| Revision as of 16:53, 16 October 2020 editSabakaw (talk | contribs)88 edits Update Evolution and Biology of Sex - THURS LAB assignment detailsTags: Manual revert dashboard.wikiedu.org [2.2]← Previous edit |
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|1={{cite journal |last1=Swift-Gallant |first1=Ashlyn |title= Organizational Effects of Gonadal Hormones on Human Sexual Orientation |date=2023 |publisher=Springer |DOI=10.1007/s40750-023-00226-x |pages= 344–370 |url= https://rdcu.be/dKFPC |language=en |journal=Adaptive Human Behavior and Physiology |url-access=limited}} |
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|2={{cite journal | vauthors = Bailey JM, Vasey PL, Diamond LM, Breedlove SM, Vilain E, Epprecht M | title = Sexual Orientation, Controversy, and Science | journal = Psychological Science in the Public Interest | volume = 17 | issue = 2 | pages = 45–101 | date = September 2016 | pmid = 27113562 | doi = 10.1177/1529100616637616 | doi-access = free }} |
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{{dashboard.wikiedu.org assignment | course = Misplaced Pages:Wiki_Ed/Southern_Methodist_University/Gender,_Sex,_and_Sexuality_Global_Perspectives_(Spring_2019) | assignments = ] | start_date = 2019-01-22 | end_date = 2019-05-02 }} |
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{{dashboard.wikiedu.org assignment | course = Misplaced Pages:Wiki_Ed/University_of_Puget_Sound/Evolution_and_Biology_of_Sex_-_THURS_LAB_(Fall_2020) | assignments = ] | start_date = 2020-08-31 | end_date = 2020-12-18 }} |
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{{dashboard.wikiedu.org assignment | course = Misplaced Pages:Wiki_Ed/California_State_University_Channel_Islands/Introduction_to_LGBT_Studies_(Fall_2020) | assignments = ] | start_date = 2020-08-27 | end_date = 2020-12-10 }} |
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{{dashboard.wikiedu.org assignment | course = Misplaced Pages:Wiki_Ed/California_State_University_Fullerton/Gender_and_Technoculture_(Spring_2022) | assignments = ] | reviewers = ] | start_date = 2022-01-24 | end_date = 2022-05-13 }} |
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== Undated Citation Needed tags == |
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== Twin studies / theories of cause == |
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Probably best to update the twins studies to the meta-analysis in Bailey's 2016 review rather than primary sources. I don't really think the 'criticisms' needs its own heading (just look at the citations for it, good lord). It's not about it being a random sample and its not about MZ concordance rates, but about (a) the difference in MZ and DZ probandwise concordance rates, and (b) the statistical model of genetic and environmental influence – and as Bailey points out, the only plausible model from these together is the multifactorial threshold model. ] (]) 10:01, 2 July 2020 (UTC) |
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:I'm wondering about the structure of this article in general. Should everything be under one giant 'empirical studies' section or separated under heading type 1? I am also surprised there is no section dedicated to hormones given the substantial volume of evidence related to androgen uptake shown through digit ratio and ear structure. ] (]) 10:54, 2 July 2020 (UTC) |
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:Additionally, I'm not sure having a section titled '''"Empirical studies"''' is right? ] (]) 11:09, 2 July 2020 (UTC) |
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::Regarding ? Yes, criticisms should be included. Both here and at the ] article. |
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::I'll think on the headings. ] (]) 21:14, 2 July 2020 (UTC) |
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:::Agree, I just don't think it warrants a subheading because it can be mentioned very easily in the middle of the history of events. I.e. research began with early self-selecting studies, the criticisms came, and then more recent twin studies relied on the random contacting of people in population twin registries. Bailey 2016 is the most comprehensive meta analysis and the median of .24 concordance is the best available and as close to the true rate as anyone can get (thus far). ] (]) 07:20, 3 July 2020 (UTC) |
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::: Regarding the headings, one thing I find odd is on mobile a lot of the actual ~interesting content~ sits under empirical studies, but it’s long and drawn out. I feel like it could just be split according to genes, hormones, FBOE, physiology etc? My eyes just go to ‘biological theories as a cause’ and I’m left unimpressed. I know it means more sections, but many of these could be more encyclopaedic in nature. The current genetic subsection, for example, is rather long winded and at times redundant. |
