TLDR: The idea that the gender which you prefer to have sex with matters in who you are personally is modern. Heterosexuality and homosexuality are modern concepts that have not always existed. They are not genetic conditions.
And, neither is poly. One is not born a poly or a mono or any other relationship variation.
I agree that the concept of sexual identity is a social construct. Before we decided we wanted to have names for a man who shags other men exclusively and seems to have no interest in females at all... he was just Fred (or Ughlugh, depending on how far back we are going).
Currently I am not aware of any single genetic link being identified as the culprit for sexual orientation. However, with what *is* known about how genetics affect behavioral tendencies it is reasonable to presume that there is a genetic link to sexual orientation, obsessive/compulsive, and any other social behavior. Not as the determining factor necessarily, but certainly a factor.
I was reading a book on behavioral evolution (I think, it was a while ago) and he explained it in what I thought was an interesting way. That our genetics is not a floor plan for who we will be as we develop, however they do suggest a tendency toward a certain type of behavior within a range. That this "gay gene", for example, doesn't decide for someone what their sexual orientation will be, but it would suggest that no matter the persons environment as they develop they will fall somewhere within a certain range. That genetics shouldn't be thought of as an arrow pointing toward a particular behavior but as a probable range on a spectrum of behavior.
That being said, even the most fundamental of our evolutionary behaviors seem to be trainable. The fact that we flinch at loud noises is an example I like to use. Humans flinch at unexpected loud noises for good reason, we tend to draw in our extremities for safety, we flex our bodies to prepare for impact, our adrenaline gets a bump in case we need to launch into action, it's a survival mechanism that is demonstrably "hard-wired". However, even such a primal and deep routed instinct as this can simply be trained out of us. Granted, I suspect some people would take much longer to learn to stop flinching (immersion therapy is what I'm imagining), and some people might never stop flinching... but most will simply be desensitized and not respond to the loud noises anymore.
Humans are so flexible that I wonder how much this genetic range potential could really affect us. Not that it matters necessarily, but it is a fun concept to think about and I hope geneticists can bring us a solid answer some day.
nycindie said:
"But I've always wondered why I couldn't have two boyfriends ever since I was in Kindergarten!" that doesn't mean jack shit about your biology or brain chemistry. We all have the potential for many different life choices and where we end up basically has to do with cultural and familial conditioning, personal preferences, how our life experiences have affected us, and opportunity.
I think that the error is in trying to place some kind of "natural" classification on something like monogamy versus polyamory. Personally I don't find these classifications to be very descriptive. What I *do* find to be descriptive are concepts like "controlling", "insecure", "independent", etc.
If the "genetics represent a potential range" concept is true, that would suggest that a person is likely to be controlling of other people in his surrounding within a certain range. Where they fall within this range would depend on their environment and other factors you listed.
nycindie said:
In Western culture, we have the luxury of questioning everything and I really think most people make shit up to justify their choices.
This is the rub.
No matter the degree to which genetics and environment shape who we are (chicken or egg, nature or nurture), getting hung up on being able to properly label ourselves is just masturbation. Getting caught up with what we were "meant to be" is not productive and we will be better of examining who we are, who we want to be, and how we plan on maximizing our happiness.