What Exactly Is Bi-Sexuality !!!

quote:

Originally posted by Earwicker:
Think about heritability. (The extent to which a trait is heritable - i.e. genetic rather than due to the environment - nature rather than nurture. A heritability factor of 1 = entirely genetic.) If you have a gene that causes you to "prefer" (excuse the euphemism!!) men over women, then you will not pass on that gene to progeny, because (as of last time I picked up a copy of the new scientist...! ) a man shagging another man up the bum don't produce no sprogs. So the "gay" gene is a deadend on the phylogenetic tree.

I think you'll find that genetics is a little more complex than that and that there may indeed be good evolutionary reasons for the existence of a 'gay gene'. Some recent research certainly points in that direction, notably that carried out by the University of Padova, Italy:

How homosexuality is 'inherited'

"Gay Genes" May Increase Fertility

Regards
Steve M

Earwicker,

quote:

Think about heritability. (The extent to which a trait is heritable - i.e. genetic rather than due to the environment - nature rather than nurture. A heritability factor of 1 = entirely genetic.) If you have a gene that causes you to "prefer" (excuse the euphemism!!) men over women, then you will not pass on that gene to progeny,

I wouldn't want facts to get in the way of your argument, but I feel compelled to point out that the current thinking on the nature–nuture debate is that this dichotomy is misleading at best, false at worst. Genes and the environment interact in complex ways (the environment in which genes find themselves has a bearing on their expression), so simple arguments about the heritability (or not) of behaviours is often riddled with flaws.

quote:

I'm a qualified scientist...

Presumably not in evolutionary biology.

Joe

7V

quote:

I think you'll find that genetics is a little more complex than that

Absolutely!

Earwicker's argument makes the common mistake of assuming genetic expression is an either/or phenomenon. Within genetics there exists the property of 'penetrance' ie the persistence or effectiveness of a gene. Consider the gene for Huntington's Disease. It has two alleles (varieties). One is a very rare allele that will causes the person to fall victim to the disease. The other, much more common, variety prevents the disease. This particular gene is 100% penetrant. If you were born with the allele that causes the disease, then you are absolutely certain to develop Huntingdon's later in life. The penetrance of the gene which causes Type 1 (early onset) diabetes is only 30% penetrant and acquring diabetes for those with the gene is influenced by other factors e.g environment.

If there is a gay gene (or genes) it might be similarly penetrant to the diabetes gene (a terrible word in this context I grant you!). Many men and women may carry the gene but due to environmental phenomena (e.g hormonal balance in the womb) do not express it in their behaviour i.e they are heterosexual. Similarly, others may have the gene and it is triggered by stimuli that results in them developing as non-heterosexual.

Whatever the actual reason for non-heterosexual behaviour might be, the real question we should be asking is 'Do we care'? Gay, lesbian and bisexual people do no harm to the gene pool and some would argue they actually have beneficial effects.

What is destructive is the aggressive, ignorant, and judgmental way religion and politics uses the subject to create 'evil' 'degenerates' and 'sin' in order to gain control and influence.

Why can't people just be tolerant of one another and not see difference as a threat!

D

quote:

Why can't people just be tolerant of one another and not see difference as a threat!

Too easy!

Unfortunately tolerance is a recessive human gene. Intolerance is even more marked in childhood and youth. If adults weren't around to keep some control over their behaviour kids would annihilate each other in one or two generations. It would take them even less time to annihilate the adults, given half a chance.

Nime

Nime,

How old are the intolerant and murderous children of whom you speak? I'm trying to understand whether they're born evil or acquire it and, if so, when?

Regards
Steve M

I was quoting a fascinating hour-long radio interview with a danish academic who has specialised in the study of the parallels between bullying and genocide.

The human being and children in particular have a built-in recognition of variation from the norm. It can be the most trivial trigger but once the "victim" responds (usually with signs of fear) they are identified and selected as targets for aggression.

Morals and respect for others rights are totally ignored by kids who would otherwise be thought of as "well-adjusted" and "as good as gold".

They will physically and psychologically torture their victim and rob them of their dinner money without a qualm. They take great pleasure from the victim's suffering and many simply do not question what they are doing. (The progamme was frequently punctuated by bullies talking about their exploits)

The academic then went on to discuss genocide and the similar behavioural patterns involved.
The de-humanising of the intended victims as worthy of consideration. The desire to destroy their victims becomes overwhelming. Propoganda quickly becomes an artform as rumour, fear and hate take over all rational thought.