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:::There also needs to be some thought about the ‘biological theories’ section. First, what actually counts? For example, the maternal immune response hypothesis (FBOE) is really it’s own theory of a distinct cause. But other things could also be interpreted as a ‘biological theory for the cause’ that tie into evolutionary biology, like genes causing increased fecundity in women, and causing androphilia in men? This section could technically grow to be quite sizeable. I’m sure that’s not a bad thing, though. |
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:::I also don’t know if the ‘early fixation hypothesis’ is the correct title given for that first paragraph. It seems more like brain arrangement hypothesis. Correct me if I’m wrong, but wasn’t early fixation more of the Oedipal/Freudian explanation of early psychoanalysts? I’ve never heard that phrase in a biological context. ] (]) 23:22, 2 July 2020 (UTC) |
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::::Regarding "early fixation", I changed that terminology with edit. It seems like the maternal immune hypothesis is an aspect of that; I wouldn't say off the top of my head that that's a distinct theory, but if the sources do treat it that way, then okay. With splitting or rearranging the "empirical studies" section, I'd have to think about that. If you have a specific proposal, that may help. Maybe the section at the bottom about anatomy should be combined with that as well in some way. However, I don't think discussion of evolution should be combined with theories about development in the individual; this is because of the difference between proximate and ultimate causes, as explained at ]. <span style="font-family:Palatino">]</span> <sup>]</sup> 03:57, 3 July 2020 (UTC) |
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:::::That seems pretty good. That way sub headings could be incorporated under it to briefly describe a few related hypotheses, e.g. Maternal Immune Response for some men (FBOE), and androgen receptivity/uptake in others which all relate to brain arrangement or wiring (I am just brainstorming here). I've recently read a lot of responses to Breedlove 2017 in the Archives of Sexual Behavior, and they were really fascinating since brain arrangement with relation to androgen could be manifesting itself in so many different ways. LeVays was brief and good. McFaddens explanation of androgen uptake (and hyper-masculinzation producing a monotonic effect), rather than simple under/over exposure, was perhaps the most interesting. I was surprised to see biologists are finally taking seriously the research out of US/Canada/Sweden with relation to sexual orientation and facial structure. Especially after a longitudinal research was published showing masculinization/feminization of face is highly influenced by androgens. There's probably also room to mention the possibility of different typologies of gay men down this line of reasoning, the fact that some researchers like Bailey think that while there may be multiple prenatal influences, that ultimately they may come through one single final pathway of sexual orientation (i.e. no different typologies, only androphilic or bisexual brain formation). |
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:::::With regards to structure, it's hard to picture things another way when they've been set in that format for so long. My general feeling is that it should be easy for users to access certain parts, and given most traffic probably comes from mobile - shorter sections with descriptive H1 titles are useful. The easiest path would probably be to switch a lot of the subheading's into H1 headings... i.e. genes, epigenetics, birth order, fertility and heritability studies, brain structure, physiological differences, gender nonconformity, quasi-experiments (boys reassigned female) and animal research (in no particular order here). Maybe this is a lot of headings, but IMO it makes more sense given how far one has to scroll through the genes section (including that table) to get down to all the rest (on mobile). Many people would probably dry up reading all those gene studies, since it's stated quite early on how much of a role genes play. If it was me, I'd want to move on to other explanations by then and scroll to the next section, but on mobile you're not sure whats coming next. The theories could still remain in place below these areas to explain how all those things interlink. I might be way off base here, and I don't think it should be changed in a rush. Maybe there's a better way, but I get the feeling that since each area of research is quite substantial it would be good to have separate headings. We can take our time. ] (]) 07:20, 3 July 2020 (UTC) |
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::::::Agreed that the brain development subsection needs expansion, and the sources you mention here could be used for that. As for the headings, lets all think about that for a while. I might have to look at ] to see how much of a role mobile appearance plays in heading layout. <span style="font-family:Palatino">]</span> <sup>]</sup> 22:08, 3 July 2020 (UTC) |
