homosexuality and evolution

Hey all

There was an article in a populair psychology magazine here about homosexuality and evolution. That made me thinking.. if we take the following facts as true (for the sake of the following discussion):

1) homosexuality is something you're born with
2) homosexuals probably don't procreate as much as heterosexuals
3) in evolution, only genes with a certain function seem to survive (survival of the fittest on dna level)

so.. if these are true.. how come that the number of homosexuals isn't drastically declining? It must mean that they are of some kind of use to society, from an evolutionary viewpoint.. in the article a theory was that although gays don't have kids of their own, they help taking care of their brothers/sisters kids, so the family genes (which include the 'gay-gene') gets preserved and carried on to the next generations.

My question to you is.. what do you think of this? From a evolution point of view, homosexuals must have be of great 'use' in society, otherwise the specific gen wouldn't have survived since the dawn of menkind... what could, according to you, that use be?

NB: I really really hope I didn't offend someone with the above.. if so, please let me know so I can try to explain myself better!

 

it's a good point.. "black swans of Australia will also form sexually active male-male mated pairs and steal nests or form temporary threesomes with females to obtain eggs" once they have got the eggs they kick the female to the kerb, the two males are more successfull at rearing chicks and this preserves the gay gene.. incidently the two males will mate for life, cool!

 

This is why I tend to focus on the "nurture" theory as oppoed to the "nature" theory. It makes a little more sense to me that one's sexuality is somewhat learned through life experiences. I don't know for sure, but Velvet's post does make me think. I'd love to read that article, but it's probably in Dutch, isn't it?

 

yeah.. the article's in Dutch (with nice pictures of humping male lions and stuff *grin*).. although the other poster in this thread gave an example that's almost exactly the same as the one in the article.. so maybe he knows an english version?


If you're interested in the nature/nurture discussion I could copy and article on that from an english psychology study book and send it to ya.. I'd have to check how many pages it is though.. they explore the different theories (and to spoil the end: the conclusion is that there's no hard evidence that there's one truth..). It's pretty interesting.. let me know.

 

PLEASE send me that article from the English psych book. I'm very interested in this topic and would really like to know more.

 

Well a theory I had is that the homosexual gene has survived for all these years ironically enough because of suppression and prejudice. If you think about it was impossible in previous centauries to have an openly gay lifestyle and up until a few decades ago it was frowned upon for a woman to be unmarried at a certain age. Due to this homosexual people entered into 'normal' relationships and had children therefore passing on the gene to future generations. Had it always been acceptable for homosexuals to be in relationships then the gene may have died out naturally because in past centauries artificial insemination and surrogate mothers did not exist as they now do. Homosexuality may well be useful in stopping the planet becoming too overpopulated. If you think of the trouble over-crowding is causing in Japan and then think that they only legalised Homosexuality in the mid ninety’s, it does make some sort of sense. Some people search for psychological reasons for homosexuality but as a lesbian myself and knowing this is not the case, I do believe that the cause must lye in genetics. Of course it is just my theory but in a way I’m quite happy no one has conclusively proven the cause lies in genetics because then with the whole designer baby thing people could screen for the gene and eventually phase it out

 

perhaps the gay gene was evolved to bring down our population numbers which are growing at an exponential rate probably...

but i also agree with monosphere, that it would make more sense for people to sordove pick up on sexuality through life experience...

 

But are you suggesting that I have 'learned' to be gay through something that has happened in my life? And in the same respect have straight people 'learned' to be straight? If it was a learned experience I think we would all be straight and not have to worry about being outcasts from our friends and families, bullied at school, discriminated against in the workplace and told we will all burn in hell by random people with a bible. If by 'learned' you mean learned who we are and arent attracted to, who we really are and what our natural sexual orientation is, then yes i would agree with you.

 

well i guess it can mean alotta different things for alotta different people... maybe a traumatizing experience, maybe theyve just always gotten along with the opposite sex better and thought they made better 'buds'... you learn to love it i guess...

 

Well I haven’t had a traumatising experience and I have an equal amount of male and female friends (with mixed orientation) and I think both sexes make equally good friends. So your theory doesn’t really make sense to me. If sexuality was learned then we would all be straight as that is what society teaches.

 

why would you say your gay then?, just curious

 

i agree with mono that its more of a nurture thing and not something im born with... im think its more on how you look at life and how comofortable you are with things and how often you CONTEMPLATE things in your head..

i think we all have the ability to become bisexual, its all just how we look at it and deal w/ it.

evolution is such a long process, that we would not bea ble to see any drastic declination in population of a certain gene.. (which imo, homosexuality is not some gene, or dna mutation)

 

Hm.. evolution is a never ending process, but mutation can come and go very quickly.. so changes can occur very quick.. so therefor if homosexuality is nature based, it most be of some use. I like the explanation a previous poster gave about how being 'in the closet' made sure the genetic information was passed on..

