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← Where Does Homosexuality Fit In The Evolutionary Process?? (PLEASE HELP!)

Where Does Homosexuality Fit In The Evolutionary Process?? (PLEASE HELP!) - Comments

devzoo's Avatar Comment 61 by devzoo

Hi Bonzai,

I completely agree with you that it's a mistake to assume that homosexuals are any more nurturing than heterosexuals. My own version of the "gay uncle/aunt theory," though, doesn't make that assumption.

My starting point is that there is no real difference between homosexuals and heterosexuals, except that generally speaking homosexuals have an attraction to the same sex and not the opposite sex. I don't think this is an "invalid universalization of our own cultural peculiarities."

Nowhere in any of my posts have I stereotyped gays. I have made the assumption that our ancient homosexual ancestors would have produced fewer offspring. I'm not subscribing to a stereotype; I'm thinking logically about how homosexuality must have evolved in early homo sapiens, before our ancestors developed language/religion/etc. In the last few thousand years there have been cultural pressures on homosexuals to mate, but if we rewind much further back, our ancestors would have been free to follow their mating instincts just as all animals do, and for the most part homosexuals would not willingly have entered into straight sex.

Here in a nutshell is what I am saying:

If there is a genetic component to homosexuality, and if homosexuality reduces an individual's chances of reproducing, and if there is some benefit to having a few non-reproductive adults within a cooperative family, then it's logical that homosexuality would be naturally selected. The genetic proclivity for homosexuality would be carried forward by nieces and nephews. I'm not saying this is the only way that homosexuality can be explained, but to me it seems like a valid theory.

IMO, your shitty algebra book is a hugely bad example, because it introduces a designed object into a discussion of evolution, where design has no place. In evolution, a shitty algebra book that serves as an excellent window cushion CAN propagate, because if it accidentally serves a useful purpose at a reasonable cost it gets selected.

I am not a scientist, and so I'm sensitive to the accusation that this theory is pseudo-science. I have a layman's understanding of evolution, so you're right that I may have an overly simplistic understanding of "the relationship between genes and traits and role of selection in building an organism." I can't really refute that. I am encouraged that I might not be so off-track, though, when I hear scientists whom I respect put forward similar arguments. See the following video in which Richard Dawkins, who is a scientist and understands evolution as well as anybody, tackles the subject:

http://www.youtube.com/watch?v=MHDCAllQgS0

Is Dawkins politically motivated in suggesting his version of the gay uncle theory? Perhaps, but it doesn't really matter why he is making the argument, it just matters if the argument is sound, right?

BTW, I've enjoyed your posts and am nodding in agreement over much of what you're saying. I like everything you said in your last post starting with the sentence, "So let's address the politics."

What is your own best guess as to why there are homosexual humans? I'm asking for a guess here, so a little pseudo-science will be tolerated. :)

Thu, 17 Jun 2010 10:25:46 UTC | #481084

Bonzai's Avatar Comment 62 by Bonzai

Comment Removed by Author

Updated: Thu, 17 Jun 2010 13:25:28 UTC | #481108

Bonzai's Avatar Comment 63 by Bonzai

devzoo

Nowhere in any of my posts have I stereotyped gays.

Not you personally, I am sorry if I wasn't clear. I was talking about the "nurturing uncle" story. It is plainly based on two stereotypes. 1) Women are more nurturing 2) gay men are kind of like women. There is not a shred of evidence supporting it, as noted above.

I'm thinking logically about how homosexuality must have evolved in early homo sapiens, before our ancestors developed language/religion/etc. In the >last few thousand years there have been cultural >pressures on homosexuals to mate, but if we rewind much further back, our ancestors would have been free to follow their mating instincts just as all animals do, and for the most part homosexuals would not willingly have entered into straight sex ...

I think the argument is circular. Homosexuality would be subjected to selection only if it is genetic, i.e. there is a homosexual gene to be selected. If not, then this whole argument goes down the flame. As of now there is not a shred of hard evidence that there is a gay gene which is subjected to selection.

The most reasonable explanation to my mind is that it is the result of hormonal condition in the womb. If that is true, then homosexuality is not directly selected, it is a by product of something else, say the hormonal feed back mechanism of pregnant women, which may be selected. In that scenario it just doesn't make sense to ask what is the selective advantage of homosexuality in isolation.

Now whether it is because of cultural pressure or other reasons, homosexuals do have offsprings and siblings, if homosexuality is genetic, you should be able to show that children or siblings of homosexuals are more likely to be homosexuals, controlled for other factors such as socialization. I am not aware of any such study or finding.

