Wednesday, October 2, 2019

Is this the Gay Germ?



Poster for 1997 World AIDS Day (Wikicommons - Neil Curtis, Christian Michelides). Antiretroviral therapy has reduced infections in AIDS victims, but the decline hasn't been the same for all pathogens. Some infections have shown modest declines or no change at all. Could they be due to the "gay germ"?



Male homosexuality has low to moderate heritability (30 to 45%). A recent study in the UK Biobank and 23andMe has identified a number of genetic variants associated with same-sex sexual behavior. Together, they account for 8 to 25% of variation in male and female same-sex behavior (Ganna et al. 2019). There is thus a genetic predisposition, but it's weak and may simply reflect a smaller population of neurons for heterosexual orientation.

So this genetic predisposition seems to be interacting with something in the environment. But what?

There may be different environmental factors. One possibility would be a pathogen that alters its host's sexual orientation in order to enhance its chances of spreading to other hosts. This is Greg Cochran's "gay germ" theory (Cochran et al. 2000).

With the introduction of antiretroviral therapy for AIDS, we may have a chance to identify candidates for the "gay germ." Over time this therapy should reduce the incidence of infections in AIDS victims. Indeed it has, but the decline has been uneven.  A retrospective study of AIDS autopsies in Vienna between 1984 and 1999 found a lower rate of decline for infections due to fungi and most bacteria than for infections due to protozoa, viruses, and mycobacteria:

Extracerebral protozoal (Pneumocystis carinii, toxoplasmosis), Mycobacterium avium complex, viral [e.g., cytomegalovirus (CMV)], multiple opportunistic organ and CNS infections, and Kaposi sarcoma significantly decreased over time. There was less decrease in fungal infections, while bacterial organ and CNS infections (except for mycobacteriosis), lymphomas, HIV-associated CNS lesions (around 30%), non HIV-associated changes (vascular, metabolic, etc.) and negative CNS findings (10-11%) remained unchanged. (Jellinger et al. 2000)

These findings are in line with those of a retrospective study of AIDS autopsies in San Diego between 1982 and 1998:

Pneumocystis carinii pneumonia and Mycobacterium avium complex decreased, whereas bacterial infections increased and the frequency of fungal infection remained unchanged over time. (Eliezer et al. 2000)

After the lungs, such pathogens most often target the brain:

This study suggests that despite the beneficial effects of antiretroviral and anti-opportunistic infection therapy, involvement of the brain by HIV continues to be a frequent autopsy finding. (Eliezer et al. 2000).


Similar to a recent autopsy study from San Diego, these data suggest that despite the beneficial effects of modern antiretroviral combination therapy, involvement of the brain in AIDS subjects continues to be a frequent autopsy finding. (Jellinger et al. 2000)

Subjects with brain alterations at an early stage otherwise seemed almost normal:

Of the cases with early brain alterations, systemic opportunistic infections were present in only 5.9% of the cases, neoplasms in 0.5%, and neoplasms and opportunistic infections in 1.7%. (Eliezer et al. 2000)


A few caveats

The change in incidence over time partly reflects differences between fast-developing infections and slow-developing ones. By definition, people succumb more quickly to the former than to the latter. When antiretroviral therapy was still unavailable those infections were the ones that generally killed people with AIDS. Better control of aggressive infections may have also created a better environment for the growth of less aggressive infections.


But ...

It is harder to explain why the brain should remain a major pathogenic target. It is especially hard to explain why subjects with brain alterations at an early stage otherwise seemed almost normal.

Eggers et al. (2017) pointed out another apparent contradiction: HIV-associated neurocognitive disorders (HAND) are continuing to develop in people whose HIV infection is under control.

Despite the brain infection taking place in the days after primary infection, the development of HAND takes years. As an explanation for this ostensible contradiction, it has been suggested that initially, the brain infection is relatively well controlled, while later, there is a quantitative and qualitative breakdown of immune control in the CNS (Eggers et al. 2017)

Some authors have suggested co-infection by the Hepatitis C virus, but Eggers et al. (2017) ruled this out:

While some authors implicated HCV co-infection in the pathogenesis of HAND, a recent large and well-controlled study found no evidence for worse cognitive function in HCV co-infected patients, at least in the absence of liver dysfunction. (Eggers et al. 2017)


Pathogen "X"

Could we be looking at an unknown pathogen that exists independently of HIV? Over the years some have suggested that HIV is not the only pathogen involved in AIDS. In this case, pathogen "X" may cause adverse effects that get blamed on HIV, but its relationship with HIV is incidental, the only common denominator being the gay lifestyle.

I would propose the following scenario. Pathogen "X" enters its host early in life, just in time to alter that person's psychosexual development. From then on it remains in the background and reaps whatever benefit it gets from its behavior manipulation. Past the age of 40 the host becomes less useful, and the pathogen begins to cause more adverse effects, including neurocognitive disorders that are wrongly attributed to HIV.

Pathogen "X" is most likely a fungus. If we go back to the two retrospective studies, the fungal infections were the ones that seemed the least influenced by the introduction of antiretroviral therapy.


