the field can offer clear guidance for living. Following are five examples of evolutionary mismatch in modern humans, along with some clear guidance for dodging the evolutionary mismatch trap; Diet, Exercise, Politics, Extended Family & Education.
Evolutionary psychology is the theory that evolution plays a significant role in the way our brains are currently wired. For tens of thousands of years (99% of human existence), our environment was wild. We lived off the land, hunted, gathered and later farmed. As a result, we evolved to deal with an environment where food was scarce, threats were ever present and acceptance within the group, or tribe, was everything.
Within a relatively short space of time, though, huge changes occurred. The Agricultural Revolution brought us one step removed from the way we’d adapted to survive, but the Industrial Revolution and, now, the Information Age, has brought us light years from our ancestral origins.
In some ways, this is a problem. Evolution moves at a far slower pace than human innovation and, as a result, we find ourselves living in a world out of sync with how we’ve evolved to adapt.
Evolutionary psychology calls this an evolutionary mismatch and examples of this phenomenon are everywhere.
We crave fatty, and sweet, foods because we evolved to live in a world where food, and energy, supplies were scarce (a disaster for our health now that we live in a world – at least in the developed world – where there is an overabundance of food). We adapted to live in tribal communities (a clan could extend to 100 to 150 people) and, as a result, feel isolated and alienated by the smaller and smaller family, and individual, units where we now reside. Finally, for millennia, we inhabited the African savannah, with its open spaces and abundance of nature. As a result, we feel depressed by living in polluted and overpopulated cities, hemmed in to our office spaces (or, increasingly, our homes), rarely getting the time to venture outside.
Evolutionary psychology highlights a serious problem. We struggle to function in our present-day environment because our bodies and brains evolved for something else.
...The first great wave of mismatches was triggered by the origins of farming. As people transitioned from hunting and gathering to farming, they settled down in large, permanent communities with high population densities, not to mention lots of sewage, farm animals and various other sources of filth and contagion. Farmers also became dependent on a few cereal crops that yield more calories but less nutrition than what hunter-gatherers can obtain. The resulting mismatches included all sorts of nasty infectious diseases, more malnutrition, and a greater chance of famine. A second great wave of mismatch, still ongoing, occurred from the industrial and then post-industrial revolutions....
Abstract: Human psychological mechanisms are adaptations that evolved to process environmental inputs, turning them into behavioral outputs that, on average, increase survival or reproductive prospects. Modern contexts, however, differ vastly from the environments that existed as human psychological mechanisms evolved. Many inputs now differ in quantity and intensity or no longer have the same fitness associations, thereby leading many mechanisms to produce maladaptive output. We present the precepts of this evolutionary mismatch process, highlight areas of mismatch, and consider implications for psychological science and policy.
....... Supernormal Stimuli
....... Evolutionary Psychiatry
....... Evolutionary Medicine
