Depression Had Adaptive Value For Our Ancestors. Maybe It's Adaptive For Us, Too.

Depression Had Adaptive Value For Our Ancestors. Maybe It's Adaptive For Us, Too.

I like to believe that every modern-day affliction and illness once had adaptive and evolutionary value, or else it that affliction wouldn't exist in the first place.


I like to believe that every modern-day affliction and illness once had adaptive and evolutionary value, or else it that affliction wouldn't exist in the first place. Well, in the spirit of the New Year, there is none better than depression, not only so we can understand what use it may have once had to our ancestors, but rather why, from an evolutionary standpoint, depression exists in the first place. As suicide kills more people every year than murder and war combined, I believe it is imperative for us to get to the bottom of one of the world's most devastating illnesses.

Depression is known to run in families, and it is no surprise that depression and mental illness have genetic components to them. To our surprise, however, researchers Andrew Miller and Charles Raison, physicians at Emory University and the University of Arizona, respectively, have proposed that the same genes that increase a person's risk for depression also enhance immunity to infections. "Most of the genetic variations that have been linked to depression turn out to affect the function of the immune system," Miller said. The hypothesis is that these genes were adaptive in helping people not die of infection in a world where life expectancy was significantly lower.

It's no surprise that afflictions like depression, anxiety, and mental illness have been more prevalent in our modern-day age. The current life expectancy in the U.S. is 78.7 years, compared to the approximate 40-year-old life expectancy of pre-industrial England. Without infections like tuberculosis and pneumonia to worry about, it is unsurprising that people have more time to be depressed in our modern era.

The genes that have a predisposition to depression are mutated variations of the "NPY" gene. Mutated versions of the gene allowed our ancestors to have increased inflammation, especially in early childhood when we are most vulnerable to infection. As individuals with the mutated NPY gene were more likely to survive, more and more copies of the gene were passed on to their offspring.

Recently, researchers at the University of Michigan found that people with depression were more likely to have a mutated NPY gene. Functioning normally, the gene codes for a neurotransmitter that increases tolerance to stress and made us less likely to be depressed. In ancestral environments, however, the trade-off for extended survival was often depression. According to Miller and Raison, acute stress was usually linked to physical harm or wounds, most of which led to death, or infections that easily led to death. As a result, evolution favored the selection of individuals with immune systems that operated under a "smoke-detector principle," a principle that reacted readily to false alarms of infection as well as actual infection.

"Immune responses to acute stress are typically not necessary -- not every stressful situation results in a wound and infection. However, if our ancestors became wounded even a single time and didn't experience a piqued immune response, they might die from an infection," writes Brian Gabriel of The Atlantic.

According to Miller, depressive symptoms like social withdrawal, and loss of energy were once advantageous to our ancestors. A loss of energy often was a symptom of the body using all of its energy to fight infection. Social withdrawal often was a symptom of avoiding exposure to additional infectious agents. Recently, the two researchers have worked on targeting inflammation to treat depression, with varying degrees of success. In patients with elevated inflammation, a drug that disrupted communication between immune cells worked.

I have said it before, but the findings in the Andrews and Raison study support the claim that depression is not a sign that something is wrong with you, even from an evolutionary standpoint. Like for our ancestors, depression, even now, is a sign that there is a situation or infection so serious that we need to devote all our energy to battling it and withdraw from others to avoid further damage or harm. We suffer when depressed, but we do not do so in vain.

Although it is a stretch to name any advantages of depression, two other researchers have shown that rumination, the foremost symptom and cause of depression, may lead to improved outcomes in our modern lives. Andy Thomson of UVA and Paul Andrews of VCU have found that the awful symptoms of depression "reduced the possibility of becoming distracted from the pressing problem." We need to pay attention to what underlies our depression. Say a family member just died or you went through a divorce: who wouldn't ruminate about those pressing life events? "Human attention is a scarce resource -- the neural effects of depression make sure the resource is efficiently allocated." The result is, because of our ruminations, we become much more analytical and deliberate in our thought processes.

Many people may see the two research papers' findings about the advantageous and evolutionary values of depression to be mere justifications for human suffering. It is true that these evolutionary and adaptive theories about depression only apply when an identifiable stressor is causing the illness. We know that sometimes depression can strike for seemingly no reason. But normalizing is not romanticizing, and I do not see a world where drugging away our problems is a feasible means of advancing the human species forward. I do not question that medication is the best way to treat some people afflicted with depression, but it is not the only way.

Sadness and unpleasant emotions do have their benefits: psychologist Joe Fargas has recently found that negative moods lead to better decisions in more complex situations. Paul Andrews later found that negative moods led to improved analytical abilities. Depressed people were found to think better. But "that is the paradox of evolution: even if our pain is useful, the urge to escape from the pain remains the most powerful instinct of all."

Thomson has one anecdote about how his theory of rumination has affected his medical practice. He has cut down significantly on antidepressant prescriptions because he believes the drugs can interfere with genuine recovery. One patient came in and requested a reduced dosage of antidepressants. The antidepressants were working great, and in fact, the patient told him that "I feel so much better." However, she also told him "I'm still married to the same alcoholic son of a bitch. It's just now he's tolerable."

There is usually a reason for depression and something behind it, even if that reason is not something we can see in the moment. It is a message to ourselves that our needs aren't being met. Part of fighting depression is by identifying a single problem, or perhaps the many problems we need to solve, and then making a long-term plan to solve them. It is a long, difficult, and tedious path, and at times it seems impossible, but the role of most therapists and counselors is so we know we do not face these problems isolated and alone, that we have guides who will walk with us on our journeys.

