I'm awfully sorry, 16B, but I don't see how any of the articles you've shown indicate that homosexuality is unnatural.
Article 1:
Truthout
Researchers have also shown that increasing numbers of male western gulls hatched from eggs exposed to DDT attempt to mate with each other.
Doesn't explain why homosexuality existed BEFORE exposure to DDT. DDT is a modern chemical, so how does this explain homosexuality prior to human exposure to such chemicals? You've also made the disingenuous argument of linking human and animal sexuality when there are clear and undeniable differences between the two, especially in terms of reproduction. The male western gulls referred to in this article are more likely to be affected by DDTs because they are born to an avian reproductive system which has more chance of disruption than a mammalian reproductive system. Once an egg is fertilised in a bird, it is on its own; no placenta to remove any nasty chamicals. What goes in the albumen stays in it.
Article 2:
New Evidence for Biological Influence on Gender
... then a boy with a brain that had been feminized in utero by an environmental toxin such as atrazine would be at particular risk to establish a weak masculine gender identity and thus to develop homosexual attractions in adulthood.
This is a badly-put argument. Sexuality and masculinity are very distinct. I am NOT effeminate. Masculine gender identity? What the hell is that? Methinks the journalist is not familiar with the differences between sex, gender, and sexuality, and feels he can fudge the three of them to make his point stand. And, again, there is no explanation for how homosexuality can have existed before humans were exposed to environmental toxins.
That earlier study concluded that male homosexuals are about one-third (31%) more likely than heterosexuals to be left-handed, while lesbians are almost twice as likely (91%) to be left-handed as heterosexual women. LaLumiere believes this indicates that homosexuality ... has a neuro-developmental basis tracing back to "disruptive events causing developmental instability" which have modified sexual differentiation of the brain, "perhaps through hormonal or immunological mechanisms." Homosexuality is generally understood to result from a combination of psychological, biological, and social factors. In those homosexuals whose condition had a primarily biological rather than a psycho-social foundation, homosexuality would be, like left-handedness, a "biological developmental error."
He then goes on to list conditions associated with left-handedness. Well, I don't hear anybody claiming that left-handedness is abnormal or even abhorrent. This pseudo-scientific organisation does not note that we stopped trying to "cure" left-handedness in the 1800s because it is impossible.
Additionally, the author has failed to note the growing belief in a genetic case for homosexuality. The later claim of higher pathology among homosexuals does not take into account the fact that the society in which the study took place (USA) has greater social difficulty with accepting homosexuality. In a society where you're constantly told, succintly or overtly, that being gay is evil, I'm hardly surprised that some gay folks develop pathological diffculties. I suspect that Canada, a mere border crossing away, would have a lower rate of pathology. Whose fault? No-one's. Different societies evolve in different ways.
Article 3: BBC News Website, 10 July 2004,
Pollution 'changes sex of fish'
I am not a fish. I am a man. This article has nothing to do with sexuality.
You will NOT convince me that my sexuality is an unnatural any more than you will convince me that left-handedness is unnatural. Even the gay-hating NARTH organisation says in its article that it believes homosexuality occurs due to biological and immunological changes. Ergo, it happens - gasp - naturally. And since Plato, Edward II, James I of England, Oscar Wilde and Alan Turing - among other luminaries - were homosexuals BEFORE any of your chemical arguments applied, I do not see how you can prove your case at all.