Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
homosexuality and evolution
-
22-08-2009 4:16amHi guys,
I just raised an issue on another thread and it got me thinking. So i just wanna put it out there and see what others think.
Do you think you are born gay or is it a choice/lifestyle?
If we are born gay, where does it fit in regarding evolution? Why did we evolve to be non-procreating in an existence which is doomed without it? Theories i have read include: we have evolved to be gay to reduce competition for suitable mates....ie survival of the fittest (darwinian theory). Indeed if this is right, it is doing a good job. If it is true 10% are gay, then that means about 500 million people in the world are gay in 2009...or 250 million procreating couples (assuming both are fertile and 50% male and female demographics). If 250 million families have 2 kids, that is 500 million more people for competition every 20 or 30 years...if u extrapolte that over the centuries (past and future)...that would leave our popultaion at a much much much higher number than it is now, or would be in say, 1000 years. So then, are gays saving the world from extinction by overpopulation and depletion of resources?
Maybe we are gay so that we can practice sex with other males (or females) so that we are good at it when the suitable member of the opposite sex comes along. I heard that particular theory on a documentary on homosexuality in other species. But if this were true, then wouldnt all lads be doing lads until they get married, and same with girls? Or Maybe they would if society told them it was ok. In certain countries in the world, it is widespread practice for adolescent boys to engage in sexual activity with their male friends, and when they mature, to marry off and "become" straight.
Anyway, just a few thoughts. Id like to hear some of your views, especially from scientists, philosophers and academics, although all comments appreciated.
Also, please keep your homophobic, religious, or bigotted views to yourself. Serious, open minded, scientific, intelligent posts only
ThanksTagged:0
Comments
-
I think you misunderstand evolution.
Evolution is about what is best for the individual, not the group. It has no plan for the future or for what is best for the population. It is only concerned with that is best for the "selfish genes". Since the expressions of genes are what are selected by natural selection.
It is difficult to see any evolutionary direct advantage to homosexuality. Not producing offspring effectively ends your genetic line. It may be that homosexuality is a somewhat deleterious mutation, one that due to the evolution of humans as social creatures with a strong psychological desire to reproduce is not selected out. (Most gay couples would love to have kids just as much as everyone else)
Since we now live in a society where the cruelty of natural selection is no longer a significant force in our day to day lives, mutations that otherwise would have not survived can now propagate.
There are many examples of homosexuality in the wild, and also in zoos, perhaps there are some clues here as to what environmental conditions favour such traits.0 -
thanks for your input 5uspect. i do understand evolution and i understand mutations and evolution are tools we use to combat problems face in the present environment, to overcome them and ensure survival. I was just putting forward some points i had recently read. I just dont know where homosexuality fits into all this. One thing is for sure,homosexuality has been around for millions of years. Dolphins display homosexuality by one male inserting his penis into another males blowhole (funny word given the context). Modern dolphins are about 50 million years old and homosexuality has been seen across 250 different species. Why has homosexuality been conserved for so long over so many different species? We have evolved and morphed incedibly over the last 50 million years, yet homosexuality has remained constant. homosexuality seems to be as old as the urge to procreate. The only other genes that have been conserved for so long are basic house keeping biomolecules, the genes of which are almost identical in the oldest life form, bacteria, and the newest, humans. These molecules are essential for life and so have been conserved for so long, but why has homosexuality been conserved for so long. What is its purpose?0
-
Read something about this before .
People traditionally lived in groups or tribes. If an infant was born then both parents were the natural protectors of the child (as well as the other members of the tribe to a lesser extent). In theory every member of the adult population could procreate. However if an adult didnt procreate they could likely play a bigger part in raising/protecting the children of their siblings (sisters children first obviously cause you may not be related to your brothers children).
So basically a gay aunt/uncle was more useful to a given individual child than a straight aunt/uncle whos primary concern was their own children.
Cant remember where I read this, dont know if it stands up to the scrutiny of evolutionary biologists?0 -
MRI's in recent years have shown that there's quite distinct differences in straight and gay, male and female brains — with gay male's brains developing more like straight females and lesbian's developing somewhat like straight males. Link
I don't believe that there's a 'gay gene' or a particular defect that alone determines sexuality because if there was it would inevitabley be removed by natural selection. Having said that however, I'm now going to contradict myself and say that I do believe it's genetic — but the genes that cause it are not doing so directly but instead, causing it indirectly without ‘intent’. (I'll explain in a minute.)