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::::::I'm not a fan of a lot of headings (subheadings or otherwise), and especially if the headings only contain a little bit of material (see ]). The reason I'm not keen on extra subheadings is because, like I've noted times before on Misplaced Pages, it can make Misplaced Pages articles look substantially longer than they are from the table of contents. And this can make the article difficult, or more difficult, to navigate through. To combat clutter in the table of contents, <del>]</del> ] is sometimes used. But I'd prefer to just not add excessive subheadings. |
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::::::As for naming the headings, and the article setup, we could work that out in a sandbox by proposing one or more examples. It's easier to get a better idea of what we mean and agree on in that way. The visual is helpful like that. ] (]) 02:29, 4 July 2020 (UTC) |
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Just regarding brain arrangement theories. This kind of splits into three main subcategories (as far as I am aware). The first is '''neurohormonal theory''', linked to the exposure of androgens, or the uptake/sensitivity to them along certain regions of the brain. Then it splits into '''two different maternal immune response hypotheses'''. The first is the anti-male antibodies as demonstrated by the FBO effect. The second is a maternal immune response unrelated to male antigens, and Blanchard has (so far cautiously) implicated it in first born gay sons and even lesbians. Blanchard found that mothers with first born gay sons and lesbians had less successive children, perhaps indicating that this type of antibody effects sex differentiation processes, but unlike FBO effect, it is detrimental to the viability of future fetuses (I think it was even stronger in mothers with lesbian daughters). He did leave a comment in a journal recently that he has another paper with data coming out shortly. Since all of these three brain arrangement theories would implicate atypical sex-differentiation processes, there can be homosexuals with physiological outcomes that look attributable to neurohormonal theory but may be truly attributable to antibodies. For example, Marc Breedlove always seems to regurgitate his masculinized digit ratios for lesbians, but ignores Richard A. Lippa's (one of the largest) with a sample of N=2,000+ which found gay men had feminized digit ratios, and lesbians had no differences with straight women. Theres another paper in the mid-2000's with similar findings. I think the vast majority show lesbians having masculinized ratios (at least butch ones) but they are smaller than Lippa's. It gets quite complex. This may be related to a variety of different cause typologies as LeVay points out, where some are related to androgen receptivity and a third is related to antibodies – and then how much of this also implicates gene for androgen receptivity? Unfortunately the media and LGBTQ activist/groups appear to have moved largely back to a social constructionist view, for example, ] is frequently quoted in NYTimes articles bashing any study that implicates biology and sexual orientation, because that would mean she had to cede ground on sex differences. I guess they also don't want there to be a biological implication because it could mean prevention of sexual orientation? Anyway, J. Michael Bailey doesn't even care for physiological markers because behavior that emerges with no encouragement, and despite opposition, is the "sine qua non of innateness". In his view gender nonconforming children fare the "poster child for biological influences on gender and sexuality, and this is true whether or not we measure a single biological marker". These perspectives are outlined in a variety of papers but if I propose some edits I'd want to refer to all of the evidence (excluding the social constructionists argument, which I might briefly cover in environment/sexual orientation?). Let me know if I am missing something. ] (]) |
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:Okay. I'd encourage you to keep working at it until you have written what you feel is a well-rounded overview, and then you can add it to the article or propose it here first; discussion and tweaks can then follow either way. I don't think we need to discuss social constructionism in this article. That is in fact discussed at ], but I need to work on that section. |
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:Regarding "the media and LGBTQ activist/groups appear to have moved largely back to a social constructionist view", I don't think I would go quite that far, but it does seem to me there has been a shift in this regard over the last several years. And we do definitely hear some pro-LGBT people nevertheless (and foolishly, in my view) endorsing social learning or constructionism, whereas a few years before that was almost always associated with the religious right. The idea has long existed in some parts of academia, though, but scientific research has since moved beyond that. <span style="font-family:Palatino">]</span> <sup>]</sup> 03:21, 5 July 2020 (UTC) |