It is too obvious to mention the "persecution" throughout history of jews, blacks, idiots, lepers, christians, RC, Protestants, witches, white-collar workers, blue-collar workers, men and women, terrorists, bikers, homosexuals, etc.etc.

Meanwhile, back at the ranch:

In Cambodia many children reported their parents to the authorities. These children cannot possibly have been ignorant of the awful consequences of their own actions.

The author of "The Lord of the Flies" was probably thinking along rather similar lines to those so clumsily-expressed above.

Nime

Well thnaks everybody, now I've learnt lots about that, maybe we should now concentrate designing a horse with our next commitee meeting, innit ?


Fritz Von Namely a Camel

quote:

Originally posted by 7V:
Nime,

How old are the intolerant and murderous children of whom you speak? I'm trying to understand whether they're born evil or acquire it and, if so, when?

Regards
Steve M

Isn't this the old "nature vs nurture" argument?

quote:

Originally posted by Dougunn:
Absolutely!

Earwicker's argument makes the common mistake of assuming genetic expression is an either/or phenomenon.
D

No it bloody doesn't. And I took my degree in biology.

100% genetic = heritability factor of 1, a heritability of 0.5 means that half the trait is genetic, half the trait is due to environment. Genetics lesson one: phenotype = genotype + environment. Noddy and Big Ears.

Steve, I have read these arguments before - I'd love to see a PROPER explanation of how a gene that causes one to have unproductive ("gay") copulations can proliferate.

It is an anecdotal observation that gay men are unusually "randy", and going back to the story of the necrophilic ducks, I suppose if you just fuck ANYTHING then there is a good statistical chance one of your couplings will be successful... provided you include a few young females in your porkethon. So I suppose the "I will fuck anything" gene that might cause you to shag other men as well as women might have a statistical advantage... but then if you compare the chance that gene has over one that causes you to shag ONLY women, you'll see that that gene has an obvious advantage.

Don't argue unless you know what you're talking about.

EW

quote:

Originally posted by Dougunn:
Earwicker

If I understand you correctly you are proposing that only heterosexual sex is 'natural' since any other type would be phylogenetically pointless?

What, exactly, are the 'genetic aberrations' you ignore?

D

It would be pointoless in that it doesn't produce progeny. At the risk of stating the obvious, the point of sex is to reproduce. (And provide an opportunity to shuffle the genes as opposed to asexual reproduction which doesn't - and doesn't give evolution much to work on.)

By aberrations, I mean that many deleterious traits are due to genetic faults that have their origins at the point of conception - or even previously. Many genetic diseases are therefore not necessarily heritable (i.e. it's just a bit of damaged DNA). If there is a gay gene, it may be an aberration (a genetic disorder).

EW

quote:

Originally posted by Nime:
It is too obvious to mention the "persecution" throughout history of jews, blacks, idiots, lepers, christians, RC, Protestants, witches, white-collar workers, blue-collar workers, men and women, terrorists, bikers, homosexuals, etc.etc.

Can anyone spot the odd one out?

Regards
Steve M

quote:

Originally posted by Earwicker:
No it bloody doesn't. And I took my degree in biology.

...

...Don't argue unless you know what you're talking about.

No further comment required really.

Regards
Steve M

"I'd love to see a PROPER explanation of how a gene that causes one to have unproductive ("gay") copulations can proliferate."

Alturistic sibling/grouping effects. So your genes are more likely to survive if your progeny has more sibling/group members who will devote resources to caring for your genes in another person wihtout competeing for females.

"a man shagging another man up the bum don't produce no sprogs"

The redundant inclusion of phrses like "up the bum" are, in my expeerience, frequently accociated with an unhealthy interest in anal sex that is almost exclusively hetrosexual and frequently homophobic.

Matthew

quote:

Originally posted by Gianluigi Mazzorana:
Too easy!

Gianluigi - One moment you write like an Italian learning English, and then you come out with correct English spelling that 50%+ people here get wrong!! That should cut down the odds of who you actually are.