I've read plenty about the gene theory and also about the prenatal hormone-exposure theory.The hormone-exposure theory alone I don't believe feasable because if a child's sexuality was determined by his mother's hormone levels while he developes in the womb, there wouldn't be such similar patterns and common trends amongst homosexuals around the world; as found by countless surveys. (Trends would indicate that homosexuality is genetic.)
What I've yet to read about are any ideas of how the two theories; -the gene theory and hormone-exposure;- could work if combined. If, instead of there being a 'gay gene', there were particular genes which caused a child to inherit a particular sensitivity in the brain to certain hormones, hormones associated predominantly with either male or female brain development, it would account not only for the common patterns found amongst homosexuals all over the world, but also it would explain why gay men's brains are developing somewhat like women's and lesbian's brains like men's. It would explain why Dean Hamer found that gay men had more gay male uncles and cousins on the maternal side of the family than on the paternal side. It would also explain why homosexuality has never been eradicated by Darwinian evolution. While a 'gay gene' or a mutation would certainly be eliminated, genes causing a brain to develop like a female's would never be removed; those genes would be absolutely necessary for the survival of the species.
It would actually explain an awful lot of things..
(I posted this into both of your threads because it seems that different people are following different parts of the forum.)0 -
MRI's in recent years have shown that there's quite distinct differences in straight and gay, male and female brains — with gay male's brains developing more like straight females and lesbian's developing somewhat like straight males. Link
I don't believe that there's a 'gay gene' or a particular defect that alone determines sexuality because if there was it would inevitabley be removed by natural selection. Having said that however, I'm now going to contradict myself and say that I do believe it's genetic — but the genes that cause it are not doing so directly but instead, causing it indirectly without ‘intent’. (I'll explain in a minute.)
I've read plenty about the gene theory and also about the prenatal hormone-exposure theory.The hormone-exposure theory alone I don't believe feasable because if a child's sexuality was determined by his mother's hormone levels while he developes in the womb, there wouldn't be such similar patterns and common trends amongst homosexuals around the world; as found by countless surveys. (Trends would indicate that homosexuality is genetic.)
What I've yet to read about are any ideas of how the two theories; -the gene theory and hormone-exposure;- could work if combined. If, instead of there being a 'gay gene', there were particular genes which caused a child to inherit a particular sensitivity in the brain to certain hormones, hormones associated predominantly with either male or female brain development, it would account not only for the common patterns found amongst homosexuals all over the world, but also it would explain why gay men's brains are developing somewhat like women's and lesbian's brains like men's. It would explain why Dean Hamer found that gay men had more gay male uncles and cousins on the maternal side of the family than on the paternal side. It would also explain why homosexuality has never been eradicated by Darwinian evolution. While a 'gay gene' or a mutation would certainly be eliminated, genes causing a brain to develop like a female's would never be removed; those genes would be absolutely necessary for the survival of the species.
It would actually explain an awful lot of things..
(I posted this into both of your threads because it seems that different people are following different parts of the forum.)
did u actually read that link you posted?
This is what is says:
They found a significant difference in INAH3 (the part of the brain they tested) size between heterosexual men and women. The INAH3 size of the homosexual men was apparently smaller than that of the heterosexual men and larger than that of the heterosexual women, though neither difference quite reached statistical significance.[30]
Byne and colleagues also weighed and counted numbers of neurons in INAH3, tests not carried out by LeVay. The results for INAH3 weight were similar to those for INAH3 size; that is, the INAH3 weight for the heterosexual male brains was significantly larger than for the heterosexual female brains, while the results for the gay male group were between those of the other two groups but not quite significantly different from either. The neuron count also found a male-female difference in INAH3, but found no trend related to sexual orientation.[30]
Basically, there is a significant difference in the regions of this part of the brain from man to woman. Compared to straight males, the gay males part is somewhat smaller and compared to the straight woman, is somewhat bigger but nothing significant.
Id hardly call that "quite distinct diffferences"0 -
Advertisement
-
dubcitycentre wrote: »did u actually read that link you posted?
