The way to understand homosexuality is through understanding human sexuality. However, human sexuality is not the same as heterosexuality, beacuse biological gender, gender identity, gender orientation and gender roles develop independently and sometimes in conflict with each other, so any version can and does exist.
A variation of this is when a person's gender identity is the same as his or her biological gender, but he or she feels affection for the same gender. What a society considers to be the norm, what it tolerates or whether it takes a dim view - or rather what it persecutes or punishes - can not be interpreted from a human nature standpoint, but rather from historical-social contexts. The reason for the stressful nature of discussion around male homosexuality is that it has been the most troubling for religious and secular powers throughout history.
Anthropological studies prove that in many Natural people, between warriors, or between men and the boys raised by them, it is not simply allowed, but required to have a homosexual relationship, to which is attributed great ritual significance (Szendi, 2016; Greenberg, 1988). This is usually accompanied by the fact that women are considered dangerous, unclean, or at least inferior. This was the case with the ancient Greeks, and in the early stages of feudalism, where woman served for the purpose of reproduction, while true love was woven between men. Louis-Georges Tin in his book, "The Invention of Heterosexual Culture" calls male-centric societies, in which - in the modern sense - passionate love was not necessarily associated with sexuality, was born between men in homosexual societies. Persecution of homosexuality started in the 12th-13th centuries and the Christian church played a significant role in this. The heterosexual culture that focuses on male-female love began to strengthen during the time of the Renaissance. The concept of homosexuality that is still haunted by medicine and psychiatry - according to which it is seen as an illness - became dominant in the 19th century.
The definition of homosexuality is not straightforward, since male love or male prostitution, that is in fashion even today in Asia or Africa, or homosexual activity in prisons, is not the same as homosexuality that occurs in the context of specific neurobiological development. Moreover, even within this, questions arise as to the intensity of homoerotic affection, because like all human traits there is a bell curve distribution which can be observed. But then who is homosexual? Only those who have homosexual relationships or who have felt such affection, which represents 16-21% of men (Hines, 2011), or even those who have erotic affection behind their sometimes excessive enthusiasm towards same-sex people? This dilemma highlights the fact that society wants to see human sexuality in black and white, while in reality there are many different shades, and many people - because of prejudice - struggle to recognize and accept their gender identity and affections.
The roots of the problem
The whole problem arises from three fundamental mistakes of western thinking. One is that any departure from "normal" sexuality for reproductive purposes is a deviance or disease. Another mistake is that sexual characteristics are only the result of upbringing.
The third is that in the western world, one's sexuality is determined by one's gender. In the spirit of the first mistake "sexual aberrations" have been legally persecuted for centuries. In the name of the second mistake, psychiatry considered it a disease until the 1970s and wanted to "treat" homosexuality by barbaric means. In the 1970s, fake sexologist John Money elevated the notion to the ranks of science that gender identity and gender roles are shaped by education (Szendi, 2016). Soon it became apparent, that boys who had been medically altered to girls during their infancy began to feel like men in their adulthood.
The omnipotence of the concept of upbringing was ultimately disproved by the case of boys raised as girls in the secluded villages of Dominica in the 1970s. These boys had partial sex hormone insensitivity, so they were considered to be girls at birth, but at puberty they became masculine because of the sudden increase in testosterone production, and despite how they had been raised, they started to act as men (Imperato-McGinley et al., 1974).
Several studies have tracked the sexual development of children raised by homosexual or transgender parents, but found no difference compared to children raised by heterosexual parents (Green, 1978; Anderssen et al., 2002).
The third mistake was avoided by many people. Namely, that sex is a complex thing, and other dimensions of sexuality can be independent from biological sex. For the Navajo, for example, there are five genders; and there are traditionally four genders kept count of in Thailand (Szendi, 2016). These people acknowledge the gender specificities that contradict biological sex.
Homosexuality and evolution
The 'unnatural' nature of homosexuality is usually called a disorder by the fake scientific argument that it does not lead to reproduction. However the evolutionary capability of an individual is determined not only by their reproductive success, but also by the prevalence of their genes in the succeeding generation. This way, if someone is childless, but let's say helps in the raising of their sibling's children, then these children's subsequent reproduction raises their own overall capability, as the nephews and nieces carry 25% of their genes (Wilson, 1975).
The fact that some sort of benefit had to arise from boys being homosexual is also confirmed by the birth order theory. According to Ray Blanchard's studies (Blanchard, 1997) a boy is more likely to become homosexual, depending on the more boys he was born after. The probability of being homosexual grows with each older sibling by approximately 30%. The researchers estimated that the seventh, youngest brother has a 3.7% chance of being homosexual (Sanders et al., 2015). The fact that this is clearly a biological effect proves that this rule applies even if educational effects are excluded, that is, the boy grows up not in his original family (Bogaert, 2006). According to the theory, during repeated pregnancies with boys, antibodies are being produced in the mother against the H-Y antigen, which is the collective name for the specific groups of cells on the surface of the male fetus' cells, and the increasing immune response makes it more likely for the later born child to be homosexual. Although aborted male fetuses belong in the order of siblings as well, families with more male children are becoming rarer.
Despite this, the ratio of male homosexuals is 6-10% (Hines, 2011), which means that homosexuality can develop in other ways as well (see later).
However, the fact that several mechanisms that create homosexuality have evolved during evolution proves that homosexuality is part of the evolutionary plan and cannot be considered as some sort of "scrap." The fact that this is a concerted "plan" proves that the homosexual man's mother and her siblings are characterized by increased fertility (Camperio et al., 2012). A possible interpretation of the "plan" is that after the birth of the umpteenth boy, homosexual boys should be born who are not rivals, but helpers, in obtaining a limited number of women. This is the theory of the homosexual alliance, which is supported by the physical-spiritual friendship between warriors.