As far as I can make out, homosexuality happens in nature in a percentage of the population and therefore must be natural . Why does it matter anyway? It doesn't alter anything.
One thing that does concern me and make me feel uncomfortable about some (most) of the gays that I know, is that some tend to be slightly racist. That sounds like a massive generalisation and I don't mean it that way, it's just something I've noticed about the people I know, and I am not aware of any racists amongst any other of my friends. I'm sure this isn't normally the case, and I'm wondering whether to post this to be honest. Frankly they wouldn't be my friends if they were, and that raises the question why I can be friends with racist gays. I don't know the answer to that. I'll have to think about it. Hopefully you can all tell me that this is a fluke.

Hmmm

I think racism takes many forms, some subtle, some obvious, but I don't see any connection with bi-sexuality, gay sexuality, heterosexuality, or 'in the closet, not sure what I want' sexuality...

And then I suppose it comes down to how sensitive one is about certain comments, and the cultural perspective.

For instance, being in Australia, and this being a forum predominately populated/frequented by UK members, I often find the term in reference to HiFi equipment 'made in the far east' or of 'far eastern manufacture' to somehow be aligned with negative or derogatory connotations, seemingly perhaps, of an racist but certainly negatively descriminatory nature... to ME, but I wouldn't argue that is racist per se, just that coming from my part of the world, it seems that way.

Could you expand on how your friends seem racist?

Best

John... :-)

quote:

Originally posted by Johns Naim:
..but I don't see any connection with bi-sexuality, gay sexuality, heterosexuality,...

Me neither. It seems odd to me.
One guy that comes from a large Italian family is very right-wing in many areas, thinks Thatcher was the greatest leader we ever had, and he and his partner are bigoted and racist. He in particular does it all in a jokey way, which is his general manner anyway, but it's there nonetheless.
Another is an Architect and part time piano bar crooner. Very similar profile. They don't know each other.
Another that I always see shopping is much quieter in manner, but is ever so slightly racist by being timid and suspicious.
Another that I used to work with and bump into sometimes, is exactly the opposite and has very similar views to myself (thank God!).
Another, very outrageous gay guy, very camp, and a great laugh, but racist in a sort of "Oh no, we don't really want to go there, do we.." sort of way.
I fail to see any connection with racism and sexuality and am baffled too, altough it seems to be those that are more outwardly gay, rather than those who just are without being camp. Hmmm...that's it I think!
(The more I think of it, I discover that I know a huge number of gay men somehow).

quote:

Originally posted by 7V:

quote:

Originally posted by Earwicker:
No it bloody doesn't. And I took my degree in biology.

...

...Don't argue unless you know what you're talking about.

No further comment required really.

Regards
Steve M

Further comment invited nonetheless!

quote:

Originally posted by Gianluigi Mazzorana:

quote:

Why can't people just be tolerant of one another and not see difference as a threat!

Too easy!

Who mentioned threats?

Population genetics quiz for Earwicker

Got a quiz for ya... Sometimes the measured heritability of a trait is very low -- less than 0.10 -- and yet the trait is under almost complete genetic control, not environmental. How can this be?

Joe

quote:

Originally posted by matthewr:
"I'd love to see a PROPER explanation of how a gene that causes one to have unproductive ("gay") copulations can proliferate."

Alturistic sibling/grouping effects. So your genes are more likely to survive if your progeny has more sibling/group members who will devote resources to caring for your genes in another person wihtout competeing for females.

"a man shagging another man up the bum don't produce no sprogs"

The redundant inclusion of phrses like "up the bum" are, in my expeerience, frequently accociated with an unhealthy interest in anal sex that is almost exclusively hetrosexual and frequently homophobic.

Matthew

Hmm. Yes, I hinted at the altruism effect earlier.

You're sort of right, but what statistical chance does a gene have if it (by its own nature) reduces its prospects of being passed on to progeny? (By causing the carrier to prefer homosexual couplings.)

What you say about nurturing immature offspring is of course true, but one has to have some progeny to nurture in the first place... which requires the possessor of the genes to have a successful heterosexual copulation.

As for your point about anal sex, not my bag but each to his own. I think you're romanticising rather.

EW

quote:

Originally posted by Joe Petrik:
Population genetics quiz for Earwicker

Got a quiz for ya... Sometimes the measured heritability of a trait is very low -- less than 0.10 -- and yet the trait is under almost complete genetic control, not environmental. How can this be?

Joe

Probably because it's a common one-off mutation. Can you give an example?

Many awful genetic diseases are the result of chromosomes fracturing around "fragile sites" i.e. sites where there are an abundance of weak adenine-to-thiamine bonds. Although not necessarily "heritable" per se, they are entirely genetic effects, and may appear slightly heritable due to the similarities between the parent and offspring chromosome supermolecules.