This is what is says:
They found a significant difference in INAH3 (the part of the brain they tested) size between heterosexual men and women. The INAH3 size of the homosexual men was apparently smaller than that of the heterosexual men and larger than that of the heterosexual women, though neither difference quite reached statistical significance.[30]
Byne and colleagues also weighed and counted numbers of neurons in INAH3, tests not carried out by LeVay. The results for INAH3 weight were similar to those for INAH3 size; that is, the INAH3 weight for the heterosexual male brains was significantly larger than for the heterosexual female brains, while the results for the gay male group were between those of the other two groups but not quite significantly different from either. The neuron count also found a male-female difference in INAH3, but found no trend related to sexual orientation.[30]
Basically, there is a significant difference in the regions of this part of the brain from man to woman. Compared to straight males, the gay males part is somewhat smaller and compared to the straight woman, is somewhat bigger but nothing significant.
Id hardly call that "quite distinct diffferences"
It seems Trance did read the Wikipedia link (*cringe*) because reference 48 is a bbc article that is based on this 2008 article (which I hope can be accessed), which states in its introductionHeterosexual Males and Homosexual Women showed a rightward
cerebral asymmetry, whereas volumes of the cerebral hemispheres
were symmetrical in Homosexual Males and Heterosexual Women.
This study was done using MRI scans of living patients. The INAH3 article you reference used autopsy material for viewing under a microscope.
So there are significant physical differences between gay/straight men/women's brains, but maybe no significant differences in the particular area of the brain INAH3.0 -
dubcitycenter wrote:did u actually read that link you posted?
Yeah I did, did you?- Gay men and straight women have, on average, larger right brain hemishperes. Gay women and straight men have, on average, larger left brain hemispheres.
- The average size of the INAH-3 in the brains of gay men is approximately the same size as INAH 3 in women, which is significantly smaller, and the cells more densely packed, than in heterosexual men's brains.
- The anterior commissure is larger in women than men and was reported to be larger in gay men than in non-gay men.
- Gay men's brains respond differently to fluoxetine, a selective serotonin reuptake inhibitor.
- The functioning of the inner ear and the central auditory system in lesbians and bisexual women are more like the functional properties found in men than in non-gay women (the researchers argued this finding was consistent with the prenatal hormonal theory of sexual orientation).
- The startle response (eyeblink following a loud sound) is similarly masculinized in lesbians and bisexual women.
- Three regions of the brain (medial prefrontal cortex, left hippocampus, and right amygdala) are more active in gay men than non-gay men when exposed to sexually arousing material.
- Gay and non-gay people's brains respond differently to two human sex pheromones.
- Gay men and lesbians are significantly more likely to be left-handed or ambidextrous than are non-gay men and women.
"MarvintheFish wrote:It seems Trance did read the Wikipedia link (*cringe*)
I've read all of the referenced links and more published papers that aren't associated with the wikipedia article. I only quote wikipedia because it summarizes all of the information well and is more convenient than posting a million different links.0 -
Yeah I did, did you?
- Gay men and straight women have, on average, larger right brain hemishperes. Gay women and straight men have, on average, larger left brain hemispheres.
- The average size of the INAH-3 in the brains of gay men is approximately the same size as INAH 3 in women, which is significantly smaller, and the cells more densely packed, than in heterosexual men's brains.
- The anterior commissure is larger in women than men and was reported to be larger in gay men than in non-gay men.
- Gay men's brains respond differently to fluoxetine, a selective serotonin reuptake inhibitor.
- The functioning of the inner ear and the central auditory system in lesbians and bisexual women are more like the functional properties found in men than in non-gay women (the researchers argued this finding was consistent with the prenatal hormonal theory of sexual orientation).
- The startle response (eyeblink following a loud sound) is similarly masculinized in lesbians and bisexual women.
- Three regions of the brain (medial prefrontal cortex, left hippocampus, and right amygdala) are more active in gay men than non-gay men when exposed to sexually arousing material.
- Gay and non-gay people's brains respond differently to two human sex pheromones.
- Gay men and lesbians are significantly more likely to be left-handed or ambidextrous than are non-gay men and women.
I've read all of the referenced links and more published papers that aren't associated with the wikipedia article. I only quote wikipedia because it summarizes all of the information well and is more convenient than posting a million different links.
I read most of it but surely its up to you to make sure the link is sound before posting. To be honest i got put off when i read the part of the article about the INAH3. In the paragraph it says there is no significant difference and then later, as in the 2nd bullet point you posted above, it contradicts that and say there are significant differences. Its just not a relaible link...but thats Wikipedia for u. Not ur fault0 -
Evolution is about what is best for the individual, not the group. It has no plan for the future or for what is best for the population. It is only concerned with that is best for the "selfish genes". Since the expressions of genes are what are selected by natural selection.