References

Cochran, G.M., Ewald, P.W., and Cochran, K.D. (2000). Infectious causation of disease: an evolutionary perspective. Perspectives in Biology and Medicine 43: 406-448.
https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.182.5521&rep=rep1&type=pdf 

Eggers, C., G. Arendt, K. Hahn, K., I.W. Husstedt, M. Mashke, et al. (2017). HIV-1-associated neurocognitive disorder: epidemiology, pathogenesis, diagnosis, and treatment. Journal of Neurology 264: 1715-1727
https://link.springer.com/article/10.1007/s00415-017-8503-2

Eliezer, M., R.M. DeTeresa, M.E. Mallory, and L.A. Hansen. (2000). Changes in pathological findings at autopsy in AIDS cases for the last 15 years. AIDS 14(1): 69-74.
https://journals.lww.com/aidsonline/Fulltext/2000/01070/HIV_associated_brain_pathology_in_the_United.8.aspx

Ganna, A., K.J.H. Verweij, M.C. Nivard, R. Maier, R. Weddow, et al. (2019). Large-scale GWAS reveals insights into the genetic architecture of same-sex sexual behavior. Science 365(6456)
https://science.sciencemag.org/content/365/6456/eaat7693 

Jellinger, K.A., U. Setinek, M. Drlicek, G. Böhm, A. Steurer, and F. Lintner. (2000). Neuropathology and general autopsy findings in AIDS during the last 15 years. Acta Neuropathologica 100(2): 213-220.
https://www.ncbi.nlm.nih.gov/pubmed/10963370

44 comments:

Santo said...

Two reasons why conserfs like you and Coch want to spread this theory

- first: homophobia
- second: incapacity to fully understand natural selection..

First of all, humans evolved to be capable to differentiate sex from procreation. To control sex impulse as well to use it in recreational related-activities. It's mean non-reproductive sex desire seems to be in-selection among humans, too. Broader is the sexual behavior spectrum, more diverse it will be;

Secondly, sexuality is correlated with cognition and personality. Humans evolved to be psychologically and cognitively diverse because it's better have different specialist types to solve different problems. So it's expected a mix among so-called masculine and so-called feminine traits, and it's also mean about sexual desire. A matter of probability;

Thirdly, only very strong and specifically-defined natural selection can ''clean'' population's related phenotypes from ''debris'' as homossexuality.

There are some anecdotal evidence of more common bissexual behavior among heterossexual african-descent men... R-strategy or huge fertility to attacks environmental challenges also mean trends to higher phenotypical variation or hyper-sexuality maybe;

Fortly, your evidences sound very weak, like a incident correlation... only way to prove it it's finding direct association between fungus and behavior. Like, in the exact way, a homossexual guy feel sexual desire to another male, so-called ''germ'' manifest in the brain. Also, what i already said in Pumpkin Person blog. If you find some microorganisms, unusual ones, in healthy homossexual male sperm, so, this theory also possibly will have some breath.

Fifhtly [whatever]: you know we have the similar number of bacterias and cells, right*

I don't believe if there is a ''gay germ'' will not have a ''sexual germ''.

That's the problem about science without philosophy, i mean, not verborragic crap lots of white thinkers had produced, and i'm including many ''non-liberals''. Scientists put their personal biases over ethics.

To fully understand homossexuality we must understand all sexuality. Why not try to understand the biological origins about heterossexual behavior**

Still about heritability. Autism seems pretty heritability and some people also believe it's a kind of ''brain infection''. Higher or lower heritability may mean less than we bet. And all the time people is confusing heritability with inheritance levels, what's matter for selective processes.

How explain one of the identical twin pairs with no ''fungus/pathogen/germ infection''*

Sean said...

"I would propose the following scenario. Pathogen "X" enters its host early in life, just in time to alter that person's psychosexual development." Difficult to see how that might happen non-sexually. And yet whatever went on on the past, there are very few societies outside Melanesia where boys are sexually violated at puberty. A non-sexual vector for the gay bug causing a behavioural change and making men want sex with men, with nothing in it for the bug? After frem being implicated in heart disease, cancer and diabetes, the gum disease bug apparently gets into the brain, where is produces enzymes that destroy brain cell and eventually give you Alzheimer's. Does it do that to stop you brushing your teeth and kiss. Maybe it does. The gum disease bug uses the body's own immune inflammation, which ceases to be ever completely turned off once you get to middle age. I have heard of some rare types of premature Alzheimer's that knock out sexual inhibitions.

The problem as I see it for the bug hypothesis is, assuming the bug is sexually transmitted, the infected one (the totally gay man) is spreading the bug to the up-until-that-point uninfected by managing to have homosexual contact with young males disinterested in having sex with other men until after they have had sex with one! It isn't common enough for pubescent boys to have sexual contact with older males pressed on them for such a hypothesis to be tenable

Bonobos are gayish and less heavily built than chimps. On average, gay men look different to straight men in the same sort of direction(more weakly built) bonobos look different to chimps. My opinion is certain genetic factors create the predisposition to be gay and while there may be a bug that encourages such behaviour and makes it compulsive, that is not the main reason why there are gay men. Or why since the time of Cro Magnons human males seem to be getting gayer looking https://youtu.be/awilQhCSyaA?t=802. T

Santo said...

Human beings is a highly phenotypical-combinatory species. We are complex specially about our intelligence.

I read somewhere fungus is more resistant or spend more time to disappear from organism...

Al Smith said...

I am fond of this theory because it appeals to the imagination, while also having a certain logic.

But I wonder if the SNPs from GWAS would not have a clearer immunogenic association, if it were a germ. That there would be
riskier HLA groups or perhaps genes affecting the blood-brain barrier.

Or might the association be masked, if it infected the mother? Her immune system or even behavior being the key factor? But wouldn't that mean a higher concordance between twins?