There are some studies of so called "gay brains". But again there are multiple fallacies involved in interpreting the data. If you learn a new language or acquire a new skill, that too will show up in the brain's wiring. An important part of neuroplasticity research involves mapping out the structural changes of the brain as a result of new acquired behaviour. So if some self identified homosexuals turn out to have different brain structures, it is not an evidence that they were "born that way", let alone that it is genetic (being "born that way" and being genetic are not the same, if your mother abused alcohol during pregnancy you would probably be born with fetal alcohol syndrome but there is nothing genetic about it)

As I have indicated before is not very clear who are the homosexuals. My feeling is that human sexuality is more plastic and vary than this simplistic model of binary, unchanging sexual orientations can capture. This is supported by data in anthropology and history. Our way of thinking about sexuality is largely a reflection of our own cultural myopia and my problem with so many so called "evolutionary" explanations is that, --regardless of whether the conclusions are right or wrong,--their chain of reasoning is obviously invalid, which involves making many assumptions about homosexuals and homosexuality by extrapolating from our own culture as if it is universal.

So, yes, again at the risk of being politically incorrect, I think to a larger degree than we would like to admit, sexual preference can be an acquired taste and in our society there is a pressure for people to "pick a team and stay with it" so sexual orientation would appear to be more rigid than it really is.

It is fashionable to say so and so (fill in your favorite historical character) was gay,but this is imposing our own view on sexuality on history. Guys like Alexander the Great and the famous Renaissance masters basically fucked anything that walked. It would be very misleading to call these people "gay" (Aside: Michael Angelo was just a miserable man with extremely poor hygiene who hated women, that didn't make him gay.)

A big problem I have with all the pseudo scientific speculations on homosexuality's supposed selective benefit is that aside from not being supported by any evidence and sounding completely made up just to rationalize certain a priori dogmas, they really have nothing to do with homosexuality at all! These are really speculations for why it might be advantageous for not having offsprings. It could be used to "explain" conditions ranging from sterility, frigidity, low sperm count to having a limb dick, to the existence of religious sects that teach celibacy! Well, I am afraid that is pretty lame (no pun intended)

I think it is not true that there is a selective reason for every trait even if a trait has a genetic basis. Pan selectionism is not science, but a sectarian dogma of certain school of evolutionary biologists. What is the selective advantage of being left handed or bald? Unlike homosexuality, baldness and left handedness do appear to be genetic (the genes that are responsible for left handedness and baldness are responsible for something else too, those other traits may have a selection significance)

My textbook example is a very good one. But no analogy is 100% accurate or it wouldn't be an analogy. To understand an analogy properly you have to look at it the right way instead of focusing on side issues that are only incidental to the analogy. The textbook being designed is an incidental feature. The point is that just because you can deploy something for a particular function it doesn't follow that the thing exists for performing that function. If you cannot help being distracted by the fact that the book is manufactured, consider my other example. Old people, slow people and people with feeble physiques act as helpers in wars. But it doesn't follow that being old, slow and weak are selected trait to ensure that we have enough helpers in battles.

P.S. The previous post was deleted due to double posting.

Updated: Thu, 17 Jun 2010 13:43:40 UTC | #481112

bendigeidfran's Avatar Comment 64 by bendigeidfran

Individuals don't matter. Gay genes - whatever combo they are - can breed fine as they're in straight bodies too. Don't need the uncle theory. Doesn't kill you and anyway even lethal genes make it through the filter. If 90% of the popn were gay there'd be something to explain.

Thu, 17 Jun 2010 14:33:55 UTC | #481131

bendigeidfran's Avatar Comment 65 by bendigeidfran

Is it natural? Well it's not supernatural is it?

Thu, 17 Jun 2010 14:37:55 UTC | #481133

devzoo's Avatar Comment 66 by devzoo

Ok, Bonzai, you've convinced me that the gay uncle theory is weaker than I supposed. The best point you made IMO is this one:

These are really speculations for why it might be advantageous for not having offsprings. It could be used to "explain" conditions ranging from sterility, frigidity, low sperm count to having a limb dick, to the existence of religious sects that teach celibacy!

Yes, you're right about that.

Thu, 17 Jun 2010 20:25:01 UTC | #481218

Nick1964's Avatar Comment 67 by Nick1964

Maybe homosexuality is natures way of controlling population. Can you imagine if all the millions of gay people on the planet also had children. The earths population would be enormous. Rather than condemning homosexuality, people should be grateful of it as the population would be out of control. Obviously religions hate gays because they cannot reproduce and expand their religious adherents. It's not rocket science.