It is difficult to see any evolutionary direct advantage to homosexuality. Not producing offspring effectively ends your genetic line.
Difficult, yes, but not impossible. It just requires a small change in your thinking. It seems you have done your homework and know a good bit more than the layman on this topic, but we could go a little further on it together here.
For example you are MOSTLY right when you say Evolution is not about the group, but group selection theory does have a lot to say for it. The fact is evolution and selection is about the group sometimes, and about the individual some other times.
However, predominently it is about neither of these. It is about the gene. The gene is the unit of selection in most cases, not the group OR the individual. With this small change in thinking we suddenly realise it is not as difficult as you think to see the benefit of homosexuality.
You share much of your genes with siblings. Not all, clearly, but much. Not all genes are "active" either. So if you are gay and your siblings are not then there is still a very good chance that they carry the gene (or to be more exact but it is off topic - the group of genes and factors) that cause homosexuality.
Therefore a gene does not die, as you suggest by suggesting non-reproduction "effectively ends your genetic line". To negate your statement all we would need is for the "Active" host to provide some selective advantage to the off spring of its siblings.
This we can see easily as in any species if 4 siblings each had 1 child they devote 100% parental time to each child. If however 3 have one child, and one is a "roaming carer" between the others, we have 133% parental time.
All the gene "Wants" is to get into the next generation successfully. This does not require that the host it is "Active" in is the one that reproduces.
This theory is supported by predictions too. It would make sense that we would find signs that the gene is "activated" somehow and preferably when the "active" host has siblings to take care of children for. This is because we clearly do not want a one child family to have a gay child, so we push to make this happen less often than not.
This is in fact what we see. The hormones thought to activate the gay gene increase in the mother with each successive male child she has, which increases the likelyhood of a homosexual child with each birth. This means the gay individual will have older siblings which are closer to child bearing age than him/her thus increasing the chance there will be a next generation to care for, and will be cared for by this additional younger, fitter "roaming parent".
So not only do these genes therefore support their own reproduction, they appear to have adapted quite well to expressing themselves at just the right time to ensure there is likely a cause for them to be there. The more children you have, the more a "roaming parent" would be beneficial, therefore the increasing likelyhood of a gay individual the bigger the family gets makes much sense. Think of it like nature "Calling in the cavalry"
So three cheers for these, "natures carers", who knows how important they were in the primacy of our species, we may have more to thank them for than we know. Remember that gratitude when next faced with a morally devoid cretin who wants to beat them down in some way or other.0 -
Great post nozz.
Though let's not forget that a gay man is perfectly capable of siring a child while actually devoting his true affections elsewhere.
Oscar Wilde had a wife, after all.
In older, less monogamously inclined societies it may not have been strange for a person to have had a wife, a girlfriend and two boyfriends. The majority of the history for homo sapiens was as a hunter gatherer society. I can imagine that being bonded romantically to your fellow hunters while away from the tribe for a week or two could be quite beneficial to group cohesion. Not to mention that they'd probably go home to their wives afterwards, of course.0 -
Advertisement
-
This is a popular science forum; discussion of homosexuality is to be based on science alone. There are to be no comments about the morals of homosexuality.
Use the report post button if you see something objectionable.
/sets about tidying thread.0 -
Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 92,173 Mod ✭✭✭✭Join Date:Posts: 90411
One theory I've heard is that sisters of gay men are more fertile and so will more than make up for any reduction in the number of children from the brother.
A selfish gene doesn't care about individuals.
The genes for cystic fibrosis don't sound like they would survive either. The disease means you get a short life expectancy and most males infertile and yet 1 in 19 Irish people carry this gene. It would almost certainly have meant that where both parents were carriers 1 in 4 of the children would be unlikely to have offspring themselves. But overall it the gene protects carriers from some diseases.0 -
My opinion is that being homosexual is quite simply a genetic defect. Please don't take that as an insult...i'm simply talking about at the genetic level. Clearly we've evolved to mate with the opposite sex but as like everything in evolution there is a trend from genetic perfection to genetic imperfection. Just like some people are born genetically blind, genetically predisposed to breast cancer, physically strong, physically weak, despite the effects on our survival, so some men are born genetically more feminine (which includes the extreme of being gay) and some women are born genetically more masculine (which includes the extreme of being a lesbian).
