Can natural selection select for genes based on their utility at a group level?

[Martinus]

Plenty of gays end up reproducing. 

Yeah and to the best of my knowledge their children do not have a higher chance of being gay than straight people's children.

Which would example prove my point, wouldn't it, that there isn't a "gay gene", right?

[Martinus]

Plenty of gays end up reproducing.

And yet their offspring is no more likely to be gay than offspring of straight people, which is the point I am trying to make.

[Tamas]

Just for a SECOND I hoped this would be a Marty post NOT about homosexuality. Then I started reading the OP

[Martinus]

Thoughts?

The vast majority of members of an eusocial species do not mate or are sterile, but they are more successful and fundamental to life on this planet than any vertebrate species. Generally speaking, I think it is reasonably fair to suggest that males in social amniote species  is that the females are baby factories and the males are dual purpose worker-drones/provider of genetic material.  No reason that homosexuals can't be a part of this.

Eusocial species share close kin relationships to keep natural selection from breaking down the social order through selfish behavior. Our social amniote species doesn't have anywhere near the degree of kin relatedness (either today or in the distant past) in our social groups of any eusocial species. That is a good reason homosexuals can't be a part of this.

I don't know - remember that the gene would have appeared and selected for before we formed advanced societies, not to mention any civilization. Wouldn't early humans have close kin relationships too?

[Tamas]

Oh and without reading the thread, I kind of thing that homosexuality cannot be purely genetical because it could not survive: altough for the last couple of thousand years it was a social obligation to reproduce, pre-society times it was probably not: if you wanted to fuck females, you took on the alpha male and either won or lost. If you were not interested to boot, you prolly did not bother.

[Martinus]

No idea, however not all of evolution has a specific reason. Not all traits are breed for (or bred against). Many traits are just incidental. Says the gay gene may be tied to another trait. being gay is just co-incidental to this trait. Not all people who have this "good" trait are gay (say recessive gene at it's simplest, though there are many other factors that cause traits to manifest. The "unintended consequence" of gayness at 10% could fall well within the normal die off within a species so that the "good" trait (with gayness attached) doesn't die out. Genetic and evolution is way more complicated the good traits survive, bad traits die off.

Still, I don't think my theory is totally bunk. I mean, at least retrospectively, it seems that having a "drone caste" in a society is beneficial to the society as a whole. It is not a coincidence that a lot of work of art and science came from men who were childless (whether because of their celibacy - religiously ordained or not, homosexuality or another lifestyle choice). Children just take a lot of energy and resources.

[Martinus]

It seems like it would make more sense for a gene to exist to make sure some individuals are sterile.  As after all, homosexuals aren't incapable of creating offspring, their just not inclined towards it.*

Well, I may be grasping for straws here, but if someone was looking for a more "intelligent design" as it were, making them disintrested (but ultimately capable of) creating offspring would work better in a situation when suddenly, due to a demographic upheaval, you don't have enough children and fecund men to keep the population going.

Something like President Roslin declaring a moratorium on abortions, and whatnot.

Essentially, in prosperous, populous societies with high access to resources and low child mortality rate you could "let them be" disinterested thus controlling the population and providing for additional work force that is more "selfless".

In struggling, undeveloped, high child mortality societies you could apply various pressures to make them reproduce.

Which has actually historically happened.

[Martinus]

Gayness is genetic?
I thought studies had proven it was just a small factor?


Thinking of it was...I just can't see a way to make it work unless you tie in homosexuality with submissive behaviour or other such things (which of course isn't so).
I was thinking down lines of only the alpha male being able to breed and so the other straight males would challenge him and die whilst the gays would accept this- but this would still end up with the gays not breeding to prove gayness is a positive attribute....No other ideas come to mind.

The studies has proven that gay people are not more likely to have gay offspring and in that sense it isn't genetic.

However, if you bothered to read my post, you would realize that is exactly not what I am saying.