Tue, 22 Jun 2010 15:44:48 UTC | #482687

chapmandg's Avatar Comment 68 by chapmandg

Re: "natures way of controlling population": the question remains, though, how the gene for homosexuality (if there is one) is passed on. If homosexuals aren't having children, their genes aren't passed on. So the "natures way of controlling population" theory is not a Darwinian explanation.

As for the "gay uncle" theory and similar theories: why would this promote a gay gene, rather than an asexual gene?

Sun, 27 Jun 2010 07:56:22 UTC | #484006

chapmandg's Avatar Comment 69 by chapmandg

Comment 33 by phil rimmer :

Consenting gay sex is as free and clear as heterosexual sex, and for that matter, contains no different activities.

And fewer consequences.

Sun, 27 Jun 2010 08:12:33 UTC | #484010

bendigeidfran's Avatar Comment 70 by bendigeidfran

Comment 68 by chapmandg

Nature goes for max popn.

The 'gay genes' are in the breeders too.

I'm noy gay but I shagged a man who was.

Sun, 27 Jun 2010 09:25:49 UTC | #484024

Corylus's Avatar Comment 71 by Corylus

Comment 68 by chapmandg :

As for the "gay uncle" theory and similar theories: why would this promote a gay gene, rather than an asexual gene?

You get oxytocin release with orgasm. This brain chemical helps us to emotionally bond with others. This could have an effect on social interactions and thus survival of a kin group. (N.B. I am speculating here)

I doubt it is just that though, there are other issues at play (there must be or asexuality would not exist) - like the question of whether having some members of a kin group not reproduce at certain times (for example, when food it limited) might be advantageous.

Sun, 27 Jun 2010 09:55:15 UTC | #484026

NakedCelt's Avatar Comment 72 by NakedCelt

I'm sorry, Bonzai, but three separate things you've said have struck me as interesting misunderstandings:

Gays are not sterile, and historically most did have children because having children had nothing to do with love or sexual fulfillment, the same was true with most heterosexual marriages in the past. Having children was a duty. You found sexual fulfillment in having affairs, that is, if you were a man and had money or if you were a women and didn't get caught.

No. This is largely true of the patriarchal civilizations of the last few thousand years; however, over the course of human existence, these are a novelty. Most of our evolution happened in small foraging bands, which are very different.

Even in the patriarchal civilizations, a gay person would probably have heterosexual sex less often than a straight person, because it would be less pleasurable. "Less often", persistently through the generations, is quite enough to eliminate any genes involved over time -- if that's all that's going on.

Homosexuality would be subjected to selection only if it is genetic, i.e. there is a homosexual gene to be selected. If not, then this whole argument goes down the flame. As of now there is not a shred of hard evidence that there is a gay gene which is subjected to selection.

The most reasonable explanation to my mind is that it is the result of hormonal condition in the womb. If that is true, then homosexuality is not directly selected, it is a by product of something else, say the hormonal feed back mechanism of pregnant women, which may be selected. In that scenario it just doesn't make sense to ask what is the selective advantage of homosexuality in isolation.

Everything in a biological system happens by means of enzymes; enzymes are directly created by genes. Ergo, everything in a biological system is affected by genes. Of course the functioning of enzymes is exquisitely dependent on environmental conditions -- can we please, please, get past the idea that genes and environment are somehow opposing hypotheses?

It is technically possible in principle that every variant enzyme coded for by every allele at every locus in the human genome has exactly the same ultimate effect on the individual's sexual preferences... but it's not very likely.

People have sex, peroid. Sometimes with partners of the same sex, some times with partners of the opposite sex and sex serves all sorts of purposes besides procreation. We are most like bonobos in sexual behaviour, we are not like penguins or goats.

No, we're not. We are very, very different from bonobos in that we form exclusive or near-exclusive sexual partnerships which last for years at a time. That puts us with gibbons and marmosets, except that they defend territories as pairs -- they are not integrated into a larger society. No other primate besides us lives in a society composed of near-exclusive sexual pairs. Penguins, on the other hand, do.

Wed, 07 Jul 2010 01:50:29 UTC | #486860

bendigeidfran's Avatar Comment 73 by bendigeidfran

Comment 72 by NakedCelt

(no-space-bar-yet)

Nurture-is-nature.Can-extend-this-to-extended-nature-nurture-i.e.inanimate-objects.