There are two reasons for this. One is simply that natural selection is not perfect; there are always exceptions in every species, where genes for blindness, being gay, etc. survive for a period of time and there will always be some exceptions out of 6 billion people (mutations are happening all the time). Sometimes dormant genes weeded out by natural selection thousands of years earlier suddenly re-appear despite no history in the immediate family (general comment, not talking about genes for homosexuality). The point is that no human is a perfect, intelligent, strong, handsome, straight, reproducing machine! We vary in every way, including sexuality from a strong likelihood of our genes surviving to a weak likelihood. I'm not saying homosexuality is a weakness in general, just from a reproduction point of view. (unless you accept the group selection theories)
The second reason, and the reason homosexuality is more common than other "genetic exceptions" is quite simple. Homosexuality was suppressed by human culture for perhaps thousands of years and still is today in many parts of the world. Homosexuals have, historically, had no choice but to enter into straight relationships, have children, etc...indeed they may be more successful than hetrosexuals in that respect......and indeed, many homosexuals, due to religion or culture, may have denied the truth to themselves. Thus, natural selection never acted and the gene(s) remained in the gene pool and spread.
Indeed if the widespread acceptance of homosexuality spread everywhere in the world, (as I hope it does), it may, ironically, lead it to be weeded out by natural selection towards a tiny minority. Then again, there is IVF treatment and surrogate mothers and surrogate fathers, and if homosexuals are allowed legally to have kids, the genes for it could easily survive.
This is all just my theory, makes sense to me anyway.0 -
Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 92,173 Mod ✭✭✭✭Join Date:Posts: 90411
A Primal Nut wrote: »Homosexuals have, historically, had no choice but to enter into straight relationships, have children, etc...indeed they may be more successful than hetrosexuals in that respect......and indeed, many homosexuals, due to religion or culture, may have denied the truth to themselves. Thus, natural selection never acted and the gene(s) remained in the gene pool and spread.
among many cultures in the past homosexuality wasn't frowned upon
most cultures had a piresthood / monkhood to soak up surplus breeding stock to keep the population down
in roman times a man would spend many years in the legion before being able to afford a family
the high mortality rate in childbirth meant that powerful men had many wives until the 1850's and longer elsewhere
here until recently the average marriage age for males was 37
apart from a short time of Victorian values in the west and Islam in the east, it was easy enough for a man not to spend his life with a woman even if there was social pressure to do so, which there wasn't in most cases.0 -
Primal,
I think the problem with your post is that you have assumed that reproduction is somehow the “right” way and that therefore a gene or collection of genes which prevent it in SOME individuals is somehow “defective”.
A quick look around the animal kingdom shows this not to be the case however. Many creatures, most notably hive type creatures (ants in the insect world, mole rats in the mammal world for two examples) have dedicated non reproducing elements. Their species is far from weakened by this, but in fact strengthened by these elements.
It is not a leap to suggest homosexuality is in fact the same thing in humans. They are just the non reproducing element (in many cases, but as we have seen not always due to surrogacy etc). of our species and I think we can be similarly strengthened by them as indicated in my longer post above.
Our species engage in sexual activity for pleasure however, unlike many animals who do it for hormonal reasons (like when the females are “in heat” and give off special pheromones to excite the males).
In such animals the non reproducing element is maintained by merely switching off those genes designed to respond to the females in such a way. This does not work in Humans however. It is again not a leap to suggest that homosexual behaviour would therefore be the equivalent of diverting or curtailing the reproductive urge in humans.
In short, there is no harm caused by these non-reproducing elements in a species, and much good that can come from them. I therefore do not see, as you do, these genetic elements as a “defect”.0 -
Capt'n Midnight wrote: »might make sense if weren't for the many other options available
among many cultures in the past homosexuality wasn't frowned upon
most cultures had a piresthood / monkhood to soak up surplus breeding stock to keep the population down
in roman times a man would spend many years in the legion before being able to afford a family
the high mortality rate in childbirth meant that powerful men had many wives until the 1850's and longer elsewhere
here until recently the average marriage age for males was 37
apart from a short time of Victorian values in the west and Islam in the east, it was easy enough for a man not to spend his life with a woman even if there was social pressure to do so, which there wasn't in most cases.
This thread has really set me thinking.
I think the answer why the homosexual condition has not been "bred out" by natural selection in the past 5 million years (since we separated from chimps), is because the survival of the human race has been helped by homosexuals.
For nearly 99% of the time since we separated from chimps, we have been cave man hunter gatherers
Homosexuals in caveman- hunter gatherer societies would have come in very handy and would have helped the survival of the group
For starters, he wouldnt want to copulate with the partner of straight males in the group. This would help social harmony.
