Beefbisquick.. I assume your not much into science as what you replied to my comment is nothing more then opinion. It has been in fact shown that in the genetic mapping looking at those who are homosexuals their are RNA differences and Chromosome sub structure that are not the norm. Normal being the understood majority within a defined group ie in humans the norm is that gentic hetero women and general heterol men attract and reproduce to continue the species. Now the homosexual beings which are not the norm or normal sexuality for our species are the abnormally. So for you to deny so many scientific studies and genetic mutation Gnome mapping is laughable.
You then ask a question which in reality makes no sense as you ask about one definition while trying to insinuate the world has a single meaning.Everything more or less happens in nature as in if your using it to define environment which your asking but your impliment is in regards to a populous question as in human nature or ie tendencies which then is completely different. Yes in the "Environment of Nature which is Earth" homosexuality happens. Now has for it being a tendency of human nature its is not normal or the percentage of homosexuals would have to be much higher which it is not.
Now I could ask just as ridiculous question then such a " Well if it is natural and meant to be then why can't 2 males or 2 female humans reproduce to further their geneitc traits to the world?" That's also part of the natural selection process. Animals, mammals, and fish lineage will allow the most important traits dictate the species further existence. Since the homosexual life is no condusive to the speices survival it has not been given the option to work anyway but as it was originally intended to. If people are gay and that's how they are happy that's fine, but a few things just do not change basic scientific facts your chromosomes determine your sex so he's will always be he's and shes will always be she's. It gets pretty deep with the basics of defining the epi marks or "switches" that activate or deactivate traits which if your familiar with epigentics it makes quick sense.
A quick way to say it is kind of like if a mother has this trait and when she is pregnent the epimark traits that regulate the genetic production of say testosterone which she had blocked as a female fetus when she was born flip the epimarks in her new forming male fetus resulting in low levels which now are being ignored by this male child then basically the new embrayo is told to not worry about testosterone needs or production which all the estrogen to be dominant activating female trait tendencies. And then it is the opposite in homosexual women. So the idea that sexuality is not genetically influenced is just false and non proven while this branch of logic has data proven it.
First of all, most of that didn't make sense to me, but I'll respond to the parts that did.
I never made the claim that DNA didn't affect homosexuality. I rejected the statement that G.I.A. made that it's
only caused by a genetic defect. You are arguing against something I never said, and in fact if you read this thread in it's entirety I posted links to several scientific studies, that indeed mention epi-marks as one of the causes. If you actually read
before commenting, you'd also see that
many other factors also influence homosexuality. All of which have strong supporting evidence gathered from scientific studies.
I don't need a lesson in basic evolutionary principles either. I've already posted links to studies that show evolutionary benefits to homosexuality, so your statement about homosexuality not being conducive to mammalian and fish species survivability, is pretty short sighted. For example having a homosexual child can dramatically affect the sex of your
next child. It could be argued that without homosexuality there would either be too many women or not enough, we don't know, but that doesn't sound very good for the sustainability of the species, does it?
INCOMING KNOWLEDGE BOMB!
A well-known theorist suggests that biology influences childrens temperaments and their preferences for sex-atypical activities and peers, leading them to feel different others of their sex. They later become attracted to what they are different from.
[Exotic becomes erotic theory] proposes that biological variables, such as genes, prenatal hormones, and brain neuroanatomy, do not code for sexual orientation per se but for childhood temperaments that influence a childs preferences for sex-typical or sex-atypical activities and peers. These preferences lead children to feel different from opposite- or same-sex peersto perceive them as dissimilar, unfamiliar, and exotic. This in turn produced heightened nonspecific autonomic arousal that subsequently gets eroticized to that same class of dissimilar peers: Exotic becomes erotic.
Bem, Daryl J., PhD. (1996) Exotic Becomes Erotic: A Developmental Theory of Sexual Orientation. Psychological Review. Vol. 103. No. 2, 320-335.
Commentary from scientific literature shows that evidence is lacking for a simple genetic or biological explanation of homosexuality. Evidence does not support the hypothesis of a gay gene.
Its important to stress what I didnt find. I did not prove that homosexuality is genetic, or find a genetic cause for being gay. I didnt show that gay men are born that way, the most common mistake people make in interpreting my work. Nor did I locate a gay center in the brain.
LeVay, Simon, PhD. (March 1994). Sexual Brain. Discover.
There is no one gay gene. Sexual orientation is a complex trait, so its not surprising that we found several DNA regions involved in its expression.
Our best guess is that multiple genes, potentially interacting with environmental influences, explain differences in sexual orientation.
Our study helps to establish that genes play an important role in determining whether a man is gay or heterosexual.
Mustanski, Brian S., PhD. (Jan. 27, 2005). University of Illinois news release on A Genomewide Scan of Male Sexual Orientation. Human Genetics, vol. 116.
While some authors have speculated about the existence of genes for homosexuality, genes in themselves cannot directly specify any behavior or cognitive schema. Instead, genes direct a particular pattern of RNA synthesis which in turn specifies the production of a particular protein.
There are necessarily many intervening pathways between a gene and a specific behavior and even more intervening variables between a gene and a pattern that involves both thinking and behaving.
The term homosexual gene is, therefore, without meaning, unless one proposes that a particular gene, perhaps through a hormonal mechanism, organizes the brain specifically to support a homosexual orientation.
Byne, William, MD, PhD. (1995). Science and Belief: Psychobiological Research on Sexual Orientation. Journal of Homosexuality, vol. 28.
