Rise of the mismatch diseases
According to evolutionary biologists and psychologists, many physical and mental ailments result from a lack of fit between the environment people evolved for and the one in which they now live — known as ‘mismatch diseases.’
Over millions of years, each species accumulates a large number of evolutionary adaptations to help it survive and, against all the odds, reproduce. Such features are passed down genetically through the generations — adapting the animal to the environment in which it lives.
Modern humans — homo sapiens — evolved 200 thousand years ago in the African savannah. Living in small groups, they were in effect, “on a camping trip that lasted a lifetime, and they had to solve many different kinds of problems well to survive and reproduce,” says Leda Cosmides and John Tooby, evolutionary psychologists from the University of California.
But, following tens of thousands of years of relative stability, the last few hundred generations have brought about cultural revolutions impacting the way humans live.
Agriculture began only 12,000 years ago. “Farming created more food and allowed populations to grow, but for most of the last few thousand years, the average farmer had to work much harder than any hunter-gatherer, experienced worse health, and was more likely to die young,” says Daniel Liebermann, Professor in the Department of Human Evolutionary Biology at Harvard University, in The Story of the Human Body.
The next cultural upheaval, the Industrial Revolution, began in the late 18th century. Rural societies were transformed into industrial, urban ones, with new working conditions profoundly impacting housing, sleeping, eating, and living conditions.
Most recently, and perhaps most far-reaching of all, the digital revolution began in the 1970s. The evolving use of new technology continues to dramatically change human communication, work, play, and politics.
“Cultural changes have altered the interaction between our genes and our environments in ways that contribute to a wide range of health problems,” says Lieberman.
Where are humans going wrong?
Our modern way of living has resulted in “widespread illnesses such as heart disease, certain cancers, osteoporosis, type 2 diabetes, and Alzheimer’s, as well as scores of other lesser ailments,” says Lieberman. It also, most likely, contributes to “a sizeable percentage of mental illnesses, such as anxiety and depressive disorders,” he continues.
Our habits are proving fatal.
The craving for calorie-dense food — previously an evolutionary advantage — along with reduced physical activity, has led to increases in diabetes, heart disease, and weight gain. Two-thirds of Americans are now overweight or obese, and the numbers are rising.
Human vision evolved for watching natural, moving stimuli, including trees, and animals. Days spent looking at close-up, static images — books, computer screens, and phones — has caused problems with eye development and maintenance. As a result, myopia (nearsightedness) is on the increase.
The drive to disinfect everything and a relatively recent — in human terms — concern with meticulous personal hygiene is linked to deficiencies in infants’ immune systems and the development of asthma and allergies.
But physical mismatches are only part of the story
Scientists recognize that many evolved brain processes are also no longer a good fit for the modern world. Changes in working, living conditions, recreation, and relationships result in ‘psychological mismatches.’
The “prehistoric brain was focused on allowing our ancestors to live and survive in small groups of families and friends, who moved around in a natural environment full of danger.” says Ronald Giphart and Mark van Vugt, in Mismatch: How Our Stone Age Brain Deceives Us Every Day.
Humans have therefore inherited behavior that focusses on short-term, local problems, such as food, shelter, and avoiding prey. While useful for immediate survival, this mindset is inadequate to tackle less pressing and less visible challenges: climate change, obesity, war, and the plight of refugees.
Technology has changed how humans see themselves and how they relate to others. Science has shown that even limited exposure to social media can impact stress levels, anxiety, self-confidence, and lower overall happiness. One study found that viewing just ten photos of attractive women weakened heterosexual males’ commitment to long-term partners. While other research found links between time spent online, a devalued body-image, and reduced levels of self-esteem.
In work, close-knit relationships and face-to-face human interactions are replaced by complex management structures. While human ancestors took decisions as a group — learning by mirroring the behavior of positive role models — modern workplaces encourage status and power differences. The resulting stress and anxiety can come at the cost of relationships, good parenting, a healthy immune system, and happiness.
Less time outside, inadequate physical activity, poor diets, and, most importantly, insufficient family support has also left recent mothers at an increased risk of postpartum depression.
So, if the way we live, is not in balance with who we have evolved to be, what do we do?
Well, the good news is, we don’t need to throw away all our modern conveniences.
“There is much to be said for a return to more of life’s simple pleasures, but a knee-jerk opposition to technology and progress is facile and futile,” says Lieberman.
Humans have a choice — it doesn’t have to be this way.
People can do nothing and hope something changes — that the human race evolves to better suit the environment or science finds a quick fix — or more sensibly alter the relationship between body, mind, and the environment.
Humanity must find a way to work with, or around, their small-scale, ancestral psychology — to look toward the broader view of humanity, and the environment, opting to consider the long term, not just the short term.
Physical and mental well-being is most likely when people maintain a balanced relationship with, rather than an over-reliance on, digital technology, and direct experience is favored over proxy.
Working environments must facilitate and encourage movement and socializing — providing employees with access to outdoor spaces, exercise, and appropriate breaks throughout the day.
Each change, even small ones, can make a difference. Ultimately, it is a choice, but history dictates that balance is usually the best.
Humanity can view these physical and mental warnings as a call to arms — a challenge for society to live in a manner that is in harmony with how human ancestors lived — or to ignore, and continue to live a mismatched life.
This post was originally published, along with others, on Medium