Santo said...

The MORAL implications IF this hypothesis be proved correct would be significant and at bad ways. I don't know if hbd scientists are mature enough to know the implications of any knowledge with that moral and historical charge. I would ''on fire'' if this was proved true. BUT...

Interestingly, we already have the birth order pattern to explain 8% of homossexuality ''cases''. I'm one of them. How explain that, it's higher the chance you have a homossexual son if he is the third of two all-male sons*

Anonymous said...

The problem as I see it for the bug hypothesis is, assuming the bug is sexually transmitted, the infected one (the totally gay man) is spreading the bug to the up-until-that-point uninfected by managing to have homosexual contact with young males disinterested in having sex with other men until after they have had sex with one! It isn't common enough for pubescent boys to have sexual contact with older males pressed on them for such a hypothesis to be tenable

There is some evidence to suggest that homosexuals were sexually abused as children at significantly higher rates than heterosexuals. This would be a plausible vector for the pathogen. But this isn't something that gets much attention or is investigated very much for political reasons.

https://www.ncbi.nlm.nih.gov/pubmed/11501300

"In research with 942 nonclinical adult participants, gay men and lesbian women reported a significantly higher rate of childhood molestation than did heterosexual men and women. Forty-six percent of the homosexual men in contrast to 7% of the heterosexual men reported homosexual molestation. Twenty-two percent of lesbian women in contrast to 1% of heterosexual women reported homosexual molestation. This research is apparently the first survey that has reported substantial homosexual molestation of girls. Suggestions for future research were offered."

Anonymous said...

So would pathogen X be the putative gay germ?

If I understand your argument correctly, you're saying that because people with HIV remain gay after taking HIV medication, and fungi and other bacteria appear to persist, the pathogen X is likely a fungus? And also that the pathogen X causes neurocognitive degeneration in addition to homosexuality?

But is there evidence that homosexuals without HIV tend to be afflicted more with neurocognitive degeneration than heterosexuals are?

Santo said...

I know syphillis has neurocognitive implications...

Santo said...

''There is some evidence to suggest that homosexuals were sexually abused as children at significantly higher rates than heterosexuals. This would be a plausible vector for the pathogen. But this isn't something that gets much attention or is investigated very much for political reasons.''

So, someone can explain how i get homo**

That's the problem about the fake ''rational'', non aparent emotional but you can deduct bias by this ignorance.

tomR said...

There are multiple advantages of being an low-masculinity male, both in reproductive aspects as well intellectual one.

1) Reproductive
Masculine men are likely to have masculine daughters, that may face rejection. Non-masculine, or feminine men stand a chance of having more attractive daughters.

http://www.sharonlbegley.com/why-doesn-t-evolution-get-rid-of-ugly-people

A tribe in which women choose to mate with just top 20% of most masculine men could soon face a situation (after many generations) where all women of such tribe are rejected and replaced with immigrant women, who still have feminine genes.

2) The most masculine brain structures are good for some tasks, but bad for others. To be sucessful a group needs both types of brain structures. Yin-yang?

Two most masculine types of brains are autistic/aspergers and type-1 pshychopaths - the ones that have no fear or remorse and/or are dominant.

Type-1 pychopaths have brains with more local connections, with multi-hop information propagation, rather than with a smaller number of large routing centers.

http://www.yalescientific.org/2019/02/wiring-of-psychopathic-brains-neural-networks-hold-clues-to-psychopathy/

Autists are known to be visual thinkers and pattern thinkers, who don't really get social stuff, and thus are not good at socially manipulating others (politics, religion). They are also worse at verbal communications than non-autists.

https://www.youtube.com/watch?v=MWePrOuSeSY
https://www.youtube.com/watch?v=PjE_yaJjXE8

Both types are good for some functions, but hopeless at others.

A non-masculine man would be someone with the advantages that females usually have - including being good at verbal communications and social manipulation (politics), but had unique male advantages over females like:

1) Male brain has like 6 extra years of development, maturing closer to 24, compared to females at 18.
2) No time wasted on being pregnant. And no time under too much hormones - that pregnant women have.
3) Brain still somehow larger than females, though smaller than masculine men.
4) Not being submissive - compared to females, but not dominant-aggressive either - compared to high-testosterone males. This is a reasonable place to be.

For example if you look at young Putin (looks, voice) he seems like a low-testosterone man. Good at political machinations. He is teamed with a somehow masculine defence minister Shoygu and in-between Medvedev. Notice that similarly a non-masculine Bill Gates teamed with masculine Paul Allen, and later Steven Ballmer to help run his company.

Judging from voice pitch good debaters eg. Ben Shapiro are also not heavily masculine.

tomR said...

3) Very masculine men face beging disliked and distrusted because of their looks and voice alone. While more feminine ones are seen as safe. This is explained by Stephen Porges's Polyvagal Theory.

https://www.stephenporges.com

4) This one is anectodal - from what I see the many non-masculine men hava a capacity to age very well. Eg. heterosexual Tom Cruise or gay Ricky Martin when it comes to celebrities. When it comes to people who didn't have plastic surgeries you can look at two gay youtubers: Plant Eats and Justicar, both looking younger than their age:

https://www.youtube.com/user/integralmath
https://www.youtube.com/channel/UCpfkq3uR963-bQPLWoWNDGQ

This is not universal, some low testosterone men age badly, eg Bill Gates.

