Discussion What is the evolutionary reason behind suicidal thoughts?

[kirillbledny]

I often think about this. I get that depression or other mental illnesses aren't agents with goals, but I don't understand what the "point" of having a brain that can generate such thoughts is. If I kill myself, the depression dies along with my brain so what then? You'd think that because survival instinct is found in pretty much all living organisms, such a thought process shouldn't be possible. One thing I thought of is that since a lot of mental illnesses are hereditary, maybe it's a kind of natural selection (ie. someone like me with such shit mental health shouldn't reproduce and pass it on, so nature runs this suicidal ideation scenario to ensure survival of the fittest).

I'd love to hear your guys' thoughts on this, it's a very interesting topic to me and I'm interested in hearing different perspectives.

 

[lostinthecha0s]

The way my therapist describe it is a maladaptive survival response. If trapped with no way of survival, the brain is more likely to take itself out rather than let fate do the work. Like the 9/11 jumpers who didn't want to die in the collapse. However brains are flawed and sometimes can't tell the difference between fighting tooth and nail to survive or just a temporary issue.

Struggled with this personal issue since I was 10 and living in an abusive household, felt powerless to change the situation and felt death was the only way out. Now at 27 any minor inconvenience my first thought is "welp, this is it"

 

[TorturedCerebrum]

I think because we are more intelligent and social animals than the rest, it can be a side effect of high emotional processing and just a byproduct of our intelligence. Since those things are good and overall do help with the survivability of the species, suicide as a derivative isn't large enough to cause our evolutionary systems to weed out those traits that can cause suicidal ideation in some people with different brain chemistry.

I could be wrong though so idk

 

[unluckysadness]

Very good question. As you, I think it may be some natural selection. Lethal diseases can also be considered like natural selection. Too much people on the planet = some people must die because they are dangerous for the planet ? It makes sense in a certain way...

 

[kirillbledny]

The way my therapist describe it is a maladaptive survival response. If trapped with no way of survival, the brain is more likely to take itself out rather than let fate do the work.

This is interesting, sometimes I think about people who live in real poverty or warzones, and I think... why not just end it? I have always thought that if a nuclear war happened, I'd want to go outside and die rather than trying to survive in a bunker eating drywall or whatever. Some people probably just have a very strong will to live, or maybe children/partners who they feel they have to fight/stay for.

Very good question. As you, I think it may be some natural selection. Lethal diseases can also be considered like natural selection. Too much people on the planet = some people must die because they are dangerous for the planet ? It makes sense in a certain way...

I agree. In a way I see suicide as the terminal stage of mental illness. Some people die of cancer, some people die of depression or other such ailments.

I think because we are more intelligent and social animals than the rest, it can be a side effect of high emotional processing and just a byproduct of our intelligence. Since those things are good and overall do help with the survivability of the species, suicide as a derivative isn't large enough to cause our evolutionary systems to weed out those traits that can cause suicidal ideation in some people with different brain chemistry.

I could be wrong though so idk

Yeah, this makes sense to me. If evolution was perfect, there would be no diseases because everyone with one would be taken out. It's like the appendix.

 

[124afun15]

It is more dysfunction than anything. Like asking "what is the evolutionary reason behind cancer"

Completely unnatural and fixable.

 

[pthnrdnojvsc]

evolution is true

but a 1 day old human has only a very few instincts. those are the only things put there by evolution. everything after a human is one hour old that they belive is taught or learned

a 1 day old human knows nothing not even that it is separate from the environment

 

[kirillbledny]

It is more dysfunction than anything. Like asking "what is the evolutionary reason behind cancer"

Completely unnatural and fixable.

Well I'd have the same natural selection argument for cancer or any other illness. Any kind of medical intervention is going against nature. Obviously I'm not arguing we should therefore let people die and suffer just because the illness is natural. You're probably right that I'm trying to find something rational about it, when it just happens, like a tsunami or tornado.

 

[Forever Sleep]

I suppose it's still only a small percentage of the entire population. Plus- some people with depression and ideation still choose to reproduce or- they develop symptoms after becoming parents.

I wonder if most humans have the capacity to develop depression under the right or rather- wrong circumstances. We're living very abnormal lives when you consider our origins.

Zoo animals can exhibit signs of anxiety and depression. We don't diagnose them as being mentally ill though- at least, not initially. We recognise that they are being forced to live in stressful and unnatural environments. So- how much of it really is 'illness' compared to an understandable reaction to our modern environment?

I know what you mean though. I've felt that way about depression. What goal does it serve? Why does it survive in the gene pool? But then- we survive outside of the animal kingdom in a way. We've found 'cheats' to conceive, cheats to evade death.