 

Well because it's the truth in that I don’t find men sexually attractive and I find women extremely sexually attractive. :H

 

i think we all have the ability to become bisexual, its all just how we look at it and deal w/ it.

Only bisexual people ever say that.

Genetic mutations happen constantly and can be a subtle as eye colour or as extreme as deformity.

 

People,

It is important to note a few things about evolution before undertaking this kind of discussion.

Evolution is caused by gene mutation. A mutation has the connotation of being bad (and it usually is) but can sometimes be helpful. The certain species of fish could have an individual that grew up with a mutated gene, giving it scales that are more slippery- providing it the ability to move faster through the water. However, the scales could have just have easily ended up less slippery, larger, more visible, more brittle or any number of negative attributes. If a fish is born with more brittle scales it will die more easily, or its kids will, or their kids. Eventually it will be taken out. The fish with the more slippery scales will be better & have better/more kids who each do better. This new slightly different species takes over. Thus we have evolution.

Gene mutations are very infrequent.

Humans are no longer evolving. Humans stopped evolving when we started becoming more civilized- with one male and one female having a few kids each. There was no longer an Alpha male. The bad gene mutations are no longer being taken out. We are actually devolving, but luckily that takes a long time too. We will never notice any changes as time goes on. Advances in technology (ex. health care) will make far more of a difference than human devolution.

So

Although homosexuality will help the problem of overpopulation, there is no reason for us to believe that overpopulation is the reason it exists.

This also kills Casey's theory that homosexuality was carried on by society's unacceptance.

There is a reason for homosexuality. And it has absolutely nothing to do with the last several thousand years of human existence. We know that gay people are less likely to have kids than straight people so we can all imagine that the gay genes would be filtered out- but they have not been. Therefore, having some gay people mixed in the tribe helps the species out. I don't know how. DistantState's article on Black Swans of Australia is a wonderful example of a possibility.


Feel free to ask questions.
My name is Jon, I’m 19, I'm gay, and I go to the University of Cincinnati - Engineering College.

 

It seems evolution has played a big part in our sexuality. Women are generally bisexual, since sleeping with other women doesn't reduce the number of babies they produce. Men on the other hand are generally a lot more straight, and repulsed by other men, this is to make sure they impregnate as many women as possible.

I think evolution clearly affects our sexuality. So the question remains: why are some people homosexual?

 

People,

It is important to note a few things about evolution before undertaking this kind of discussion.

Evolution is caused by gene mutation. A mutation has the connotation of being bad (and it usually is) but can sometimes be helpful. The certain species of fish could have an individual that grew up with a mutated gene, giving it scales that are more slippery- providing it the ability to move faster through the water. However, the scales could have just have easily ended up less slippery, larger, more visible, more brittle or any number of negative attributes. If a fish is born with more brittle scales it will die more easily, or its kids will, or their kids. Eventually it will be taken out. The fish with the more slippery scales will be better & have better/more kids who each do better. This new slightly different species takes over. Thus we have evolution.

But we aren’t talking about gene mutations that effect physical attributes. The mutations in question are more behaviour orientated i.e. they affect the brain rather than outward appearance. In comparison to the complex nature of the human body fish have a simplistic biological make up and so it’s impossible to accurately use fish as a comparison.



"Male homosexuality is not caused by low levels of testosterone, but may follow lower levels of prenatal testosterone following stress to the mother, affecting brain development. There are genetic predisposing factors, the survival of which might result from bisexuality conferring some reproductive advantage."


And why wouldn't social suppression have an affect on the gene when it’s a clear factor in passing the gene on? To claim it had no effect is to also claim that no homosexual person has ever reproduced in order to fit into society.

The purpose of the fish anology was to explain how evolution works. It works the same way for physical changes as it does with changes in the brain (which is still a physical change). And there is no reason the fish anology does not work. A faster fish and a faster human will have more & better kids than a slower fish and slower human. A smarter fish as well as a smarter human will have more & better kids than a less intelligent fish and a less intelligent human.

{Quote}
I agree. That doesn't negate anything I said.

Yes, you are correct in saying that the gene has been carried on, or at least assisted by homosexual people in straight relationships because of society. However, the question at hand is, "Why is the gene here," and not, "Why is the gene still here."


Gene mutations are very infrequent.

No they aren't.

Dictionary definition: Mutation: A change or modification; the process of changing.


A mutation happens every time reproduction occurs and covers everything from hair colour to serious conditions.