5) Average testosterone in human males seems to be way to high compared to other species (and archaics were likely even higher!). Comaprison to male lion:

https://www.quora.com/How-much-serum-testosterone-do-lions-have-in-relation-to-humans

One can be a fully functional and successful male at much lower levels, like those buzzfeed guys:

https://www.dailywire.com/news/buzzfeed-guys-test-their-testosterone-levels-amanda-prestigiacomo

https://www.quora.com/How-much-serum-testosterone-do-lions-have-in-relation-to-humans

--
I haven't explained the phenomenon of homosexuality here, but just have shown that more non-masculine physique and brain, associated with both feminine heterosexuals and homosexual man can survive and even do well in the world.

Speculatively (low certainty) - it may be that homosexuality is some kind of defect that this type of bodies otherwise functional bodies are prone to? Especially as compared to testosterone-packed normals? Low testosterone = no protection from some random estrogen spike?

Peter Frost said...

Santo,

I'm not saying there is a single cause for male homosexuality (female homosexuality is much more malleable and not really the same phenomenon). The immediate cause is simply an insufficiently large population of neurons for attraction to women. If the neuronal population falls below a certain threshold, sexual attraction is channeled through the "default" of attraction to men.

That situation can arise through a combination of genetic reasons and maternal stress during pregnancy. But I believe there are pathogens that change sexual orientation as a way to facilitate their spread from one host to another. They probably spread to another host by means of intimate contact: genital, anal, or buccal.

Sean: "there are very few societies outside Melanesia where boys are sexually violated at puberty."

As one of the commenters noted, gay men are likelier to have suffered sexual abuse as young boys. Again, I'm not arguing that this is the only cause of male homosexuality. There are probably multiple reasons why some men develop a homosexual orientation.

I don't understand your comparison with the link between gum disease and Alzheimer's. Sexual orientation is a much more specific aspect of mental function. You might have a point if you could show that Alzheimer's has a selective effect on certain behaviors.

"But is there evidence that homosexuals without HIV tend to be afflicted more with neurocognitive degeneration than heterosexuals are?"

That would be something to look at. I've been looking for control studies on HIV-negative gay men, but so far to no avail.

Anonymous said...

And yet whatever went on on the past, there are very few societies outside Melanesia where boys are sexually violated at puberty.

Most of the historical examples of homosexuality seem to involve these sorts of "grooming" relations between adult men and adolescent boys/younger men in semi-institutionalized settings. Ancient Greece, the Catholic Church, British public schools, bacha bazi in Afghanistan, etc. The abused became the abusers e.g. priests tended to be former altar boys, headmasters were former pupils, etc. These cultural institutions and the grooming that went on in within them would have allowed the vector to self=perpetuate.

Even more recently, where homosexuality is no longer restricted and confined to particular cultural institutions and the grooming activities within them, homosexuals seem to develop similar type grooming type subcultures among themselves between older men and younger men who at least physically look like adolescent males. And prominent homosexuals who had relations and relationships with other similar aged adult men were also known to pursue relations with young boys. John Maynard Keynes was known for frequenting brothels in the Mediterranean and Near East that supplied boys. Gore Vidal vacationed in Thailand every year to visit similar brothels.

Sean said...

There are societies in Papua New Guinea where most boys by the age of 11 have become aggressive felators of men, or boys seek anal sex with men (the boys are told this is how they will become masculine). One wonders how these societies could have avoided a collapse if there is a gay bug that has a substantial impact.

Male homosexuals tend to be shorter, more weakly built with less masculine bone structure (hence the facial recognition algorithms can recognise them and even tell whether they take the feminine role). It is well established that the prenatal androgen exposure of homosexual men is less and this is reflected in their more feminine digit ratios. The basis for homosexuality must therefore be genetic selection against aspects of masculinity. Violence would seem the most likely target.

The Chimpanzee has a social structure ruled by fear. The alpha male swaggers about with his chest puffed out, while the other males look scared; females often return from sexual encounters with injuries. Frodo: Alpha Male "In 1997 Frodo’s reign of terror began as he usurped his older brother Freud’s position as alpha male of the chimps of Gombe.Born into the distinguished F-family, source of 4 alpha males to date, Frodo was blessed with a hefty size and powerful demeanor. Weighing in as one of the largest males at Gombe, this physical advantage was not lost on him.... His boldness wasn’t restricted to the social realm. Frodo was notorious for his drive and ability to hunt, with a particular taste for red colobus monkeys. Thus, from 1997 to 2002, no primate at Gombe was immune to Frodo’s wrath." The peace loving and sociable Bonobo species are lauded as the co-operative flower children hominid. They are also notorious for their homosexuality and paedophilia. Bonobo society is matriarchal, the high ranking females will bite a rowdy male’s finger off, but the mothers will assist their sons to mate with fertile females. Close to their mothers! And they have high pitched voices. https://www.researchgate.net/figure/Cognitive-and-behavioral-differences-between-chimpanzees-and-bonobos-that-align-with-the_fig2_. Physical parallells also exist Bonobo males are shorter, craniofacial less robust and don't have expanded chests.

"http://discovermagazine.com/2010/sep/25-modern-humans-smart-why-brain-shrinking Over the past 20,000 years, the average volume of the human male brain has decreased from 1,500 cubic centimeters to 1,350 cc, losing a chunk the size of a tennis ball. “When you select against aggression, you get some surprising traits that come along with it,” Wrangham says."

