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*This piece was originally published on June 12, 2019*

Experiences of mental illness are common in the United States and behind each individual case is a history. In his book, Good Reasons for Bad Feelings: Insights from the Frontier of Evolutionary Psychiatry, Randolph Nesse, the director of the Center for Evolution and Medicine at Arizona State University, looks at emotional and mental disorders from an evolutionary perspective, and considers why natural selection left us with fragile minds. 

Three Takeaways:

• Nesse says our bodies and minds are vulnerable for two reasons. First, we don’t live in the environment in which we evolved, but a modern one that conflicts with our ancient past. Second, our bodies and minds were not shaped for many of the things we want to pursue in modern day life, including happiness, health, and longevity. 
• According to Nesse, a lot of the “bad feelings” that bother us — anxiety, jealousy, and low mood — are symptoms of malfunctioning mechanisms shaped by natural selection. Some of our bad feelings can be useful, he argues, but only when they “go off” in the right circumstances, to warn us of possible danger or that something might be wrong. 
• There are common evolutionary reasons for people’s experiences of mental illnesses, but each situation is different. Nesse says that there is no one-size-fits all solution. From medication to behavioral therapy, one patient might find the perfect treatment plan that wouldn’t even begin to help the next.

More Reading:

• How much do we suffer because of that mismatch between the ancient world in which our brains evolved, and our “modern environments”? Psychology Today explores the relationship between our brains and the world around us. 
• While many label “anxiety” or “fear” as bad feelings, some may enjoy the experience of such emotions. The Atlantic interviews Dr. Margee Kerr to talk about the nature of fear and why some of us seek it out. 
• Science Daily describes a study of over 3,000 adults demonstrating the efficacy of optimism and perseverance in the reduction of mental illness.
• Learn more about the latest research on mental disorders from the National Institute of Mental Health.