He could hunt, and would be more prone to sharing his his food with everyone. His energy would be given for the benefit of the group. He would look after kids much better than a straight guy, and he would be less likely to die in battle with another tribe (because he would be less likely to fight).
I know there is a stereotype vibe in comments, but it's self evident to me that homosexual men are less selfish, more caring, less aggressive, more dedicated to group activities than straight men.
In a caveman society, these qualities would have helped tribes to flourish and multiply.
I guess its a bit like a colony of bees ( I dont know the precise details), but aren't most bees sterile , worker bees), they dont procreate, but they do help the survival of the species)0 -
Yes LouisC, the non reproducing elements in species that have them can be seen clearly to be a strength of that species, not a hindrance of it. This is not just in bees (and most other hive type insect colonies) but also in hive type mammals like the bald mole rat and more.0
-
dubcitycentre wrote: »Dolphins display homosexuality by one male inserting his penis into another males blowhole (funny word given the context).
I had a super lol when I read this part. Childish I know.0 -
He would look after kids much better than a straight guy,
he would be less likely to die in battle with another tribe (because he would be less likely to fight).
I know there is a stereotype vibe in comments, but it's self evident to me that homosexual men are less selfish, more caring, less aggressive, more dedicated to group activities than straight men.
How you can actually present this idea as a legitimate explanation when you have those ridiculous stereotypes as the rudiments of your argument?0 -
How you can actually present this idea as a legitimate explanation when you have those ridiculous stereotypes as the rudiments of your argument?For starters, he wouldnt want to copulate with the partner of straight males in the group. This would help social harmony.He could hunt, and would be more prone to sharing his his food with everyone.He would look after kids much better than a straight guyand he would be less likely to die in battle with another tribe (because he would be less likely to fight).I know there is a stereotype vibe in comments, but it's self evident to me that homosexual men are less selfish, more caring, less aggressive, more dedicated to group activities than straight men.
In a caveman society, these qualities would have helped tribes to flourish and multiply.
Now, we've covered the role of the homosexual male in these societies and the possible reasons why it is evolutionarily advantageous but what about homosexual women? Why is it advantageous to have homosexual women in these societies?nozzferrahhtoo wrote: »Yes LouisC, the non reproducing elements in species that have them can be seen clearly to be a strength of that species, not a hindrance of it. This is not just in bees (and most other hive type insect colonies) but also in hive type mammals like the bald mole rat and more.
This thread really is a mix of sociology, anthropology and biology...socioanthrobiology anyone?0 -
Advertisement
-
Now, we've covered the role of the homosexual male in these societies and the possible reasons why it is evolutionarily advantageous but what about homosexual women? Why is it advantageous to have homosexual women in these societies?
I could give two different answer to this one.
Firstly, I would say "For the same reasons as I have previously given for males". The non-reproducing elements of species strengthen that species in and of themselves. There is no criteria therefore to suggest that such elements have to be a certain sex. In fact, quite the opposite. By virtue of the fact they are a non-reproducing element, their sex becomes instantly irrelevant to the discussion.
Secondly however, even if you were able to argue that the non-reproducing elements are only useful if male... this would then become a "Why to men have nipples" type question. In evolution certain traits are present in both sexes as evolution never weeded them out of the sex where they are superfluous.
The reasons for this are twofold. One is that evolution is a mindless process and it does not say "Oh wait, I do not need this bit here so I will get rid of that". Secondly it is much more complicated to have two separate blue prints for males and females than it is to have one overall blue print with logic like "IF female and IF certain hormone is present SWITCH this section of code on". In other words all the code for developing breasts and producing milk from them lies in every male, it just lies unused. In fact the code for developing a tail is in all of us too, it just remains unused.
So the answer, as over-simplified as it sounds, to "Why do men have nipples?" is "Because women have them".
Similarly, even if you could argue that homosexuality only made sense in males of our species, the presence of the code in females to switch it on would merely be explained the same way.