If you look at Cro Magnons they were barrel chested and had enormous heads. They were to modern humans as chimps are to bonobos. Sexually too I suspect. It is in the most advanced people one would find the weakest heterosexuality, and perhaps that is why civilisations in Europe have tended to collapse once there is open acceptance of homosexuality.

tomR said...

@Sean - "Weighing in as one of the largest males at Gombe, this physical advantage was not lost on him...." - here lies the problem. Chimps are TOO LARGE for recent and current state of forrest. Apes evololved in Miocene when the climate was hotter an wetter, so big, large, strong trees formed dense forests even in Europe. On such trees apes could sustain themselves.

Since then the climate changed, such forests are only found in the tropics. Everywhere else forests consist of either weaker trees, or trees that are strong, but not as densly packed as in the tropical forests. In such conditions large apes cannot exist. In most of the world large apes lost to more versatile monkeys - smaller, can suspend themselves on weaker trees. So "alpha maleing" DESTROYED chimps and other large apes as species - they should go SMALLER to accomodate to the new environment, but they couldn't because only the large alpha males could reproduce.

Anonymous said...

Sean, your Papaun and Bonobo examples would be examples of societies with increased vectors for hypothetical gay germs. You can't cite examples of homosexual behavior to refute the gay germ hypothesis since the behavior itself constitutes a vector.

tomR said...

@Sean

"If you look at Cro Magnons they were barrel chested and had enormous heads. They were to modern humans as chimps are to bonobos." - not necessairly. You may be confusing two separate things:
1) Neoteny
2) Feminization

Neoteny is the preservation of childlike features in adults. Humans are more or less neotenous apes. This is necessary, as the capacity to learn quickly and efficiently even as adults is crucial for us. Other animals learn very fast as children, but then they go into this grownup state, in which they loose the ability for rapid learning (relay on skills learned while young), instead concentrate on acquiring resources and mating. The cost of neoteny is being physically lest robust and weaker. More delicate but not necessairly feminine...

https://aegyokawaiisneurodiversityblog.wordpress.com/2015/05/29/forever-child-neoteny-and-neurodiversity/

Feminization is men looking like women, but not necessairly being delicate. Eg. a men with very wide hips and manboobs is feminized, an older man who still looks like a teenage boy is neotenous.


Sean said...

Anon, a superhighway vector for homosexuality in adults in certain societies of Papua New Guinea has not affected the birth rate there, but how could it not have if there was a std bug that made men uninterested in women? Most Papua New Guinea women are victims of rape.

tomR, Chimps and bonobos are equally genetically related to humans but they show different tendencies. Chimps are more kinetic and practical, while bonobos are social and serenely irresponsible. Within the humans species, some are interested in art and culture while others are more involved in concrete fixing of things. I think that some humans 9 months before they are born are already very close to homosexuality by virtue of their genes, and those are the ones a bug can tip the balance in. It is a prenatal thing. The most likely vector for actually existing bug that can completely flip (as opposed to merely nudge) sexuality would be as a vertical transmission bug, which in girls makes them hetero-sexier (a gay male with a beautiful sister). But then, why can't there be particular alleles that are more reproductively successful in girls than boys?

Sean said...

https://www.livescience.com/22179-evolutionary-battle-sexes-height.html
"In modern western societies, studies have found that women who are on the short side tend to have more children. In contrast, average-height men do the best, reproductively speaking, outpacing short and tall men in number of children fathered […]'We should not simply assume that when a trait is beneficial for one sex, that selection or evolution will necessarily favor this trait,' study researcher Gert Stulp, a scientist at the University of Groningen in the Netherlands, […] In the same way, traits that harm one sex but not the other may not be 'weeded out' by natural selection, Stulp said […] The results revealed that in short families, where both brother and sister were likely to be below-average height, sisters had more children than brothers. In average-height families, however, brothers had more children than their sisters.. […] “Because selection in this generation is then likely to be stronger on average-height men, the next generation will again be slightly taller,” Stulp said. “This is, of course, to the detriment of women, so that the selection pressure on female height will get stronger to push it back to shorter height again.”

This back-and-forth loop between slightly shorter and slightly taller generations will continue as long as evolutionary pressures for men and women remain different, Stulp said."

Santo said...

Well, It's what you're suggesting here...

How explain birth order homossexuality ''cases'', as mine*

About heritability, i have a wild speculation that one possible explanation to lower heritability or whatever it mean among identical twins, about homossexuality, is that basically homossexual men don't procreate with homossexual women. It's sound very wrong, and maybe it is. I just thought about it months ago. Just like if we have a minority of light eyes among a predominant brown eyes population and they never procreate one each other. If homossexuality can be defined as in someway ''recessive''...

Peter Frost said...

Santo,

I am not arguing that male homosexuality has a single cause. It seems to be the result of a genetic predisposition interacting with something in the environment, which may be a pathogen. But it can also be a traumatic event during pregnancy or fraternal birth order effects. Fraternal birth order seems to explain 15% of male homosexuality.

Male brains vary in their degree of feminization/masculinization, but this variance is subject to natural selection. Normally, genetic factors alone shouldn't produce homosexual behavior. At least, that is Greg Cochran's argument.

"Anon, a superhighway vector for homosexuality in adults in certain societies of Papua New Guinea has not affected the birth rate there, but how could it not have if there was a std bug that made men uninterested in women?"

Over time, there would have been counter-selection to increase the population of neurons that promote heterosexual behavior.

