William C. Sanderson Ph.D.

Our Evolutionary Selves

We Live in a Zoo!

How our unnatural living environment creates all types of problems.

Posted Jun 26, 2017

Humans live in a zoo.  Well, most of them anyway, the exception being those who continue to live in hunter-gatherer societies.  Picture an animal in a zoo.  Whether it be in a cage or some type of artificial habitat it is not living in the environment that its unique nature was adapted for.  Would you expect this animal to display optimal physical, behavioral, and emotional functioning?  No!  It may live longer because it is not faced with challenges posed by predators and finding food.  But it is not living to satisfy its true nature -- that what is designed for.  So it seems perfectly reasonable to assume the same is true for humans if we live in a zoo as well?   We’re safer and we live longer than those who lived in the evolutionary environment.  But emotionally, and physically, we may be worse off. Read on...

Several years ago, after a snowstorm, I was throwing potato chips outside for the squirrels.  As I was doing so my wife stated “Don’t throw those outside -- the squirrels will get sick!”  I agreed with what she said and stopped doing so.  And then it struck me -- how could this food be acceptable for me to eat but not for the squirrels!? After all, this was in my food cabinet.  Why was it so obvious to me that squirrels should be eating “ecologically relevant” foods (that is, those things they consumed throughout their evolutionary history and can acquire in their natural environment) -- but I do not have the same expectation for humans!  The fact is much of the food that is consumed by humans are far from ecologically valid foods.  And therefore it is no surprise that many problems and illnesses that humans face are a function of our diet that is incompatible with our evolutionary history (e.g., processed sugar, excessive salt, unnatural fats, etc.)

This reflects the essence of what I believe is perhaps the most important and practical consideration of evolutionary theory -- not just for our physical health -- but for our psychological health as well: the mismatch between the environment humans evolved in (i.e., the ancestral environment) and the one we currently exist in.  In fact, the environment we have evolved in (quite different than the one we are living in) is the one that our brain is best prepared to function in.  For 99.9% of human’s evolutionary history, we lived as hunter-gatherers in small groups of people (similar to some societies that exist today), concerned predominantly with issues related to our survival (e.g., finding food, avoiding predators and contaminants).  That’s what our brain is built for.  And being involved in day to day survival is certainly a meaningful activity (our evolutionary ancestors were not reading self-help books on how to find meaning in life).

Photo by Patrice Letarnec, used with permission
Source: Photo by Patrice Letarnec, used with permission

So that is where my “we live in a zoo” metaphor comes from.  Consider a tiger plucked from its natural environment -- (the one similar to its ancestors evolutionary history) and placed in a zoo.  While there may be some resemblance of the two environments, the size (significantly smaller), food sources (given food rather than hunting), socialization (perhaps living in greater proximity with other tigers with the zoo environment), ability to mate, etc., are likely to impact the tiger’s behavior and emotional state.  Ditto for humans.

Perhaps one of the most important contributions of evolutionary theory is examining how particular evolved psychological adaptations (EPA - see my previous column for an explanation of this concept) interact with an unprecedented rapidly changing environment.  Specifically, the current context in which we all function in is far from that which our mind was originally conceived for  (contrast living in a city/suburbs and the impact of technological advances, etc. versus a hunter-gatherer lifestyle).  This idea is known as mismatch theory which is a powerful framework that has significant implications for the rise in human suffering and psychopathology -- not to mention the increased prevalence of physical illnesses such as metabolic disorders, obesity, heart disease -- that we are observing in the present environment.  Indeed, despite all of our attempts and billions of dollars spent to decrease emotional

disorders and increase the population’s well-being in general every indicator suggests these problems (i.e., mental illness, general distress and dissatisfaction) are increasing -- see this article from the former Director of the National Institute of Mental Health!  

Thus the need to consider a reset.  And that is where the implications of evolutionary theory and in particular mismatch theory comes into play.  In future columns I will contemplate the implications of the rapid increase in technology -- especially the computer/internet and all of the associated features such as social media, constant access to information, videos, etc. --and how these influence the prehistoric brain and in particular our cognitive and emotion systems -- and our overall emotional functioning.  I will also discuss the ease of using extreme violence that is brought to us by technology (guns, conventional and nuclear bombs, drones) -- for which the human brain is clearly unprepared to manage without potential disastrous consequences.