To repeat the same point, but to do it better than I just did, I quote from another persons articles:Why do men have nipples? Because women need them. Both men and women have the same set of genes (more or less), and follow very similar developmental pathways, and the nipple represents a developmental constraint or byproduct: mutations that knock out the male nipple might also knock out the female nipple, so the structure is retained in both sexes. Male nipples are a byproduct of a function needed by the other sex.0 -
Excellent, well constructed answer...if I was a teacher I'd give it an A+
Seriously well answered because even if the females had no beneficial role as 'mates' for the males and did not add extra brawn to the troop/pack, the coding that is hardwired into the genetic code appears anyway regardless of sex and is present even before the sex of the unborn is decided.0 -
I need to correct you on one small thing if you do not mind. Don’t hate me
The sex of the unborn is decided from the very point the sperm meets the egg. There is no point after or before that where the sex is decided. It is literally decided by which sperm gets there first and whether it is a type X or type Y sperm. So there is no "before the sex of the unborn is decided". Once there is an unborn present, it's sex is decided.
Remember that when you start hearing pregnant women telling each other things like “Oh if you want a boy eat more Potatoes” or some such old wives tale. Trust me, I have heard a LOT of them. I have never had the heart to correct them though0 -
nozzferrahhtoo wrote: »I need to correct you on one small thing if you do not mind. Don’t hate me
The sex of the unborn is decided from the very point the sperm meets the egg.
Therefore, before our sex is even decided (in the context of the benefits of male versus female homosexuality in a society), the genes are there, waiting for expression and the sex of the individual does not matter.0 -
Yea I was afraid maybe I had misunderstood you, but I went ahead regardless as it is not an unuseful thing to have posted on a thread like this. However apologies are in order that I decided to do that at the possible mistake of it being at your expense. Sorry.
Actually as an extent of the “Why do men have nipples” point, one could also apply this to homosexuality directly, and not just to your question of why women would be gay.
We might also ask, why do some men love other men? The answer is possibly because women need to love men. If there are vectors of code required to make women be attracted to men, then similarly to the code for nipples this code is present in both sexes. We have mechanisms to modulate which path the code takes and how and when they are expressed.
This constitutes a separate, but complementary, answer to the one I gave before on the topic of this thread and is more an explanation of how homosexuality may have arose in the first place, whereas what I have been saying so far in the thread is more to do with, having arisen, why evolution would select for it.0 -
Not sure about this. The Alpha male in pack societies is the one who mates with the females and also the one who decides who eats and how much they get to eat. Alpha males would tolerate homosexual males because they don't attempt to copulate with females but the act of 'sharing' by the homosexual male may be nothing to do with selflessness and more to do with subservience to the alpha/lead males and dominance of the Alpha male.
Rather than looking after the kids, I feel he would be less likely to kill offspring from a rival male as they are not a 'future' threat to his dominance.
I think you're jumping to some massive conclusions there. Just because early humans lived in groups doesn't mean we were like wolves. Not all "pack socieites" are the same.
First of all, due to the dramatic increase in lenght of childhood (needed for intelligence) and the increased vunreability of young children (we needed to be born earlier so our big heads could fit out our mothers vaginas) monogamy arose. One parent was no longer enough to take the strain of child-rearing.
The alpha male would not have mated with all the females, instead he would have mated with the best one (you can't be in love with two people at the same time). This "everyone's a winner" approach led to massively, insanely increased cooperation (how humans have achieved all this amazing stuff in our short histroy?). Cheating would have been a lot rarer than it is today, merely because any woman caught cheating would have the absolute shite kicked out of her and would have lost all social status within the group. Bear in mind it was monogamy that held these groups together so well (evolutionary basis for the whole "slut" thing?).
As i said before, males within these groups (especially those who had already secured a mate) would have been highly co-operative. There's just no way men would have killed children in their own group. If one tried to take more than his fair share the others would confront him over it and he would lose due to strenght in numbers (chimps are not intelligent enough to think like this).
Obviously social status still existed and some people held more sway than others. But like today, it would have been much more of a social slope than a hierarchy.stereotypes and anecdotal evidence aside, it's obvious that homosexual males have always played a contributory part in society and if it is a genetic trait then evolution has held onto it for a reason.
Now, we've covered the role of the homosexual male in these societies and the possible reasons why it is evolutionarily advantageous but what about homosexual women? Why is it advantageous to have homosexual women in these societies?
See, that is whopping big if right there. Even if there is some genetic basis for homosexuality it's very unlikely to be the whole story. I really don't think sexuality is as fixed as the mainstream media like to say it is (strangely enough, most science articles i've read on the issue seem to be on the button). I'm not saying homosexuality is a choice, just that environmental factors such as social position / acceptance from the other members of one's gender, surely play a massive role in determining sexuality.