Whereas the 'weakest' are left to die or are even attacked in the animal kingdom- comparitively speaking, we support 'weak' or ill humans with benefits, healthcare etc. It's almost like we're nurturing ailments in a way. Even when I was a child, there wasn't so much spoken about about mental illness. There would be one or two children with learning difficulties. One or two bullies but, not much was spoken about the causes. It's almost celebrated now.

I've seen YouTube videos where they break down the word: 'depressed' into 'deep rest'. Saying that depression is the way the mind/ body copes with being overloaded. But then- obviously, prolonged isolation probably isn't healthy either. So, maybe what starts out as a healthy coping mechanism goes wrong.

The point being though that depression and ideation isn't necessarily fatal. Especially not with the (relatively) easy availabilty of food, shelter, medicine. So, I suppose it survives long enough for some people to pass it on, through procreation.

I also wonder what our environment is doing to us. I believe they found links with leaded petrol and reduced IQ in former generations. We are breathing and injesting toxins all the time. It wouldn't surprise me if that was affecting our brains/ how we develop in the womb too.

 

[Forveleth]

I do not think this is some sort of natural selection or evolutionary mechanism or outcome. Suicide is what happens to individuals when they are pushed past a mental breaking point. It is the result of a profound hopelessness about ever having any slight positivity in the future. While it has somewhat to do with mental illness, research is finding that the biggest factor in suicidality is social connection and support systems.

I think this is one of those things that extends far beyond nature as a result of the human mind becoming so evolved and high level that it ends up with circumstances that the rest of nature never faced before and has no mechanism built around.

 

[kirillbledny]

I do not think this is some sort of natural selection or evolutionary mechanism or outcome. Suicide is what happens to individuals when they are pushed past a mental breaking point. It is the result of a profound hopelessness about ever having any slight positivity in the future. While it has somewhat to do with mental illness, research is finding that the biggest factor in suicidality is social connection and support systems.

I think this is one of those things that extends far beyond nature as a result of the human mind becoming so evolved and high level that it ends up with circumstances that the rest of nature never faced before and has no mechanism built around.

Yeah it's definitely a multitude of factors and it's hard to say what it is exactly. I think that modern society definitely contributes to it, some statistics from the UK show that 1 in 5 Brits are on antidepressants. Then again, there has been a lot of stigma against mental illness in the past, so is it that people are really more depressed now than 100-200 years ago, or do we just talk about it more openly now? People (in the West) used to be more religious, which automatically provided them with a community of like minded people who would support them through crises, everything is very individualistic now - "don't trauma dump to your friends, pay a therapist to listen to you instead."

 

[bl33ding_heart]

Intelligence is just the natural cause of suicide ideation. The more intelligent one is the more capacity one has to suffer. Humans naturally experience emotional suffering to a significantly higher extent than any animal. Because our intelligence is vastly different than that of an animal, and almost all animals run merely off of instincts. Humans are more suicidal than any creature in existence. Self harm and even suicide has been reported in few animals. But not even close to the extent it is in humans. Because almost all animals just aren't sentient enough to experience emotional pain in the way a human would.

 

[Fadenself00_]

Modern society is so vastly different from everything that came before it.
I would say it's best to think about, how, because most of the things leading to suicide are due to very complex, modern issues, we are currently going through evolution/natural selection.

 

[jdogg60]

Not being able to easily shake off trauma like a deer does after the freeze response, has something to do with it I think. Our complex minds enable us to survive better as a species with technology, but the trade-off is a disruption to that more primitive instinct.

 

[kirillbledny]

Not being able to easily shake off trauma like a deer does after the freeze response, has something to do with it I think. Our complex minds enable us to survive better as a species with technology, but the trade-off is a disruption to that more primitive instinct.

I think there's definitely something to this. When I was looking for EMDR therapy for trauma, the basis of it is that traumatic memories are stored in a different way than regular (even bad memories) are. They compare it to a wound that still has something in it, preventing it from closing and healing normally, and instead staying open and causing painful experiences (such as flashbacks with PTSD).

 

[FluffIsJustice]

I think of it more like an unintended side effect that didn't go badly enough to ruin the entire population and so it just keeps floating around. In biology, there are quite a few things that don't make sense and cause problems but persist simply because it's not bad enough to ruin the species. (as an example, the poor female hyenas who have to give birth)
Additionally, maybe I'm mentioning something unnecessary, but survival of the fittest originally meant that the most well-adapted survive, not the strongest (that is more of a cultural interpretation I think?) and here humans are completely outside the box since we change our environment to suit us instead.
From an evolutionary theory perspective I think I remember it partly being something like - a natural way to deal with individuals who were exiled from the main group and as such will die soon due to predators anyway, but I'm not sure I remember it correctly.