Bonzai's-usually-right-when-he-has-a-pop-at-over-deterministic-over-simplified-selectionism.And-usually-a-bit-harsh-on-evo-psych.etc.Because-it's-not-something-Feynman-ever-said.

Wed, 07 Jul 2010 03:41:42 UTC | #486879

bendigeidfran's Avatar Comment 74 by bendigeidfran

He-doesn't-like-philosophy-either.

Wed, 07 Jul 2010 03:43:31 UTC | #486881

bendigeidfran's Avatar Comment 75 by bendigeidfran

Homophobics-breed-more-overall.I-have-been-100%-discrininatory-in-this-regard.Laurie-Fraser-and-the-'sleep-walking'-incident-doesn't-count.I-had-my-fingers-crossed.

Doesn't-matter-as-it's-so-far-twixt-genes-and-Jeans-we-can-fix-it-at-the-level-of-culture.

Wed, 07 Jul 2010 03:52:30 UTC | #486885

mmurray's Avatar Comment 76 by mmurray

You're looking dashing these days Bendi.

Michael

Wed, 07 Jul 2010 04:06:23 UTC | #486887

bendigeidfran's Avatar Comment 77 by bendigeidfran

Comment 76 by mmurray

Wine-in-the-keyboard!

I-think-it's-holding-out-for-some-cheese.

Wed, 07 Jul 2010 05:47:35 UTC | #486897

bendigeidfran's Avatar Comment 78 by bendigeidfran

OP-by-Ben

'Natural'-is-for-selling-shampoo.

It-exists-mostly-because-it-can.If-it-were-90%-homosexuals-we'd-have-something-to-explain.No-new-appendages-appear-to-be-required.Works-fine.Your-lusty-genes-are-doing-great-in-their-eyes-if-you're-getting-any-action.I-once-fell-in-love-with-a-hole-in-a-tree.

'Suicidal-genes'-make-it-fine-too.And-other-lethal-ones.Careless-Darwin.

Lust-and-love-are-generally-wired-in-deep-and-the-rest-is-a-bit-loose.Your-'gay-genes'-such-as-we-might-at-a-stretch-call-them-are-in-breeding-bodies-too-and-get-through-fine-at-a-lower-frequency.

There-is-a-little-part-of-me-inside-you.How-do-you-like-it(qm)

Wed, 07 Jul 2010 06:15:49 UTC | #486899

bendigeidfran's Avatar Comment 79 by bendigeidfran

What-percentage-are-you-after(qm).I-don't-think-there's-as-many-binaries-as-the-surveys-say.They-probably-ask-'What-do-you-identify-as'-or-something-daft-like-that.

Got-to-factor-in-badlight-beer-and-boredom.

Wed, 07 Jul 2010 06:42:49 UTC | #486904

NakedCelt's Avatar Comment 80 by NakedCelt

Buy a new keyboard, bendigeidfran. Now.

Thu, 08 Jul 2010 04:26:55 UTC | #487228

NakedCelt's Avatar Comment 81 by NakedCelt

Your-'gay-genes'-such-as-we-might-at-a-stretch-call-them-are-in-breeding-bodies-too-and-get-through-fine-at-a-lower-frequency.

At a consistently lower frequency through the generations -- that's the exact opposite of "fine". That, in Darwinian terms, is by definition "fucked". Unless it is not, in fact, at a consistently lower frequency through the generations.

Thu, 08 Jul 2010 04:51:07 UTC | #487230

irate_atheist's Avatar Comment 82 by irate_atheist

Comment 80 by NakedCelt -

Buy a new keyboard, bendigeidfran. Now.

Bendigeidran's got a new washing machine and is going to try it on 'Fast spin'.

He hopes that will fix the problem.

Thu, 08 Jul 2010 15:24:42 UTC | #487305

root2squared's Avatar Comment 83 by root2squared

ALT plus 32 (NumPad) will also print a space in Windows I think.

Thu, 08 Jul 2010 20:02:16 UTC | #487346

Milagros_Liller's Avatar Comment 84 by Milagros_Liller

Here's a video in which Richard Dawkins gives some evolutionary reasons for homosexuality: http://www.dailymotion.com/video/xd34et_richard-dawkins-explains-origins-of_gaylesbian

Enjoy

Sat, 25 Sep 2010 12:59:33 UTC | #524696

elenaripoll's Avatar Comment 85 by elenaripoll

We are all a little bit Gay even if not sexually attracted to the opposite sex.