Anonymous said...

In the same way, traits that harm one sex but not the other may not be 'weeded out' by natural selection

Claims like this regarding homosexuality can be reduced to a simple math problem, no? Take the fitness cost to male homosexuals and figure out the hypothetical gain in fitness among their female siblings necessary to maintain genetic homosexuality. What do the numbers look like? Are they plausible? Then compare them with empirical data.

Santo said...

Natural selection doesn't select just for all imediately useful phenotypes specially in relaxed one. What i said previously ...

Every selective process is likeable to result in diversity.

Well.. again, you're suggesting a single cause. Doesn't matter how you write. A manipulation of words don't make beliefs true.

Interestingly, the same ''traumatic effect''.

''Traumatic effect'' must be chaotic or without pre-determined factors.

Your language is not based on science, sorry, but about your homophobia. Unecessary offense based on your expected emotional reaction and not ''what's really mean or is''.

Unfortunately, most of what so-called science is based on white heterossexual male biases, no matter how bright your technology shine.

Sean said...

"Claims like this regarding homosexuality can be reduced to a simple math problem, no? Take the fitness cost to male homosexuals and figure out the hypothetical gain in fitness among their female siblings necessary to maintain genetic homosexuality. What do the numbers look like?"
One cannot assume modern Western upbringings are any more neutral on homosexuality than the ones in Melanesia that turn males into aggressive felators of men by the age of 11 or 12. There might have once been an advantage in these genes that had little or nothing to do with sex, which the simple mathematics of total hetrosexualty competed with total homosexuality is missing. To be specific, a man who raped and murdered would be likely to be put to death by others in his band. I don't find it implausible that AOTBE genes for reduced masculinity (sometimes even homosexual tendencies) would have resulted in men less likely to be condemned to death by mob justice. The selection pressure for hetrosexuality may have been overborne by the selection against the violence that went with homosexualty, and those less aggressive men tending to have sexy sisters rather than diesel dyke ones like the most heterosexual men, which is something that may have had a big effect if women were under a period of sexual selection. Many ancient Western societies tolerated homosexuals as much as modern primitive ones do; if anything, it seems the more advanced ones are those in which as time went on the cultures increasingly counteracted homosexuality. Modern mass culture posits extreme violence ('Licensed to kill') as the ultimate in heterosexualty (James Bond, John Wick ect).

I happen to think the trend in human evolution of a less robust physique (especially that marker of domestication in animals, reduced bone density) is a feminizing one. The most advanced people like the Puritans could be biologically and innately of gayer propensities that Papua New Guinea tribesman in the same way the New Englanders had hereditarily lower bone density than Melanesian warriors. There is cultural suppression of homosexuality in Western culture, which may be a case of an advanced culture evolving to do the heavy lifting of preventing spread of non violence genes (with the side effect of homosexuality) affecting the birth rate. The current Brazilian president objects to gay foreigners flocking to his country for its world class butt boys. He is also a fan of Death Squads.

Sean said...

Correction:

The selection pressure for heterosexuality may have been overborne by the selection against the violence that went with heterosexualty, and less aggressive men tending to have sexy sisters rather than diesel dyke ones like the most heterosexual men, which is something that may have had a big effect if women were under a period of sexual selection.

Peter Frost said...

Sean,

You're arguing along the same lines as Edward Miller. In order to increase monogamy and paternal investment, natural selection favored a higher level of feminization of male brains. "Dads" are thus, on average, more feminized than "cads."

"The survival of a human predisposition for homosexuality can be explained by sexual orientation being a polygenetic trait that is influenced by a number of genes. During development these shift male brain development in the female direction. Inheritance of several such alleles produces homosexuality. Single alleles make for greater sensitivity, empathy, tendermindedness, and kindness. These traits make heterosexual carriers of the genes better fathers and more attractive mates. There is a balanced polymorphism in which the feminizing effect of these alleles in heterosexuals offsets the adverse effects. (on reproductive success) of these alleles' contribution to homosexuality."

https://link.springer.com/article/10.1023/A:1001836320541

I think Ed Miller is half-right. Men are mentally feminized to varying degrees, but normally natural selection would prevent this feminization from crossing the line that separates a heterosexual orientation from a homosexual one. That's why I think there must be an environmental factor (fraternal birth order, trauma during pregnancy, a pathogen, etc.) that pushes some men over that line.

Anonymous said...

and those less aggressive men tending to have sexy sisters rather than diesel dyke ones like the most heterosexual men, which is something that may have had a big effect if women were under a period of sexual selection

That's why I suggested that your claims could probably be reduced to a fairly simple math problem.

Natural selection produces all kinds of strange creatures and you find it hard to believe that there could be men who are both heterosexual and not impulsively, uncontrollably violent? Don't you think something like, say, a platypus is strange, not a heterosexual man who isn't impulsively violent?

There are many animal species in which the males are completely heterosexual but not impulsively violent. They generally avoid each other, or compete against each other for mates in various non-violent ways, or engage in ritualized fights that don't end in death.

Anonymous said...

I happen to think the trend in human evolution of a less robust physique (especially that marker of domestication in animals, reduced bone density) is a feminizing one.

Humans still reproduce sexually, so any sort of trend you posit would have had to have coevolved with heterosexuality. Otherwise, the trend wouldn't exist.