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Crossroads, re: social constructionism, you may have already read it, but J. Michael Bailey has a great chapter on this topic in The Man Who Would Be Queen, titled “is homosexuality a modern invention?”. The entire book is available on researchgate. It’s an amusing critique of the social constructivism view. ] (]) 14:03, 14 July 2020 (UTC) |
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:Thanks. Yeah, I've read the book. Regarding criticism of social constructionism, you may find these sources interesting and/or useful.<ref>{{cite book |last=Norton |first=Rictor |date=2016 |title=Myth of the Modern Homosexual |url=https://books.google.com/books?id=DkTqDAAAQBAJ&printsec=frontcover#v=onepage&q&f=false |publisher=Bloomsbury Academic |isbn=9781474286923 }} The author has made adapted and expanded portions of this book available online as .</ref><ref>{{cite book |last=Boswell |first=John |chapter=Revolutions, Universals, and Sexual Categories |editor1-last=Duberman |editor1-first=Martin Bauml |editor2-last=Vicinus |editor2-first=Martha |editor3-last=Chauncey, Jr. |editor3-first=George |date=1989 |title=Hidden From History: Reclaiming the Gay and Lesbian Past |publisher=Penguin Books |pages=17–36 |chapter-url=https://pdfs.semanticscholar.org/d1f4/b4d6d8a37a3470c63ae83bf0d4a5101b08ce.pdf}}</ref> Bailey et al. cited both of these among others in their 2016 review. There may also be other sources along those lines which I am not familiar with. <span style="font-family:Palatino">]</span> <sup>]</sup> 04:29, 15 July 2020 (UTC) |
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{{reftalk}} |
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There are 3 undated Citation needed tags. One of them is from March 2007, so if someone more familiar can take a look and see whether they are still needed. Thanks ] (]) 05:08, 26 March 2023 (UTC) |
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== Considerations == |
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== Sexual Orientation in Twins: Evidence That Human Sexual Identity May Be Determined Five Days Following Fertilization == |
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I have raised questions over some of the pages in the past, but I am trying to get some specificity here. Under ''Biological'' influences, there are pages for |
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PMCID: PMC10757681 DOI: 10.7759/cureus.51346 |
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* Neuroscientific |
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The disparity in sexual identity in monozygous twins may relate to the time of splitting of the zygote– twins resulting from splitting on or before day 5 after fertilisation are free to develop their own sexual identity; twins splitting after day five have the same identity. |
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* Epigenetic |
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* Birth order |
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* Prenatal environment (which links to an article titled ''prenatal hormones and sexual orientation''???) |
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See: ] (]) 03:12, 31 December 2023 (UTC) |
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But, prenatal environment can obviously include immunological responses rather than just "prenatal hormones" as is implied by the actual article title. It's starting to look more and more like the majority of male homosexuality may be the result of immunological responses, since the antibody found in the fratenral birth order effect was more present in mothers of first born gay sons who had no older brothers (perhaps a thinner placenta leads to the maternal response having more power in such a first born). I've seen a lot of research out of Sweden indicating that first born sons are much more likely to pursue fields like engineering and politics, while later born sons are more likely to pursue art school and journalism (gay or straight)... and this often chalked up to 'parental investment of time' into first borns by sociologists... but really, it's likely that some portion of mens interest in masculine/feminine behaviors may also be the result of interplay between immunological responses and development. If all pregnant women began taking a drug which shielded developing fetuses from NLGN4Y Y-linked antibodies (in the hope of preventing a gay son), you'd likely start to see more 'feminine' traits in men disappear, and men on average would begin to skew much more to masculine/aggressive traits/behaviors. For many reasons, such a society would probably be hampered on creativity, trust, and maybe even fertility (given many heterosexual women opt for some level of femininity in men). I only put such theories here, which are supported by many scientists, as to explain how immune responses apply in a much larger way than was previously thought. This also means that FBOE very likely does apply to more than just gay men with older brothers (as is implied by boegart). Regions like Latin-America where historical birth rates were around 7 in the 1970's have a lot more homosexuality than regions like Scandinavia where birth rates sat at about 2 for the past 50 years, therefore immunological responses could explain the vast majority of gay men in such cultures... the 15-29% calculations apply to the mostly white/western datasets Blanchard had access to. |