Homosexuality in the animal world
The "unnatural" argument is deeply undermined by the fact to date up to 450 species of the animal world have been observed in homosexual behavior (Bagemihl, 2000). Animal homosexuality generally has evolutionary benefits. In bonobo chimpanzees, the immediate ancestor of man, both females and males often engage in homosexual activities, which strengthens group cohesion and reduces internal conflict. Hawaiian albatross females often form a lifelong couple and hatch their eggs together. Fertilization naturally occurs in occasional relationships. Homosexuality between male lions in the pack, or between bottlenose dolphins, strengthens the alliance between males. In the animal world, homosexual behavior is often motivated by attachment, association, tension reduction, or preparation for heterosexual relationships (Bailey and Zuk, 2009).
The hormonal theory
The birth order does not explain the relatively high proportion - at 6-10% - of homosexual men in the population. Therefore, other explanations have emerged.
The multiplicity of human sexuality is best understood by the effect of sex hormones on the fetal brain. The research is made difficult by the fact that only indirect measurements are available to us. Brain researcher Simon LeVay has proven that by the size of certain brain areas it can be ascertained in blind tests whether it is the brain of a hetero- or homosexual man (LeVay, 1994). Since the size of the nucleus that influences sexual behavior in homosexual men is similar to that of women, it has long been believed that male homosexuality is caused by lower fetal testosterone effects. This was also supported by the fact that the imaginary rotation of objects in space is testosterone dependent, and that both women and homosexual men performed worse in this (Peters et al. 2007).
An interesting study looked at the effects of men's fragrance on brain function, where a certain area of the brain of homosexual men and heterosexual women became equally active, while heterosexual men did not respond to the scent (Bao and Swaab, 2011). The 2:4 ratio of the fingers, that is the ratio of the length of the index finger to the length of the ring finger suggest a lower testosterone effect. Since during the fetal life estrogen grows the index finger, while testosterone grows the ring finger, women generally have a longer index finger than their ring finger, and vice versa for men. Since homosexuals have a masculine finger ratio (typically 0.96-0.97) but heterosexuals have an even lower rate (that is, an even longer ring finger) this underpinned the theory of lower testosterone effects in the development of homosexuality (Collaer et al., 2007).
Today however, this idea seems to have been overturned, and many researchers assume a normal or extra testosterone effect behind male homosexuality. There is more indirect evidence of high testosterone activity. Since the size of the penis is related to the fetal testosterone levels and according to measurements homosexuals have on average a larger penis, this indicates that they are more likely to have greater testosterone exposure than heterosexuals. Behaviors of homosexual men - increased polygamous tendency and increased sex drive - also indicate higher levels of testosterone. The issue is complicated by the fact that the levels of sex hormones change from time to time during fetal life, the brain itself produces sex hormones, and the different hormone sensitivity can lead to differences in sexual orientation even with identical hormone levels (Breedlove, 2017).
The genetic theory of homosexuality
The genetic determination of homosexuality comes up again and again, which is not surprising, since in the end genes regulate everything from hormone levels, through hormone sensitivity, to the size of brain nuclei. Two chromosome areas were suspected: one can be found on the X chromosome, and according to researchers, it determines sexual orientation (Sanders et al., 2017). The inheritance associated with the X chromosome is confirmed by the fact that there are more homosexual men in the maternal lineage of homosexual men then in the paternal.
However, the direct genetic determinants of homosexuality are contradicted by the fact that in the case of identical twin pairs who were genetically identical, if one twin was homosexual, only 20% of twin couples were homosexual as well (Bailey et al., 2000). One explanation for this is that homosexuality is a biological urge with variable intensity, and one member of the twin couple may be affected by amplifying effects, while the other receives stronger support for heterosexual orientation. Another explanation is the epigenetic effect, which means that intra-uterine biochemical effects can turn genes on and off, for example those that are responsible for testosterone sensitivity, and this determines later sexual orientation (Rice et al., 2012).
The hormonal, genetic and epigenetic explanations are all obviously able to describe the ways in which homosexuality has developed, but to this day they are independent lines of research.
Homosexuality and environmental impact
The "directionality" of the development of homosexuality is also supported by the observation that, for example after World War II, the proportion of male homosexuals increased (Dörner et al., 1980). This is clearly caused by stress, as other studies suggest that more severe stress in the mother and fetus during the first trimester of pregnancy promotes homosexuality in male offspring (Ellis and Cole-Harding, 2001), while in those that were born during the Dutch war famine of 1944-45 did not find such an effect (de Rooij et al., 2009).
Many people are worried about the potential effect of taking drugs during pregnancy, but out of 19 types of drugs, only the use of thyroid hormone replacement or amphetamine-containing tablets in the first trimester increased the likelihood of developing lesbianism in female offspring (Ellis and Hellberg, 2005). However according to a newer study, hypothyroidism during pregnancy significantly increased the incidence of homosexuality in offspring, independent of hormone replacement, both in boys and girls (Sabuncuoglu, 2015). Since the majority of mothers did not take hormone replacement, the thyroid dysfunction explains the result, according to the author, not the hormone replacement. Thyroid hormones play an essential role in brain development, and even their subclinical deficiency can cause disturbance in critical stages of brain development.
We do not yet know exactly how homosexuality develops, but it is certain that the issue is decided at the fetal stage, and that education will have no significant influence on gender. Homosexuality, like other forms of human sexuality, is an equal variant of human sexuality, and prosecuting or discriminating against it in the name of the heterosexual majority shows a disregard for fundamental human rights.
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