Even straight men have man crush's and same for females.

Sat, 25 Sep 2010 13:13:38 UTC | #524701

ddeniska's Avatar Comment 86 by ddeniska

I think this is a situation where they simplest explanation is probably the correct one: homosexuality contradicts evolutionary theory. And instead of putting forth all these ridiculous hypotheses about gay uncles and sneaky males, we should be looking in far more plausible locations. My own feeling is that it is primarily a psychological condition developed in early childhood. The reason this topic is important is because of the travesty that is the psychological profession: its governing bodies have forbidden research and treatment that deviates from the idea of homosexuality being innate.

Mon, 31 Jan 2011 07:58:10 UTC | #586209

DavidMcC's Avatar Comment 87 by DavidMcC

Ddeniska, it has been established that hormone levels in you're mother's womb during your gestation have the major effect on your likely sexual orientation. This would not "contradict evolutionary theory", because it isn't heritable. Wiki article

"A 2010 endocrinology study by Garcia-Falgueras and Swaab[2] says that intrauterine exposure to hormones is largely determinative."

Mon, 31 Jan 2011 13:38:12 UTC | #586276

opposablethumbs's Avatar Comment 88 by opposablethumbs

Comment 86 by ddeniska My own feeling is that it is primarily a psychological condition developed in early childhood.

But what about the widely documented incidence of homosexuality in non-human animals? Do e.g. ducklings, baby chimps, elephant calves and penguin chicks develop a comparable psychological condition?

Mon, 31 Jan 2011 14:19:01 UTC | #586289

ccw95005's Avatar Comment 89 by ccw95005

This is a fascinating issue that I've thought about a lot. No question that homosexuality, especially exclusive homosexuality, decreases the likelihood that one's genes will go forward into future generations and therefore logic suggests that it should be selected out rather quickly by evolution. But it hasn't, and in fact there's a lot of homosexuality in other primates and as far as I know in other animals as well. We can think up all sorts of explanations for the advantages of homosexuality to human survival and reproduction but most of them feel like you're trying desperately for an answer and not succeeding.

Therefore I suspect that the answer is that homosexuality isn't really genetic in origin. And obviously it isn't a matter of choice - no one can choose what turns him or her on. So what's left is stuff that happens in the womb. I suppose we should also consider what happens in the first few years of life but that sounds unlikely to me.

What I suspect is that sexual desire is a tricky thing for genetics to arrange precisely. Remember that we all start out unisex and develop into males and females according to the hormones that we are bathed in as fetuses. And once the sex is chosen, our carnal desires also have to be worked out, somehow, in our brains. How does evolution produce such instinctive desires in the developing neurons? It must be devilishly tricky, and since presumably the penis or uterus develops at a different time from the implantation of sexual preference in the brain, it may be that alterations in the hormones between the two - or something else that happens in the womb - may explain why there's a disconnect.

None of that, of course, means that there's anything unnatural about homosexuality. We're all different in one way or another.

Now if someone does discover a gene for homosexuality, and further research bears that out, my theory goes out the window.

Mon, 31 Jan 2011 19:56:35 UTC | #586427

Steve Zara's Avatar Comment 90 by Steve Zara

Therefore I suspect that the answer is that homosexuality isn't really genetic in origin.

Why not? Sexuality in humans is quite different from that in some other apes, and what is different but genes?

There is no need to struggle with the idea of purely gay genes - the idea is pretty clearly nonsense, as they would not be passed on.

But sexuality need not work like that at all, and the explanation could be very simple. We all have gay genes. By that I mean that we all have genes that can result in offspring being homosexual. But not always! How would these genes work? It could be that the female body has a memory of how many children it has produced. The more children, the more certain hormones are produced during the development of a fetus, the more likely the fetus is to develop into a gay child.

Why do this? Such gay genes would have to help with their own survival, and they would: having some later children non-breeding could be a good way to help the survival of the offspring of earlier children. It doesn't mean that the later children have to act as good uncles or aunts (although they might), just having extra members of the family to hunt and gather food without having their own children to feed could be enough. So, families in which the mother had "gay child producing" genes would survive better.

I'm not saying that this is correct, but I propose it as a simple and workable explanation for why a certain proportion of the human population is homosexual, and how it would work genetically.

There is no need to consider homosexuality contrary to evolution, or some mistake of development. It could be something selected for. Indeed, it's such a consistent aspect of human societies, I think that's very likely.

Mon, 31 Jan 2011 20:07:05 UTC | #586428