It’s only in the last 150 or so years that we expect all people to be Rational Economic Agents. If anything, I think /that/ is something that will get trimmed pretty quickly from the tree…
Genes in Conflict: The Biology of Selfish Genetic Elements
by Austin Burt and Robert Trivers
https://www.amazon.com/gp/product/0674027221/
However, referring to the original article of this thread, it is also possible that the same genes that give us depression also give us something positive, such as creativity.
There are perfectly plausible reasons why the conditions we regard as mental illness are adaptations that help evolutionary fitness:
- Depression puts one into a low-energy, contemplative state that enables reflection, healing and formulation of reformed ways of thinking and being ("dark night of the soul");
- Bipiolar is a pattern of swinging between high-energy bursts of inspiration and creation, and low-energy states of recuperation and reflection;
- Schizophrenia is a way of disassociating from real-world experiences that are too painful to experience with normal consciousness, and is a preferable alternative (from an evolutionary perspective) to suicide, buying time for processing and healing to take place, given the right kind of support.
Of course, that could be seen as a "just so" story too. Except that evolutionary theory says that only genes that promote evolutionary fitness should survive and spread through the genome, particularly given that replication of any given gene carries a significant cost. We can also easily observe that conditions like depression and schizophrenia normally develop in response to a trigger - i.e., a traumatic life event or extended period of abuse.
So, it's far less of a confected story to just accept that these conditions have been retained in the genome for the reason that makes most sense according to evolutionary theory: it's evolutionarily beneficial for them to be there.
Promoter genes are also part of evolutionary theory. You seem to think evolutionary theory came to an end in 1882. But a lot has happened since then.
I’ve done multiple Google searches and even done Google Books searches in the very book you linked, for the exact phrase “promoter gene”, and it really doesn’t seem to be a term that’s used, at all, really.
DNA promoters are well recognized, but not in the context you’re talking about.
I can very much understand the notion that genes may act to further their own propagation at the cost of the host’s fitness - sure.
It’s just that we first need to see evidence that it’s happening, by having a clear definition of what favours vs costs the host’s fitness.
The hypothesis you’ve cited (and from the book reviews it seems even the authors concede their hypotheses are highly speculative), seems to start with the assumption that these mental illness traits are opposed to the host’s fitness and confer no benefits whatsoever.
But all we have to do is point out the many cases in which these traits actually do benefit the host, which I did and you even conceded in the last line of your comment, and the hypothesis is void.
It reminds me of the “junk DNA” hypothesis, where researchers couldn’t find an obvious use for large sections of the genome so just assumed it to be useless and called it “junk”, only to be later found to have very important roles:
https://medicine.yale.edu/news/yale-medicine-magazine/articl...
https://www.quantamagazine.org/the-complex-truth-about-junk-...
Ancient population suffers from massive viral load, causing such catastrophic damage that the whole surviving population carries some of the viral DNA fragments with it to this day.
Being alive is the reward.
If they've even lived long enough, no absolutely not. Unless you think someone who is routinely depressed is 'vigilant'.
[Hypo]mania is not the primary state of a bipolar patient. Can't speak to schizophrenia, but for those I've seen with that illness, functioning isn't their primary state, either.
Thinking mania can be controlled like an on-off switch.
Why even bother posting?
And someone who experiences mania indicates an uncontrolled illness. Depression and mania prevent normal functioning. You seem to believe an unmedicated bipolar individual is a functional individual with some inkling of rational thought that could 'go into battle with no fear'.
If you don't know, don't post. And you don't know.
I don't know where you are getting the notion that I am saying that mania is rational or controllable. I was speculating based on personal experience around high stress situations. I do not understand why you are choosing to attack the notion that there could be evolutionarily advantageous benefits conferred upon the group.
Edit: we agree that I am speculating. I disagree with you that I have no right to speculate