Why do we gorge on delicious food until we feel like we are going to explode? Why is the divorce rate in America so high? Why are we more afraid of snakes than cars? And what do these questions have in common?
The answer is very possibly inside our DNA.
Evolutionary psychologists study the answers to these questions by looking at the lives of our ancestors who roamed the planet thousands of years ago, theorizing that we have the minds of hunter-gatherers. Thinking about the process of evolution, this theory makes sense. We know evolution is slow, occurring over the course of many thousands of years and we know that we have spent 95% of our evolutionary history in a hunter-gatherer environment. Thus, looking at how humans operated many thousands of years ago as foragers, we may be able to answer questions about a driving force behind our actions in today’s world.
In the four areas of our lives listed below, research along with theory has linked questions about our modern-day-selves to answers provided by our foraging-ancestors.
1. Diet – Why do we tend to overeat? And why do we enjoy a wide variety of foods?
Our hunter-gatherer ancestors spent their days gathering fruits and vegetables or hunting down meat. Efforts to obtain food were not unchallenging, nor was food an over-abundance. Foods rich in carbohydrates or fats were rarely available, though when obtained they provided major advantages such as: (1) instant energy or (2) the ability to store food for longer periods of time. These days, we still crave carbohydrates and fats thanks to our ancestors, but food is no longer as scarce. Our hunter-gatherer era minds will tell us we need to chow down a whole cheesecake, as the mind doesn’t realize there are twenty other cheesecakes sitting in the grocery store freezer isle awaiting purchase.
2. Physical Activity – Are our sedentary lives hurting us more than we realize?
Our foraging ancestors depended on physical activity through the process of gathering fruits and nuts or running down a zebra for the tribe’s weekly protein. It is clear our foraging ancestors included significant energy exertion as part of their daily routines to the extent the brain would become adapted to this lifestyle. Looking to modern society, however, we often have to force ourselves just to stand up and move around, especially for those of us with a sedentary job (or those of us with an utmost love for video-games, social media, or the magic land of Wikipedia). Available research, as a result of modern science and technology, has shown physical activity to stimulate human brain connectivity where an activity, such as running, triggers activity in our brains related to multi-tasking, planning, inhibition, and attention. This activity shows the brain is still functioning at an optimal level when our bodies are physically active, as the bodies of our hunter-gatherer ancestors would have been.
3. Fear – Why are we afraid of snakes but not cars?
Snakes were a realistic fear for our foraging ancestors where a poisonous bite could mean the end of life as they knew it. Though poisonous snakes still exist in the modern world, the chances of an encounter with one of these species in an industrial city is slim to none. Yet, during a recent Gallup survey about “What scares America most?” snakes made the top of the list, with 56% of Americans fearing snakes. Meanwhile, the chance of dying in an automobile accident is about 1 in 103, and the fear of cars or car accidents didn’t even make the list. Our fears clearly aren’t in alignment with the threats of our modern world, and we have our ancestors to thank. Since cars didn’t exist thousands of year ago, we haven’t developed the proper fear when turning on the ignition, and we are left with irrational and mostly useless fears (other than for making interesting cinema or vacationing in the Amazon).
4. Socialization – Why do we feel so alone in a world in a world with so many people? And why do so many marriages fail?
Though the types of family units adopted by our ancestors is still debated (nuclear family versus polygamous groups), we do know their social lives were vibrant. Hunter-gather tribes were limited in size, with no greater than 150 people, which made getting to know other members of the group an easy task. These groups spent their days and nights with each other, where privacy was not a priority. The lives of our ancestors depended on the sharing of information such as where the best berries are found or who will lead the gazelle hunt, but also included the sharing of gossip such as who was sleeping with who, which elder told the best stories, or who was the worst man to father a child. The point is, our ancestors spent their lives in close contact with other humans, constantly sharing information and feelings with one another. Though we still interact with others, the size of our “tribe” has grown larger to fill cities and countries, while the number of people we spend significant time with has grown smaller. These changes lead to feelings of loneliness and isolation, and even could be the cause of failing marriages. Raising a child is not an easy task, as anyone with children knows, and we have pushed ourselves to raise children with much less social support than our ancestors. Our brains aren’t used to being without connection, and isolation can lead to feelings of loneliness, depression, and divorce as a result. Though the route to change our isolated ways of life may be complicated, it is important to know that these feelings are (at least in part) hardwired in our brains, and having other humans close by to count on is likely more beneficial and important than we realize (especially to those of us that are introverted or socially awkward by design).
As compared to our ancestors, we eat more and exercise less. We fear things that are of little threat yet aren’t scared of the things that are most likely to kill us. We hastily marry, when we know we have only half a chance of making it work. We spend our days in a world filled with billions of people, yet we feel alone.
All these contradictions seem to be answered by looking to a time thousands of years ago when our brains evolved. Though we can’t necessarily change our DNA (at least not yet), it seems an important task for us to learn more about the worlds of our foraging ancestors, and in turn learn more about ourselves. As hunter-gatherer societies moved around often, and lived before the time of written language, the resources and research we have regarding their ways of life are limited. However, one thing seems clear: the connection our ancestors had with the natural world. The extent of knowledge they needed to acquire about plant and animal life in order to survive as foragers is astronomical. And all this information was stored in a map of the natural world within their brains. Therefore, a link to the natural world is likely hardwired inside of us, and available for access, regardless of how much the modern world tells us to push it aside. It is very possible gaining access to the areas of our brains which are deeply connected to nature, as gifted to us by our ancestors, may guide us out of the feelings of loneliness and isolation, and comfort us with feelings of connected-ness and meaning.
 Sapiens by Yuval Noah Harari
 Carbohydrates and fats listed as 1 and 2 respectively