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:Bad paper, incorrect twin concordance, for example. ] (]) 02:58, 24 May 2024 (UTC) |
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In addition, other immune responses (potentially involving blood groups) may have some explanation for other homosexuals and even lesbians (as i've mentioned before). My '''main question''' is to whether or not prenatal hormones is the correct title, or, if there needs to be a separate article for prenatal maternal immune responses?? I don't like how there are so many articles separated in general, but I feel simply having 'prenatal environment' (as it is titled under the sexual orientation infobox/sidebar) linking to a page specifically about prenatal hormones seems a little outdated/inaccurate. |
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== Comment == |
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I know it's annoying to have to restructure and reorganize. A '''side note '''and as and example, I've pointed out previously on this talk page, that opening with 'genes' is a little lackluster given genes have been a very disappointing field of investigation with regards to sexuality. I'd say it should be shifted below hormones or prenatal development... or maybe the article should begin with the basics of fetal development and sex-differentiation. As soon as you can grasp the fact that brain masculinization as a result of sex hormones begins at 8 weeks, it's rather easy for people to grasp how other genetic/hormonal/immunological components all play a role in that process and may effect whether one is androphilic, gynephilic or somewhere in between. ] (]) 00:33, 16 July 2020 (UTC) |
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:I edited the sidebar to match the article title. Otherwise, as you know, we are bound by the reliable secondary sources, which means we aren't on the cutting edge of the science (and scientists can't always tell in the midst of it all which avenues will pan out and which will be dead ends). With regard to 'prenatal maternal immune responses', as far as I know, the sources overwhelmingly talk about that in context of the FBOE, so I don't see the need for renaming or spinning out anything at this time. With regard to mentioning genes first, I believe we do this because the sources do, and they likely do it because ultimately, the very first thing someone starts out as is their genome, basically, with prenatal environmental effects happening after that. Yes, there is overlap between the different articles on the causes of sexual orientation. We'll chip away at improvements and discuss specifics as we go. <span style="font-family:Palatino">]</span> <sup>]</sup> 04:29, 16 July 2020 (UTC) |
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::Thanks, and no worries. I still think that hormones should come first. It comes first in the Bailey et al. 2016 review, and in my time reading a lot of Blanchard papers recently, he frequently makes an opening statement similar to (which was coauthored by a lot of researchers): "'''''As noted by Blanchard (2008), the maternal immune hypothesis does not challenge the long-standing theory that sexual orientation is primarily influenced via prenatal sex hormone exposure'''''", so I think that does underscore that neuroendrocrine/hormonal theory has and will continue to be the most relevant. In addition, Bogaert's 2018 puts prenatal hormones before genetics. ] (]) 09:57, 17 July 2020 (UTC) |
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Hi {{u|CommonKnowledgeCreator}}, thanks for your contribution to the evolution section. However, Misplaced Pages generally relies on secondary sources. I think you've included excessive focus on the kin selection and antagonistic pleiotropy hypotheses, mostly using primary source studies. It's great there is an overview of the history, but we only need to cite secondary sources on the general consensus on these models. ] (]) ] (]) 02:58, 24 May 2024 (UTC) |
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== Discussion == |