Bond exercises violence on behalf of a higher authority. He's "licensed" by the British government. Wick is an assassin for hire who kills out of vengeance or to protect himself or out of some sort of moral code. They're not examples of impulsive violence

Sean said...

Humans have weapons and can conspire so people who make everyone nervous can be put an end to with no risk. John Wick is killing on the pretext of avenging his pet Beagle. Think to yourself which is the more heterosexual animal, a Beagle or a wolf. Of course the domesticated dog Beagle breed didn't get that way by natural selection. If you eliminated the natural alpha males from a wolf pack the gene pool would change.

I believe that there could be men who are both impulsively, uncontrollably heterosexual and timid, but there would be a considerable valley to be crossed before that fitness peak was reached. Natural selection never goes into the valley. Recombination does.

Sean said...

Yet another correction to Oct 8 comment:_ There is cultural suppression of homosexuality in Western culture, which may be a case of the most advanced civilisation preventing spread of actual homosexual behaviour from the reduced masculinity genes affecting the birth rate.

Peter, Yes. But the child a dad brings up might be a cads, if the dads let the cads live. Carlton Coon said the older men getting together and doing away with a wayward young man in the night was a common phenomenon.

Anonymous said...

I believe that there could be men who are both impulsively, uncontrollably heterosexual and timid, but there would be a considerable valley to be crossed before that fitness peak was reached. Natural selection never goes into the valley. Recombination does.

I'm not sure why you find this hard to believe. The completely heterosexual and extremely horny guy who's nevertheless too shy and timid to directly obtain sex in some impulsive fashion is an extremely common type in advanced societies. It's a cultural trope, and movies are frequently made about this.

Sean said...

Yes, in "advanced societies" that is a trope, but movies tend not to feature men paying for sex. Homosexuals in work earn more than heterosexuals.These are people whose homsexual genes are just damaged genes according to the gay germ fellow.

I went to get Andreas Wagner's new book yesterday and bought Wrangham's book too. From flipping through it I am more convinced than ever that selection against violence reduces heterosexuality and leads to adult homosexuality. The domestication syndrome in mammals includes the craniofacial, skeletal and coat change (including the 'blaze' or white stripe on the forehead) and more frequent and nonseasonal estrus cycles, big sexual change right there. In the relatively peaceful stumptail manques (which go bald and lose their ruddy face colour as they age) male male mounting with anal penetration has been observed.

Sean said...

The male homosexualty genes in the recent study include one associated with male pattern baldness.

Anonymous said...

Male pattern baldness is caused by dihydrotestosterone, which is produced by testosterone. Eunuchs don't go bald.

Anonymous said...

Yes, in "advanced societies" that is a trope, but movies tend not to feature men paying for sex.

Not sure what you mean here.

I suspect it's the opposite of what you claim. That it's the impulsively violent types that you identify with heterosexuality that are more likely to engage in homosexuality, if only because they have more difficulty controlling their sex drives and avoiding to engage in predatory homosexuality.

tomR said...


About: "studies have found that women who are on the short side tend to have more children. In contrast, average-height men do the best, reproductively speaking, outpacing short and tall men in number of children fathered"

Estrogen is a height growth blocker, but it is also a growth hormone for bones, especially lower body bones. In order to be a physically very strong man you need both testosterone for upper body and estrogen for lower body.

If a man has low estrogen, or little or no estrogen receptors he can grow VERY tall, but with serious bone strenght problems.

https://www.latimes.com/archives/la-xpm-2007-jan-15-he-staturegirls15-story.html

https://www.nytimes.com/1994/10/25/science/deaf-to-estrogen-s-call-a-man-s-strange-story.html

This low-estrogenic look seems similar to the way North-Western Europeans (Netherlands etc.) look - tall, thin, but not particularly muscular, with women having small boobs. They also have longer development times (eg. Hajnal Line), which is good for the brain.

An example Hajnal Line woman - elongated, thin, small boobs and virgin until 28, then becomes sexual
https://www.youtube.com/watch?v=pusGHIzOuH0

Anonymous said...

This low-estrogenic look seems similar to the way North-Western Europeans (Netherlands etc.) look - tall, thin, but not particularly muscular, with women having small boobs. They also have longer development times (eg. Hajnal Line), which is good for the brain.

Southern Europeans and Mediterraneans tend to be more gracile than Northern Europeans, who aren't just taller but have larger bones. Strength athletes, strongman, American football linemen, etc., tend to be dominated by Northern Europeans.

Sean said...

Everyone identifies criminal violence with hetrosexuality, just as everyone associated baldness with being harmless and a bit gay. And now we know they were right. Another one of the gay snps has to do with smell. https://www.youtube.com/watch?v=cGCZB8jUxRc

Anonymous said...

I've never heard of baldness being culturally associated with gayness. The gay culture seems to place a premium on a very youthful male appearance that's been relatively unaffected by the development of certain secondary sexual characteristics such as facial and body hair, and by the decline or loss of heard hair:

https://en.wikipedia.org/wiki/Twink_(gay_slang)

Twink is gay slang for a young man in his late teens to early twenties whose traits may include: general physical attractiveness; little to no body or facial hair; a slim to average build; and a youthful appearance that belies an older chronological age.

There is a gay subculture involving so-called "bears", which refers to older, physically large and imposing men with body and facial hair and often head hair decline or loss, but a major aspect of this subculture is that these "bears" don't physically resemble stereotypical gays.