In a nutshell, one-off molecular effects present an entirely genetic effect (i.e. the environment doesn't put its own two-penneth in) but it's not necessarily going to be a heritable trait.

EW

Earwicker,

quote:

Probably because it's a common one-off mutation. Can you give an example?

Your earlier description of heritability -- "100% genetic = heritability factor of 1, a heritability of 0.5 means that half the trait is genetic, half the trait is due to environment" -- implies that as heritability approaches zero, the trait being examined has a smaller and smaller genetic component and a larger and larger environmental component. That can be true, but a curious (and predicted) empirical finding is that many life-history traits dealing with reproduction, as well as many metabolic processes under strict genetic control, have low heritability -- scores less than 0.10.

To solve the puzzle you have to understand what heritability is and what it is not. Heritability, in the broad sense, is the proportion of total diversity expressed in a given trait at the population level that's caused by genetic variability. But if the gene controlling the trait shows little variation in the population -- in other words, if the gene differs little or at all from one person to the next, as many genes that control essential survival and reproductive processes do -- then the genetic variation in the population of that gene is near zero. You plug the numbers into the equation and viola -- a low heritability score emerges, despite the trait being largely if not entirely determined by genes, not the environment.

The other thing implicit about heritability is that measuring it is entirely context dependent. Heritability of a trait in one environment can be (and often is) completely different from the heritability of the same trait in different environment. Throw in some of the latest thinking that the nature-nurture dichotomy is false anyway, (see Matt Ridley's book "Nature Via Nurture: Genes, Experience and What Makes Us Human") and it's easy to see why naively interpreting heritability scores is fraught with problems -- all the more so when people start quoting the heritability of, say, IQ or sexual orientation.

My point was not so much to throw a population genetics question in your direction as to show that an incomplete or flawed understanding of evolution can be problematic, not least because it has led to all sorts of actual and proposed societal nastiness over the decades.

Earlier, you were backing up your claim by playing the authority card -- I studied this is university; I know, etc. I'm just saying that perhaps you don't know the subject as well as you think you do. Well, that and your eugenics thread had me a bit worried. (I'm also concerned about kids begetting kids, by the way, but that's why I'm a proponent of sexual education and ready access to contraception.)

Joe

quote:

Originally posted by Joe Petrik:
Earwicker,

Your earlier description of heritability -- "100% genetic = heritability factor of 1, a heritability of 0.5 means that half the trait is genetic, half the trait is due to environment" -- implies that as heritability approaches zero, the trait being examined has a smaller and smaller genetic component and a larger and larger environmental component. That can be true, but a curious (and predicted) empirical finding is that many life-history traits dealing with reproduction, as well as many metabolic processes under strict genetic control, have low heritability -- scores less than 0.10.

To solve the puzzle you have to understand what heritability is and what it is not. Heritability, in the broad sense, is the proportion of total diversity expressed in a given trait at the population level that's caused by genetic variability. But if the gene controlling the trait shows little variation in the population -- in other words, if the gene differs little or at all from one person to the next, as many genes that control essential survival and reproductive processes do -- then the genetic variation in the population of that gene is near zero. You plug the numbers into the equation and viola -- a low heritability score emerges, despite the trait being largely if not entirely determined by genes, not the environment.
Joe

I suspect you're confusing the heritability co-efficient with the Hardy-Weinberg equilibrium.

Example. Genetics (i.e. the heritable bit of the equation) may confer upon grass the potential to grow to 2 m hight; it reality it may only grow to 1 m, due to nutrient availability etc. The hight of grass may have a heritability, therefore, of approx 0.6 - the genes are 60 % responsible for the ultimate height, the environment 40 %.

When you talk of variability in gene frequencies, we're on to a whole new subject. If the frequency of a gene in a population is the same from one generation to the next, then it is in equilibrium (H-W) and natural selection is not acting on it; if the Hardy-Weiberg equilibrium is disturbed, and the frequency of a gene is changing from generation to generation, then evolution is taking place. You are SELECTING a gene, because it has a positive survival differential (or co-efficient, if you like).

This is the concept of gentic fitness: it's simply the statistical chance that a gene will be passed on to viable progeny.

EW

I bet one of those kids on the streets of Stoke told you all that perfectly possible theoretical gobbledygook ?

Fritz Von I didn't know most species are becoming (if not already) sterile ?