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:I am more than aware that Misplaced Pages generally relies on secondary sources. However, per WP:BMI, this is not a medical topic and one that appears (after a search of Google Scholar) to have few secondary sources that systematically review the subject (as most of the content does not appear to systematic reviews or meta-analyses), and WP:RS does not preclude primary sources and only states that secondary sources are preferred. As far as evolution and homosexuality are concerned, kin selection and antagonistic pleiotropy are the two main evolutionary hypotheses for homosexuality, and there does not appear to be a consensus about whether either is true. The only review using Google Scholar that I found that discusses kin selection or antagonistic pleiotropy does still suggest that the latter is a plausible hypothesis. -- ] (]) 03:28, 24 May 2024 (UTC) |
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Hi Flyer, I see what you mean. I only ordered it in that fashion because of the Bailey review, and since it sort of relates to hormonal exposure/brain masculinization (but I guess t lacks direct evidence of the cause) But we can change that. I’ll do a proposal soon. ] (]) 05:39, 9 October 2020 (UTC) |
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::I'm not convinced of this argument for including so much focus on primary source studies? Many studies have questionable effect sizes, which is why it's best to avoid them, especially on a topic as controversial as this. As for not being able to find reviews, they are better reviewed and criticized in text books. |
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::{{tq|"Kin selection and antagonistic pleiotropy are the two main evolutionary hypotheses for homosexuality.. there does not appear to be a consensus about whether either is true"}} – they're both largely ruled out by GWAS, especially exclusive male homosexuality. There's still plausibility for antagonistic maintenance of the trait through other mechanisms such as however. |
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::I'm not saying they should not be covered, the does indeed refer to both of them. I just think the coverage should be trimmed down, similar to the extent it is covered in that review. |
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::] (]) 04:50, 24 May 2024 (UTC) |
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Comment; the problem being that for example, there is a causes of trans sexuality article, but there is no central place for causes of sexual orientation in total, so it kind of lacks cohesion. But we can just move it down. ] (]) 05:39, 9 October 2020 (UTC) |
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:::{{tq|As for not being able to find reviews, they are better reviewed and criticized in text books. ... I'm not saying they should not be covered, the Bailey review does indeed refer to both of them.}} Was not aware {{strikethrough|of}} the Bailey article is a review. What textbooks refer to them? I certainly agree that reviews would be better than the primary sources cited for the reasons that you've cited. Are there reviews of GWAS research that contradicts the kin selection and antagonistic pleiotropy hypotheses? -- ] (]) 13:29, 24 May 2024 (UTC) |
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::::{{u|CommonKnowledgeCreator}}, alongside the Bailey review you could refer to textbook with various chapters, or , or ] also has some discussion of evolutionary hypotheses. There are more I can find if need be. Hope this helps! ] (]) 03:41, 13 June 2024 (UTC) |
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:::::I'm sure that textbook would be great. Unfortunately, it has a paywall so I cannot access it. -- ] (]) 11:35, 13 June 2024 (UTC) |
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::::::{{u|CommonKnowledgeCreator}} – oh, just start using , which you qualify for. You get access to paywalled content from all the leading publishers. Access to the Springer collection is probably the best, as you get all their papers ''and'' books. I recommend using the 'access collection' button on each publisher and then conducting your search, rather than using the search box at the top of Misplaced Pages Library (which accesses papers in a clunky format, with poor search capability). Hope this helps. ] (]) 09:31, 14 June 2024 (UTC) |
There are 3 undated Citation needed tags. One of them is from March 2007, so if someone more familiar can take a look and see whether they are still needed. Thanks Slywriter (talk) 05:08, 26 March 2023 (UTC)
PMCID: PMC10757681 DOI: 10.7759/cureus.51346
The disparity in sexual identity in monozygous twins may relate to the time of splitting of the zygote– twins resulting from splitting on or before day 5 after fertilisation are free to develop their own sexual identity; twins splitting after day five have the same identity.
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This article was the subject of a Wiki Education Foundation-supported course assignment, between 24 January 2022 and 13 May 2022. Further details are available on the course page. Student editor(s): C.ler2022 (article contribs). Peer reviewers: Bcruz-cisneros.