It is possible that hormones could affect sexuality through their impact on gender-typical traits. Some recent findings suggest this could be true in women.
Girls with congenital adrenal hyperplasia, for example, are exposed to high levels of adrenal androgens [hormones] prenatally. Some research indicates that postnatally they show greater aggression, enhanced (i.e. masculine) visuospatial abilities, more masculine occupational preferences, and an increased rate of bisexual or homosexual sexual orientation in fantasy and/or behavior.
Alexander, Gerianne M. (2003). An Evolutionary Perspective of Sex-Typed Toy Preferences: Pink, Blue, and the Brain. Archives of Sexual Behavior, vol. 32, No 1.
But it would be inaccurate to believe that hormones have any direct link to adult sexual interests or orientation.
Studies of men and women who experienced prenatal defects in hormone metabolism have not found a concurrent increase in homosexual behavior.
Overall, the data do not support a causal connection between hormones and human sexual orientation.
Banks, Amy, MD, and Gartrell, Nanette K., MD. (1995). Hormones and Sexual Orientation: A Questionable Link. Journal of Homosexuality, vol. 28 (3-4).
The dominant paradigm that generates support for biological theories of sexual orientation has profound conceptual flaws
The current consensus opinion is that no causal relationship exists between adult hormonal status and sexual orientation.
Currently, the major impetus for speculation and research concerning an endocrinological basis for sexual orientation derives from animal studies
Such studies have established the prenatal hormonal hypothesis for sexual differentiation of the rodent brain
The problems inherent in using studies of mating behaviors in rodents
to formulate a theory of sexual orientation in humans are immense
Thus, the prenatal hormonal hypothesis as derived from animal studies cannot account for exclusively homosexual behavior in men with normal male genitalia.
Byne, William, MD, PhD. (1995). Science and Belief: Psychobiological Research on Sexual Orientation. Journal of Homosexuality, vol. 28 (2).
Birth order has been investigated as a possible factor influencing homosexuality but without conclusive results.
The number of biological older brothers, including those not reared with the participant (but not the number of nonbiological older brothers), increases the probability of homosexuality in men. These results provide evidence that a prenatal mechanism, and not social and/or rearing factors, affects mens sexual orientation development
If rearing or social factors associated with older male siblings underlies the fraternal birth-order effect, then the number of nonbiological older brothers should predict mens sexual orientation, but they do not
If rearing or social factors underlie the fraternal birth-order effect, the number of biological older brothers with who they were not reared should not predict mens sexual orientation because they should have no impact on the sociosexual environment of their younger brothers. Yet, these brothers do predict mens sexual orientation just as the number of biological older brothers with whom they were reared.
These results support a prenatal [before birth] origin to sexual orientation development in men and indicate that the fraternal birth-order effect is probably the result of a maternal memory for male gestations or births.
Bogaert, Anthony, PhD. (July 11, 2006). Biological Versus Nonbiological Older Brothers and Mens Sexual Orientation. The Proceedings of the National Academy of Sciences, 103.
In diverse samples and independent replications, homosexual men are found to have a greater number of older brothers than heterosexual men
[This] certainly does not provide a universal hypothesis for the origins of homosexuality since the majority of homosexual men do have this history and do not fit in this model.
The hypothesis advanced in the above studies is that the late birth order, with more male siblings born earlier, could lead to a progressive immune response of the mother to androgens and/or Y-linked [male specific]
antigens which, by maternal transfer of these immune antibodies to the fetus, could impair brain masculinization of the fetus. However, why this mechanism would selectively impair only certain androgen-dependent processes, such as the brain programming, and not other, like formation of the genitalia, is not explained by this hypothesis, and not even addressed by the proponents. Nor does this theory explain why the majority of boys late in birth order do not become homosexual, even if the elder brother is homosexual
The biological explanation advanced for the fraternal birth order hypothesis lacks any experimental support.
Gooren, Louis, PhD, MD. (Nov. 2006). The Biology of Human Psychosexual Differentiation. Hormones and Behavior, 2006.
Research on brain structure suggests a possible link between homosexuality and less masculinized brains.
But the research does not demonstrate that the less masculine brain structure itself is the direct cause of the homosexual orientation. It is, however, conceivable that a male with a less masculinized brain might develop gender-atypical traits, leading to gender incongruity. This might be especially true if those around him accentuate his differences.
A growing body of empirical literature suggests that the brains of gay males are less masculinized than those of heterosexual males, reflected in visual-spatial task performance a measure of cerebral masculinization and one in which heterosexual males usually surpass females.
Several studies report that the cognitive performance of gay males is more typical of heterosexual females than heterosexual males.
Furthermore, the brain waves of gay males while performing verbal and spatial tasks are more similar to heterosexual females than males or significantly different from both.
Cohen, Kenneth M., PhD. (2002). Relationships Among Childhood Sex-Atypical Behavior, Spatial Ability, Handedness, and Sexual Orientation in Men. Archives of Sexual Behavior, vol. 31, No. 1.
From the APA:
There is no consensus among scientists about the exact reasons that an individual develops a heterosexual, bisexual, gay, or lesbian orientation. Although much research has examined the possible genetic, hormonal, developmental, social, and cultural influences on sexual orientation, no findings have emerged that permit scientists to conclude that sexual orientation is determined by any particular factor or factors. Many think that nature and nurture both play complex roles; most people experience little or no sense of choice about their sexual orientation.