While perhaps I should not have had "very" in there, they are still infrequent. I appreciate you using outside quotes, but they aren't helping you at all. Why is that dictionary definition there?
I'm hesitant to give you that gene mutations necessairly happen every time reproduction occurs. Support for that one would be helpful, but also explain why it is significant either way.


Humans are no longer evolving. Humans stopped evolving when we started becoming more civilized- with one male and one female having a few kids each. There was no longer an Alpha male. The bad gene mutations are no longer being taken out. We are actually devolving, but luckily that takes a long time too. We will never notice any changes as time goes on. Advances in technology (ex. health care) will make far more of a difference than human devolution.

We are constantly evolving and changing and the reason we don’t notice is due to the fact that normal subtle gene mutations are overlooked as a natural selection process. In regards to technology. I agree it will have much more of a noticeable effect but what you have overlooked is that this is due to evolution in intellectual terms which again effects the brain function. A person can actually still evolve after birth a prime example is when in disability, for example in blindness a person other senses will become more active to compensate for the sense that has been lost.

No we're not. Sorry. The natural selection process stopped a long time ago, like I said. The bad gene mutations are no longer being taken out, and the good gene mutations do not help the individual have a bigger & better family.

You are STRONGLY confusing development with evolution. That might be the basis for your misunderstanding.




The rest has been chopped off and put in a second post because hipforums said it is getting too long.

 

This is the continuation of the previous post.

So

Although homosexuality will help the problem of overpopulation, there is no reason for us to believe that overpopulation is the reason it exists.

Your saying yourself that it will help overpopulation. We should consider it as a reason for its existence because the most obvious reason is usually the right one and because it would make sense that such a widely spread mutation would serve some purpose. Also you haven’t offered any other explanation for its existence so that we are able to evaluate which theory is more plausible.


This last paragraph is based on two falacies.

The first is the following:

Cum hoc ergo propter hoc
This fallacy is similar to post hoc ergo propter hoc. The fallacy is to assert that because two events occur together, they must be causally related. It's a fallacy because it ignores other factors that may be the cause(s) of the events.

"Literacy rates have steadily declined since the advent of television. Clearly television viewing impedes learning."





​

This fallacy is a special case of the more general non causa pro causa.



[end]

I'll give you that one too because they are related, and both apply.

Non causa pro causa
The fallacy of Non Causa Pro Causa occurs when something is identified as the cause of an event, but it has not actually been shown to be the cause. For example:

"I took an aspirin and prayed to God, and my headache disappeared. So God cured me of the headache."





​

This is known as a false cause fallacy. Two specific forms of non causa pro causa fallacy are the cum hoc ergo propter hoc and post hoc ergo propter hoc fallacies.



[end]

This is all in regard to your, and a few other people's idea that overpopulation is the reason homosexulaity exists. You said that your reason was "because it would make sense that such a widely spread mutation would serve some purpose" which we have both agreed on. You have yet to provide support.


The second falacy is the following:


Argumentum ad ignorantiam

Argumentum ad ignorantiam means "argument from ignorance." The fallacy occurs when it's argued that something must be true, simply because it hasn't been proved false. Or, equivalently, when it is argued that something must be false because it hasn't been proved true.
(Note that this isn't the same as assuming something is false until it has been proved true. In law, for example, you're generally assumed innocent until proven guilty.)

Here are a couple of examples:

"Of course the Bible is true. Nobody can prove otherwise."



"Of course telepathy and other psychic phenomena do not exist. Nobody has shown any proof that they are real."


​

[end]


I didn't post a theory on here because I do not have one. I stated this later on in the last three sentences of my first post.





This also kills Casey's theory that homosexuality was carried on by society's unacceptance.

But as you havent offered any other reason for its exsistant or a thoery to back up why you disagree with mine i dont see how this is the case. I havent denied that bisexuality is also a factor in carrying on the gene i am merly saying that gay people have been reproducing in hetrosexual relationships for a long time which has surely helped to pass on the genetics.


Woops, I meant that homosexuality was not caused by society's unacceptance.
Sorry.
Keep in mind, however, that the reason homosexuality has lasted the relatively short time of several thousand years, is not what we are arguing about.

There is a reason for homosexuality. And it has absolutely nothing to do with the last several thousand years of human existence. We know that gay people are less likely to have kids than straight people so we can all imagine that the gay genes would be filtered out- but they have not been. Therefore, having some gay people mixed in the tribe helps the species out. I don't know how. DistantState's article on Black Swans of Australia is a wonderful example of a possibility.


Why has it nothing to do with the last several thousand years of human existence? Everything has to do with our past.


Wo.. It has nothing to do with the last several thousand years of human existence because we stopped evolving several thousand years ago, as detailed above.