Maybe, today, after all, depression is adaptive, too.

Popular Right Now

To The Person Who Feels Suicidal But Doesn't Want To Die

Suicidal thoughts are not black and white.

Everyone assumes that if you have suicidal thoughts that means you want to die.

Suicidal thoughts are thought of in such black-and-white terms. Either you have suicidal thoughts and you want to die, or you don't have suicidal thoughts and you want to live. What most people don't understand is there are some stuck in the gray area of those two statements, I for one am one of them.

I've had suicidal thoughts since I was a kid.

My first recollection of it was when I came home after school one day and got in trouble, and while I was just sitting in the dining room I kept thinking, “I wonder what it would be like to take a knife from the kitchen and just shove it into my stomach." I didn't want to die, or even hurt myself for that matter. But those thoughts haven't stopped since.

I've thought about going into the bathroom and taking every single pill I could find and just drifting to sleep and never waking back up, I've thought about hurting myself to take the pain away, just a few days ago on my way to work I thought about driving my car straight into a tree. But I didn't. Why? Because even though that urge was so strong, I didn't want to die. I still don't, I don't want my life to end.

I don't think I've ever told anyone about these feelings. I don't want others to worry because the first thing anyone thinks when you tell them you have thoughts about hurting or killing yourself is that you're absolutely going to do it and they begin to panic. Yes, I have suicidal thoughts, but I don't want to die.

It's a confusing feeling, it's a scary feeling.

When the depression takes over you feel like you aren't in control. It's like you're drowning.

Every bad memory, every single thing that hurt you, every bad thing you've ever done comes back and grabs you by the ankle and drags you back under the water just as you're about the reach the surface. It's suffocating and not being able to do anything about it.

The hardest part is you never know when these thoughts are going to come. Some days you're just so happy and can't believe how good your life is, and the very next day you could be alone in a dark room unable to see because of the tears welling up in your eyes and thinking you'd be better off dead. You feel alone, you feel like a burden to everyone around you, you feel like the world would be better off without you. I wish it was something I could just turn off but I can't, no matter how hard I try.

These feelings come in waves.

It feels like you're swimming and the sun is shining and you're having a great time until a wave comes and sucks you under into the darkness of the water. No matter how hard you try to reach the surface again a new wave comes and hits you back under again, and again, and again.

And then it just stops.

But you never know when the next wave is going to come. You never know when you're going to be sucked back under.

I always wondered if I was the only one like this.

It didn't make any sense to me, how did I think about suicide so often but not want to die? But I was thinking about it in black and white, I thought I wasn't allowed to have those feelings since I wasn't going to act on them. But then I read articles much like this one and I realized I'm not the only one. Suicidal thoughts aren't black and white, and my feelings are valid.

To everyone who feels this way, you aren't alone.

I thought I was for the longest time, I thought I was the only one who felt this way and I didn't understand how I could feel this way. But please, I implore you to talk to someone, anyone, about the way you're feeling, whether it be a family member, significant other, a friend, a therapist.

My biggest mistake all these years was never telling anyone how I feel in fear that they would either brush me off because “who could be suicidal but not want to die?" or panic and try to commit me to a hospital or something. Writing this article has been the greatest feeling of relief I've felt in a long time, talking about it helps. I know it's scary to tell people how you're feeling, but you're not alone and you don't have to go through this alone.

Suicidal thoughts aren't black and white, your feelings are valid, and there are people here for you. You are not alone.

If you or someone you know is experiencing suicidal thoughts, call the National Suicide Prevention Hotline — 1-800-273-8255

Cover Image Credit: BengaliClicker

Related Content

Connect with a generation
of new voices.

We are students, thinkers, influencers, and communities sharing our ideas with the world. Join our platform to create and discover content that actually matters to you.

Learn more Start Creating

In Real Life, 'Plus Size' Means A Size 16 And Up, Not Just Women Who Are Size 8's With Big Breasts

The media needs to understand this, and give recognition to actual plus-size women.


Recently, a British reality dating TV show called "Love Island" introduced that a plus-sized model would be in the season five lineup of contestants. This decision was made after the show was called out for not having enough diversity in its contestants. However, the internet was quick to point out that this "plus-size model" is not an accurate representation of the plus-size community.

@abidickson01 on

Anna Vakili, plus-size model and "Love Island "Season 5 Contestant Yahoo UK News

It is so frustrating that the media picks and chooses women that are the "ideal" version of plus sized. In the fashion world, plus-size starts at size 8. EIGHT. In real life, plus-size women are women who are size 16 and up. Plunkett Research, a marketing research company, estimated in 2018 that 68% of women in America wear a size 16 to 18. This is a vast difference to what we are being told by the media. Just because a woman is curvy and has big breasts, does NOT mean that they are plus size. Marketing teams for television shows, magazines, and other forms of media need to realize that the industry's idea of plus size is not proportionate to reality.

I am all for inclusion, but I also recognize that in order for inclusion to actually happen, it needs to be accurate.

"Love Island" is not the only culprit of being unrealistic in woman's sizes, and I don't fully blame them for this choice. I think this is a perfect example of the unrealistic expectations that our society puts on women. When the media tells the world that expectations are vastly different from reality, it causes women to internalize that message and compare themselves to these unrealistic standards.

By bringing the truth to the public, it allows women to know that they should not compare themselves and feel bad about themselves. Everyone is beautiful. Picking and choosing the "ideal" woman or the "ideal" plus-size woman is completely deceitful. We as a society need to do better.

Related Content

Facebook Comments