As for brain differences, the brain changes as we grow up depending on how we use it. If a male spends his childhood doing female activities and assimilating himself with the females of the group then it seems obvious to me that his brain would share some simmilarities with a female brain.0 -
I think you're jumping to some massive conclusions there. Just because early humans lived in groups doesn't mean we were like wolves. Not all "pack socieites" are the same.
I don't think there are any correct answers to be found here.
First of all, due to the dramatic increase in lenght of childhood (needed for intelligence) and the increased vunreability of young children (we needed to be born earlier so our big heads could fit out our mothers vaginas) monogamy arose. One parent was no longer enough to take the strain of child-rearing.When did monogamy arise in humans? I'm interested in that because I know that in certain Polynesian tribal societies even in the 1700's, sex was seen as recreation and enjoyed by men and women with no emphasis on monogamy. Child-rearing in some of those tribes was performed by the women as a group activity while the men taught the younger boys how to fish, sail and fight.
The alpha male would not have mated with all the females, instead he would have mated with the best one (you can't be in love with two people at the same time). This "everyone's a winner" approach led to massively, insanely increased cooperation (how humans have achieved all this amazing stuff in our short histroy?). Cheating would have been a lot rarer than it is today, merely because any woman caught cheating would have the absolute shite kicked out of her and would have lost all social status within the group.Bear in mind it was monogamy that held these groups together so well (evolutionary basis for the whole "slut" thing?).As i said before, males within these groups (especially those who had already secured a mate) would have been highly co-operative. There's just no way men would have killed children in their own group. If one tried to take more than his fair share the others would confront him over it and he would lose due to strenght in numbers (chimps are not intelligent enough to think like this).
Obviously social status still existed and some people held more sway than others. But like today, it would have been much more of a social slope than a hierarchy.See, that is whopping big if right there. Even if there is some genetic basis for homosexuality it's very unlikely to be the whole story.I never said it wasA huge amount of our genetics is based on environmental factors.
I really don't think sexuality is as fixed as the mainstream media like to say it is (strangely enough, most science articles i've read on the issue seem to be on the button).I'm not saying homosexuality is a choice, just that environmental factors such as social position / acceptance from the other members of one's gender, surely play a massive role in determining sexuality.0 -
Now there's another sweeping generalisation right there
When did monogamy arise in humans? I'm interested in that because I know that in certain Polynesian tribal societies even in the 1700's, sex was seen as recreation and enjoyed by men and women with no emphasis on monogamy. Child-rearing in some of those tribes was performed by the women as a group activity while the men taught the younger boys how to fish, sail and fight.
Judging by "sex was seen for recreation" I'd assume this polygamy was socially constructed and also possibly overplayed by european explorers.
Many free love communes were set up in the 60s and subsequently collapsed as people fell in love and got jealous of the other members of their gender for having sex with "their" partner. This + my own experience would lead me to believe that humans are genetically preprogammed towards monogamy.
Unless you are suggesting that some people/groups of people somehow lack the neccesary genes and are incapable of falling in love.....0 -
Judging by "sex was seen for recreation" I'd assume this polygamy was socially constructed and also possibly overplayed by european explorers.
Many free love communes were set up in the 60s and subsequently collapsed as people fell in love and got jealous of the other members of their gender for having sex with "their" partner. This + my own experience would lead me to believe that humans are genetically preprogammed towards monogamy.
It has been suggested in the past that sexually transmitted infections are the real reason for the encouragement of monogamy in many societies. A society weakened by sexual diseases was vulnerable to attack.
I would suggest however that your own experience has been shaped by the social constructs that you were brought up in.Unless you are suggesting that some people/groups of people somehow lack the neccesary genes and are incapable of falling in love.....
No, not suggesting that at all.0 -
Advertisement
-
I would question any standpoint based on the assumption that humans can not love more than one person at a time. There are many examples, in relationships and outside them of this very thing occurring. Even outside the realm of relationships we see parents loving all their children and not just one of them. In relationships we see cultures with Polygamy where one partner loves all the others very powerfully. I myself do not love those lost to me any less now simply because I love another more than I can describe.
In fact I would be wary of standing in front of someone who lost a partner to death or separation and try to convince them that because they have been lucky enough to find and love another, that they do not love the former any more. Their displeasure at the accusation is likely not to be shared vocally, but more physically.
In fact, in a world of dwindling resources, it appears the human capability to feel love is possibly the only resource which appears not to be finite. We may love each person in our lives DIFFERENTLY, but this does not make our love for them any less real or mutually exclusive.0
Advertisement