Whether biological factors or environmental factors cause sexual orientation is a very controversial subject. Through scientific studies one can come to the conclusion that sexual orientation, more specifically homosexuality, is primarily caused by genetic or biological factors. The discovery of genes that result in homosexuality in male fruit flies, genes that are present in more than two thirds of homosexual men, and neuroanatomical differences between heterosexual and straight men are the basis of this conclusion. All of this evidence must be examined in a critical and scientific fashion in order to come to a more definitive conclusion as to what causes homosexuality. .
Is sexual orientation a trait that is learned through life experience or one that is determined genetically?.
Sexual orientation is generally one of three main categories: heterosexual, homosexual, or bisexual. A heterosexual person is one who is attracted to members of the opposite sex. A homosexual is someone that is attracted to members of the same sex. And, a bisexual person is one that is attracted to members of both sexes. There are other breakdowns when looking at sexual orientation; some people consider themselves to be transgendered (a woman trapped in a man's body or vice versa). But, in general, heterosexual, homosexual, and bisexual are the three main categories of sexual orientation.
When someone says that something, in this case sexual orientation, is learned, he or she means that certain experiences in a person's life taught that person which gender they should be attracted to. On the other hand when someone says that sexual orientation is biological or genetic, he or she means that sexual preference is determined before you're even born; it is determined by the genes you get from your mother or father, just like eye, hair, and skin color.
Examine the Evidence.
The first finding of any evidence that homosexuality may be biological occurred in 1991 when Simon LeVay found neuroanatomic differences between homosexual and heterosexual men (neurolinguistic).