"People are psychologically biased to see bald men as dominant leaders"

https://www.independent.co.uk/news/business/people-are-psychologically-biased-to-see-bald-men-as-dominant-leaders-a7872761.html

"according to research from the University of Pennsylvania, there's something powerful about having a smooth dome.

In three experiments, researcher Albert Mannes found:

• "Men with shaved heads were rated as more dominant."

• "Men whose hair was digitally removed were perceived as more dominant, taller, and stronger than their authentic selves."

• "Men experiencing natural hair loss may improve their interpersonal standing by shaving."

Now a data scientist for the US government, Mannes argues that the shaved-and-dominant link comes from cultural associations, in the same way that being tall and having a deep voice each signal dominance.

"In US society ... shaved heads are often found on men in traditionally masculine professions," he writes, "so dominance may emerge through stereotypical associations with these figures."

When guys decide to shave off their hair, they're tapping into a cultural history of close-cropped dominance, from Michael Jordan imposing his will on the basketball court to Bruce Willis saving the day on the silver screen.

In fact, Mannes says that he was inspired to do the research when people were more deferential to him after he shaved his head.

It's not all good news, though: Mannes also discovered that while men with shaved heads are seen as more dominant, they're also perceived as looking four years older than guys with hair. Not only that, but the bald dudes are found to be less attractive."

Sean said...

https://static.businessinsider.com/image/596cd260a47cb56b008b4a01-1200/image.jpg.

Anonymous said...

I sign under everything Santo wrote:

Two reasons why conserfs like you and Coch want to spread this theory

- first: homophobia
- second: incapacity to fully understand natural selection..

First of all, humans evolved to be capable to differentiate sex from procreation. To control sex impulse as well to use it in recreational related-activities. It's mean non-reproductive sex desire seems to be in-selection among humans, too. Broader is the sexual behavior spectrum, more diverse it will be;

Secondly, sexuality is correlated with cognition and personality. Humans evolved to be psychologically and cognitively diverse because it's better have different specialist types to solve different problems. So it's expected a mix among so-called masculine and so-called feminine traits, and it's also mean about sexual desire. A matter of probability;

Thirdly, only very strong and specifically-defined natural selection can ''clean'' population's related phenotypes from ''debris'' as homossexuality.

There are some anecdotal evidence of more common bissexual behavior among heterossexual african-descent men... R-strategy or huge fertility to attacks environmental challenges also mean trends to higher phenotypical variation or hyper-sexuality maybe;

Fortly, your evidences sound very weak, like a incident correlation... only way to prove it it's finding direct association between fungus and behavior. Like, in the exact way, a homossexual guy feel sexual desire to another male, so-called ''germ'' manifest in the brain. Also, what i already said in Pumpkin Person blog. If you find some microorganisms, unusual ones, in healthy homossexual male sperm, so, this theory also possibly will have some breath.

Fifhtly [whatever]: you know we have the similar number of bacterias and cells, right*

I don't believe if there is a ''gay germ'' will not have a ''sexual germ''.

That's the problem about science without philosophy, i mean, not verborragic crap lots of white thinkers had produced, and i'm including many ''non-liberals''. Scientists put their personal biases over ethics.

To fully understand homossexuality we must understand all sexuality. Why not try to understand the biological origins about heterossexual behavior**

Still about heritability. Autism seems pretty heritability and some people also believe it's a kind of ''brain infection''. Higher or lower heritability may mean less than we bet. And all the time people is confusing heritability with inheritance levels, what's matter for selective processes.

How explain one of the identical twin pairs with no ''fungus/pathogen/germ infection''*

AND MORE

Sexual abuse or maternal stress don't cause male homosexuality
https://www.researchgate.net/publication/11091252_Prenatal_Stress_and_Gender_Role_Behavior_in_Girls_and_Boys_A_Longitudinal_Population_Study
https://pubmed.ncbi.nlm.nih.gov/26619850/

And if there is a "gay germ", then surely there would also be a heterosexual germ

Anonymous said...

I am alarmed at some of the comments on this blog passing for scientific discussion--you are speaking of people as if they have a disease. The way some of the commentators have talked about homosexuality reminds me of 19th century discussions of eugenics regarding Black people--where the speaker is completely unaware of their bias and power in the discussion. Be careful about that--if you speak about a group of people as if they were statistics or lab experiments, it will discredit anything you are trying to say. It's fascinating for example how many assumptions have been included in the discussions--that homosexuals are weaker than heterosexuals (regarding indigenous cultures) or that homosexuality implies a feminization of men (really? is that always the case?) or the fact that homosexual women have been conveniently left out of the conversation entirely. Constructing a thread along these lines says more about the contributors than it does about the topic! For my part I would suggest that 1) sexual identity is not reducible to sexual activity, it is not the same thing, and what constitutes sexual identity is far more complex than is being understood in this thread. 2) evolution and natural selection could be twisted into explaining homosexual ACTIVITY, perhaps, as has been shown, by additions that are far fetched at best (viruses for example) but it does not explain sexual identity (love idealization, spirituality, worldview). 3) Because of this, a biologistic explanation of sexual identity will inevitably fail under the weight of its own presumptions and lack of complexity that must factor in non-biological variables.

Anonymous said...

"the only common denominator being the gay lifestyle" - what is the evidence for this assumption?

Your sources don't mention (or indicate) anything like that, at least I've never seen

I guess you're lying again as usual

Anonymous said...

Another problem about your approach is

how can you prove that heterossexuality or sexuality per si is not also the result of pathogen manipulation