The Urbanization-Mental Health Connection

Three evolution-based reasons that humans were shaped for small-scale living

Posted Aug 28, 2016

Glenn Geher
Source: Glenn Geher

Every day I thank my lucky stars that I live in the small upstate town of New Paltz. Apple trees outnumber people in this place by about 1,000-to-1. When you go to the grocery store, you are guaranteed to know about ⅓ of the folks shopping there. My kids know just about every single kid in their grade.

And with small-town living come many perks. Just yesterday, we held the annual SOS4Kids triathlon that my son completed. About 60 kids in the town completed this little race - and it was a typical New Paltz event where everyone knew everyone else who was there. All the grownups cheered for all the kids. All the kids cheered for all the other kids. And the 60 brave little finishers now have another piece of life experience from this rinky dink town that will help them carve out their futures. This is New Paltz, New York. And this is how we roll.

I guess it’s not for everyone, but you could not pay me enough money to leave this place.

As an evolutionary psychologist, I’m always interested in the evolutionary origins of things (see my brief book, Evolutionary Psychology 101, for a summary of this field). Here, I ask this: Are there reasons that are rooted in evolutionary psychology that can help us understand why small-town living seems to be so healthy?

To address this issue, I started looking at the flip side of this question: Is there something inherently unhealthy about large-scale living? Below, complete with evolutionary analyses, are three research-based points that can help us understand why small-town living is, in some objective kind of sense, so wonderful for development and for building social communities.

1. Dunbar’s Number.

In a highly cited piece of academic scholarship, Robin Dunbar, a cognitive psychologist at Oxford, provided a powerful explanation for understanding human social cognitive processes. In social processing, we have a limit to the number of people we can comfortably think about. And that limit seems to be about 150. This number tends to correspond to the typical size of a nomadic community any place around the world. And the size of nomadic communities, from an evolutionary perspective, is important - because up until about 10,000 years ago, when agriculture took hold, all of our ancestors, during the lion’s share of human evolution, lived in small nomadic groups. Implication: Our minds were designed for small-scale living.

2. Psychological health is, on average, worse in cities than in rural areas.

All kinds of mental disorders have higher prevalence rates in cities (see: Srivastava, 2009). This includes major mental disorders (e.g., schizophrenia), emotional disorders (e.g., major depression), cognitive-developmental disorders (e.g., dementia), and more. From an evolutionary perspective, this fact is not surprising. Large cities provide a classic evolutionary mismatch - if our ancestors were shaped by nature to interact with 150 people at most, living in a city of 8,000,000 or so is deeply out of synch with our nature.

3. The link between psychological health and urbanization is found across the globe.

Scholars who have examined how general this trend for mental health and urbanization to be linked is have found it to be pretty much the case across the globe (see Trivedi et al., 2008). Across multiple continents, urbanization has been linked to relative increases in mental health problems. Of course, from an evolutionary perspective, the universality of such a relationship provides insights into the evolutionary origins of this issue.

Summary

The human mind was sculpted by evolutionary forces under pre-agrarian conditions for the lion’s share of human evolution. To a large extent, as a result, our minds evolved for small-scale living. Modern urbanized contexts, then, mismatch our natural psychological and social environments in important ways. The relatively high prevalence of mental disorders in urbanized areas that is found across the globe, thus, may well be understood in terms of the evolutionary-mismatch position proposed here.

Bottom Line

I love living in a small town. In my town, everyone just about knows everyone else. People support and look out for each other - and we support each others’ kids. Whether it’s the annual apple festival, the annual Italian festival at the church, free movie night down at Water Street Market, the championships for the kids’ swimming league, playoff games for the local little league, regional kids' soccer tournaments, or just walking into the grocery store to bump into old friends, small-town living has perks. And evolutionary psychology can help us understand why.

I’d write more, but we’ve got plans to go to the county fair with some friends ...

References

Dunbar, R. I. M. (1992). Neocortex size as a constraint on group size in primates. Journal of Human Evolution, 22(6), 469–493.

Geher, G. (2014). Evolutionary Psychology 101. New York: Springer.

Srivastava, K. (2009). Urbanization and mental health, Industrial Psychiatry Journal, 18, 75-76.

Trivedi Jitendra, Sareen Himanshu, Dhyani Dhyani, Mohan Mohan. Rapid urbanization - Its impact on mental health. A South Asian region perspective Indian Journal of Psychiatry. 2008

UN, World Urbanization Prospects The 2007 Revision; and Mark R. Montgomery, “The Urban Transformation of the Developing World,” Science. 2008;319(5864):761–64.