[Martinus]

X woman and Y man have 6 children, 3 boys, 3 girls.  1 boy is gay.  When X and Y are devoured by sabre tooth tigers, the gay boy can help take care of his siblings and eventually his nieces and nephews, therefore the rest of his family thrives.

What does that have to do with anything?  It is not like the nuclear family was around during the Sabre Tooth tiger days.  I am pretty sure everybody in the group would have helped out.

I was not even denying it might not be somehow advantageous to have gay men (and women....) around I just didn't get the correlation between ferility and gayness thing.

This is an altered menopause argument. Women live beyond menopause because grandmothers can help raise their grandchildren. This is something we know from all cultures. Is there any similar tradition for childless men helping their nieces and nephews? Not that I know of.

Most definitely. It has even been observed in many primitive societies that still exist. And remember - this does not have to be something prevalent today, since we have moved beyond the environment for which our genes evolved.

[Martinus]

Oh and without reading the thread

Yeah, well you didn't need to say that - the rest of your post shows it clearly enough.

[Tamas]

there any similar tradition for childless men helping their nieces and nephews? Not that I know of.

Viking, meet CdM, CdM, Viking.

[Tamas]

Oh and without reading the thread

Yeah, well you didn't need to say that - the rest of your post shows it clearly enough.

I think the post which nailed it is that homosexuality can very well exist 'just because'. Just that it has not died out it does not mean it has any evolutionary function.

[Ideologue]

It seems like it would make more sense for a gene to exist to make sure some individuals are sterile.  As after all, homosexuals aren't incapable of creating offspring, their just not inclined towards it.*

Well, I may be grasping for straws here, but if someone was looking for a more "intelligent design" as it were, making them disintrested (but ultimately capable of) creating offspring would work better in a situation when suddenly, due to a demographic upheaval, you don't have enough children and fecund men to keep the population going.

Something like President Roslin declaring a moratorium on abortions, and whatnot.

That didn't make that much sense, anyway.  A moratorium once planetfall had been acheived would have been logical, but not before that.

What do you think of the notion that homosexuality recurs as a method of preventing potentially destabilizing male-vs-male sexual conflict?

[alfred russel]

Thoughts?

The vast majority of members of an eusocial species do not mate or are sterile, but they are more successful and fundamental to life on this planet than any vertebrate species. Generally speaking, I think it is reasonably fair to suggest that males in social amniote species  is that the females are baby factories and the males are dual purpose worker-drones/provider of genetic material.  No reason that homosexuals can't be a part of this.

Eusocial species share close kin relationships to keep natural selection from breaking down the social order through selfish behavior. Our social amniote species doesn't have anywhere near the degree of kin relatedness (either today or in the distant past) in our social groups of any eusocial species. That is a good reason homosexuals can't be a part of this.

I don't know - remember that the gene would have appeared and selected for before we formed advanced societies, not to mention any civilization. Wouldn't early humans have close kin relationships too?

No--because most eusocial species have haploid/diploid sex differentiation. (haploid only having one set of chromosomes, diploid having 2). For example, in bees males only have one chromosome set (thus are haploid), while females have 2 (are diploid)--humans and most animals are all diploid. The result is that female worker bees are 75% related to their sisters, as opposed to the 50% relation humans are to their true siblings. This means that for a female worker bee, they are actually more related to the members of their hive then they would be to their own offspring, and thus in terms of inclusive fitness have an incentive to favor the other members of the hive over their offspring. This reduces any advantage they would have to "cheat" and "be selfish" by reproducing on their own.

Human biology just doesn't facilitate that level of kin relationship.

Also, I don't buy that evolution hasn't been active to any significant degree since we formed civilization.

[Malthus]

What do you think of the notion that homosexuality recurs as a method of preventing potentially destabilizing male-vs-male sexual conflict?

I think homosexuality could enhance male-vs-male sexual conflict; now in addition to competing with other males for women, males have to worry about competing with other males for each other, not to mention the possibility of being sexually coerced by other men.