 

[AreWeWinning]

If you're really interested in the evolutionary reasons, you might want to take a look at this paper: A Mathematical Model of Evolutionary Pressures Regulating Self‐Preservation and Self‐Destruction / Suicide and Life-Threatening Behavior, 1986

In short, the theory is that longevity, survival, and self-preservation are not the primary goal of a living organism. The primary goal is reproduction. If an organism's reproductive value is zero, or close to zero, survival in itself has no purpose.

Most of the comments here, and most people in general, try to look at suicide from the perspective of the individual, like self-preservation, the amount of pain the individual can endure, etc. But from an evolutionary perspective, and in terms of the survival of the species, these are secondary. The primary objective is the survival of the species. Survival of the individual and self-preservation are useful only as long as it aids reproduction and the creation of new generations.

Where it gets interesting is when we also start to consider family relationships. At the end of the day, survival of the species = survival of the genes and certain traits encoded in those genes. Close family members share a large portion of their genes. So if I can help a family member survive, that also means some of my genes survive too, since our genes are highly similar. This is why helping and supporting a close family member is a very strong motivator to carry on and survive. The closer the relationship, the stronger the motivation. E.g. parents fight to survive so that they can support their children. Siblings support their nieces and nephews, etc. On the other hand, if the individual has no close family relationships and their reproductive value is zero, there is no reason for them to live anymore.

The paper even has a mathematical formula for the whole thing (click to enlarge):

---

This is also why hopelessness, burdensomeness, or social rejection can trigger suicidal behaviour. To put it bluntly, if I'm not going to have kids, and I'm a burden to my family, then the species is better off if I'm dead. I'm doing others a favour by killing myself. Well, that isn't how most suicidal people feel, but from an evolutionary perspective, that's what nature is trying to say.

This is just a simplified version of the whole idea, of course. The paper is much more detailed.

The way my therapist describe it is a maladaptive survival response. If trapped with no way of survival, the brain is more likely to take itself out rather than let fate do the work. Like the 9/11 jumpers who didn't want to die in the collapse. However brains are flawed and sometimes can't tell the difference between fighting tooth and nail to survive or just a temporary issue.

I think the 9/11 jumpers were trying to escape from the flames, not from the potential collapse of the building. They weren't committing suicide. By jumping, they had a higher chance of survival than being burned alive, and that's why they probably jumped.

 

[kirillbledny]

If you're really interested in the evolutionary reasons, you might want to take a look at this paper: A Mathematical Model of Evolutionary Pressures Regulating Self‐Preservation and Self‐Destruction / Suicide and Life-Threatening Behavior, 1986

In short, the theory is that longevity, survival, and self-preservation are not the primary goal of a living organism. The primary goal is reproduction. If an organism's reproductive value is zero, or close to zero, survival in itself has no purpose.

Most of the comments here, and most people in general, try to look at suicide from the perspective of the individual, like self-preservation, the amount of pain the individual can endure, etc. But from an evolutionary perspective, and in terms of the survival of the species, these are secondary. The primary objective is the survival of the species. Survival of the individual and self-preservation are useful only as long as it aids reproduction and the creation of new generations.

Where it gets interesting is when we also start to consider family relationships. At the end of the day, survival of the species = survival of the genes and certain traits encoded in those genes. Close family members share a large portion of their genes. So if I can help a family member survive, that also means some of my genes survive too, since our genes are highly similar. This is why helping and supporting a close family member is a very strong motivator to carry on and survive. The closer the relationship, the stronger the motivation. E.g. parents fight to survive so that they can support their children. Siblings support their nieces and nephews, etc. On the other hand, if the individual has no close family relationships and their reproductive value is zero, there is no reason for them to live anymore.

The paper even has a mathematical formula for the whole thing (click to enlarge):

View attachment 207712

This is also why hopelessness, burdensomeness, or social rejection can trigger suicidal behaviour. To put it bluntly, if I'm not going to have kids, and I'm a burden to my family, then the species is better off if I'm dead. I'm doing others a favour by killing myself. Well, that isn't how most suicidal people feel, but from an evolutionary perspective, that's what nature is trying to say.

This is just a simplified version of the whole idea, of course. The paper is much more detailed.



I think the 9/11 jumpers were trying to escape from the flames, not from the potential collapse of the building. They weren't committing suicide. By jumping, they had a higher chance of survival than being burned alive, and that's why they probably jumped.

Thank you for the answer, it's very interesting and I'll look into the paper more! This explanation does make a lot of sense. People don't like when you say that reproduction is the entire purpose we're alive, but it's true. It just so happens our brains are developed enough to also study physics or space, or ponder the meaning of life.