You can accept or ignore this, and it won't change the science at all.
"Depression and anxiety are, for the large majority of cases, emotional signals that one’s psychological health is not ideal and that one’s psychosocial/relational needs are not being met."
looks like a theory and and experimentally testable and falsifiable one at that. Take a bunch of depressed people, try to fix their relationship needs along the lines mentioned in the article, survey the people who now have friends, get on with their family and so on and see if they are still depressed and compare to a control group. Simples.
And almost no ones social needs are ever truly completely met. we also know already that social support helps anxiety and depression regardless of whether it is a root cause. So your test wouldn't falsify if it returned a negative value, nor support with a positive correlation.
The wonderful thing about scientific progress is that it shrinks the space quacks and charlatans have to peddle their pet theories and cures.
I think that suicide could have some evolutionary advantage in a group. Say there is a member of a group who has become sick, injured, or otherwise incapacitated and is unable to contribute to the group. The group must spend more work to take care of the member than they receive back from the individuals paltry, or nonexistent contributions to the group. If the member's ailment is temporary, then it would be advantageous for the group to bear the burden of taking care of the member, as they would benefit more in the long run.
However, if the member's condition is more permanent, then they represent a net loss to the group's well-being. It would then benefit the group as a whole if that member were to commit suicide, eliminating their burden from the group.
I think this is something that many individuals with suicidal ideation feel on some level. They think that they cannot contribute to their group (family, friends, job, community, country, etc), and that their lack of contribution will be indefinite. For example, a person with anxiety so bad that they are unable to leave the house or get a job might feel like a burden to their family, and unable to contribute. Or, a person with depression might have such a low opinion of themselves that they are unable to see the contributions they are making, or think that their contributions are meaningless and so feel like they are not contributing anything at all worthwhile.
Even though suicide could have had evolutionary advantages in the earlier days of human existence, in modern times I don't think this is the case any longer. With modern medicines and technologies, medical conditions are not as crippling as in the past, and there are more ways to contribute to a group than ever, even without being able to walk or leave the home. The difficulty would then seem to be either helping the suicidal individual to find a group and method of worthwhile contribution, or helping the individual to understand the ways they are already contributing to a group and why that contribution is worthwhile.
Of course, this is just a baseless theory of mine, and I would be very curious to see if there is any actual evidence to back this up.
Sounds like archives of Sarah Perry’s The View from Hell[0] may be something you’d interested in checking out. She touches upon a range of suicide-related topics and provides references for further reading.
It seems like any characteristic that prevents the individual from reproducing is by definition not selected for. But I could be misunderstanding something.
Maybe it could work in the case of people who are already parents. Favoring the group could increase the likeliness of their children surviving perhaps?
I believe there is similar thinking for genetic passing of traits like homosexuality.
Even if some individuals in the group do not reproduce, their relatives in the group do reproduce. So say 1 person self-sacrifices and does not reproduce, and as a result of their sacrifice 10 others in the group survive and reproduce that would not have been able to if the first individual had not self sacrificed. The family all has gene A, so this results in a net gain of 9 individuals with gene A. So the amount of people with gene A increases, even though some individuals with gene A potentially do not survive and reproduce.
If you want to learn more about this kind of thing, look into "Selfish Gene Theory".
Suppose we did not separate these things. In that case, for an entire group to have A, that implies that some ancestor of that entire group had A. But this contradicts the premise that the gene makes people less likely to reproduce.
It works if you accept the idea that genes which are fit in some situations are less fit in others. In that case you could have a person who developed this mutation of feeling suicidal when they feel useless, but it doesn't "activate" because they aren't in a situation where they feel useless. But once a whole group has this gene, then your theory of propagation through siblings/cousins is more plausible.
The example frequently citied in this area is sickle cell anaemia, which can be inadvertently selected for in areas where Malaria is common. Having one 'bad' gene protects the person from Malaria, having two means that one has sickle cell anaemia.
This means that people with a single gene are more likely to survive, and hence pass on their gene, but this sometimes manifests as someone with sickle cell anaemia. See https://en.wikipedia.org/wiki/Sickle-cell_disease#Epidemiolo...
> if you reach a certain age and are not already a parent, it means you're deficient. It's better for the gene pool if you die without reproducing.
This explanation makes no sense to me. Evolution doesn't select for the overall gene pool AIUI, it selects for fit individuals. I can't see how, even in theory, this explanation would be plausible.
> If you're a parent and you did all that was needed for the offspring to survive the early development period, you're no longer needed and probably better off dying instead of consuming resources your children need.
This explanation sounds at least mathematically plausible to me.
By your logic, males should be continuously fathering offspring throughout their lives, as soon as they reach puberty.
If the answer is that they come to the conclusion of suicide because they are deluded by depression, it comes back to the question in the OP: how does the grandparent's hypothesis explain the symptom of suicidal ideation/acts in depression?