Actually, most of us are "bisexual" in the sense that we're capable of sex with men and women, even if we don't ever actually do it. Most of us prefer heterosexual relationships, but a small percentage of people in every culture prefer homosexual relationships. Truly bisexual people are capable of having fulfilling intimate relationships with people of both sexes. Some people think this could be an advantage in finding a life-mate.
As to the "why" of it, same-sex relationships can satisfy emotional needs for both men and women without risking pregnancy. (In some cultures, lesbian acts aren't even considered to be "sex".)
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Answer (from a bisexual)
Before I answer directly, let me clear some things up so you really understand what I'm saying in the answer.
Clarification-
Bisexual does not mean "attraction to only male and female" anymore than Gay men are always happy or Lesbians come from the Isle of Lesbos. Once, in the dark days of psychiatry, that's what it meant--- but it's been reclaimed by the people it was once used to "diagnose" and torture. Us. Now it means an intrinsic desire for other humans, in all their many combinations of sexes and genders, simplified as "an attraction to those like myself" and "an attraction to those different than myself". Bisexuals are people with fluid sexuality and unlike monosexuals (hetero and homosexuals, for the most part, although there are other types) who have rigid sexuality. Just as Heterosexuals could never feel comfortable having a Homosexual relationship and Homosexuals a Heterosexual one and both may have problem even imagining the opposite situation--- Bisexuals cannot imagine not being attracted to other human beings in general. Our attraction is not limited by sex or gender (the two biggies in "bi" are not male and female, as I've said. If you encounter a bi that says this they may be new to bisexual culture, trying to avoid a long explanation like this one or are speaking of preferences. In popular culture the male/female thing is a misconception based on the 'fast and sloppy' description of bisexual behavior-- so many people "just out of the closet" may not be familiar with anything but this ugly stereotype and try to emulate it. It's much like young homosexuals acting "tv gay" before they relax and embrace their homosexuality.). It's as simple as that. We find other human beings sexually exciting and beautiful. Bisexuality is a stable sexuality. We are fully capable of being monogamous. We do not need "both women and men" at the same time to be happy. We are not confused. We are not half gay/ half straight. We're not sitting on the fence. We are simply bisexuals.
It is really sweet that the original answer mentioned that some people consider bisexuality a benefit to relationships. I would like to meet these people! The unfortunate truth is that though we are (percentage-wise) the largest chunk of the GLBTIAQ, we also experience a disturbing amount of biphobia from that direction. Some organizations within the "Alphabet Soup" community deny that bisexuals in fact, exist, and forbid us to enter their social or sporting events. We are degraded, stripped and inspected (this actually happened to Bisexual players during a softball tournament), demands are made on us to prove our "queerness". There were even rumblings about removing the "B" from the "Soup", despite Bisexuals being heavily involved with the Gay Rights movement since Stonewall. That rears its head again from time to time. (on a personal note-- Just before college graduation, my best friend of many years, a gay man, told me point blank that bisexuals did not exist and I had best choose if I wanted to be homo or het because he was tired of me being 'halfway out'. That hurt me in ways I can't even describe and destroyed our friendship.) In combination with the violent homophobia, fetishization and historical erasure from heterosexuals, this paints a bleak portrait for romance options if you're bisexual. It is not, as Woody Allen said, about having double the choices on Saturday night. Rather it's about facing twice the rejection and the stigma of potentially being unwelcome everywhere.
This is why many Bisexuals (along with other sexually fluid people) tend to form our own tight knit support groups. We could once count the Genderqueer, Transgendered and Transsexual among our closest allies, because they too cross barriers that others see as insurmountable. This has changed in recent years with inflammatory studies published about bisexuals and our supposed "reinforcing" of the "Gender-binary"-- it is often ignored that these studies were published by people with an anti-bisexual agenda. In the wake of them, we are left arguing with the people we could once count on the most as they try to force an erroneous definition (that we are attracted to ONLY male and female, and uphold that strangely rigid idea in our communities) from those biased studies on our sexuality and demand that we abandon bisexual as an identity altogether (despite it's rich history and political power) and make a new one that is less "cis-sexist" even though, in reality, (as I said above) the things reflected by those prejudiced studies aren't true.
The answer, at last!--
The simple answer is, in light of everything I just said, we are the way we are because we can't be any other way. Denying your very natural attraction to other human beings is a pretty quick ticket to the funny farm (or an early grave) and only an idiot would choose to have this kind of BS shoved down their throat constantly. (I used to wish all the time as a teenager and young adult for exclusively monosexual feelings-- but no amount of prayer, denial, or driving myself batshit changed anything. All it did was make me extremely nervous and depressed. Now that I'm older I decided that no amount of "passing" in either group could ever make denying who I am okay. I do not want to be with anyone who doesn't accept me for what I am.) Otherwise there are varying scientific explanations involving fetus' genetics and prenatal hormones in the mother (not the fetus itself) working in concert. These point to bisexuals being born bisexual.
Because they have too much love to share with just the opposite sex!! ;)
90% of are Bisexual.
Nobody turns bisexual. If a woman is bisexual, she has always been bisexual.
There are many people all over the world who are bisexual.
In general, no. Some people find it easier to be bisexual, and some gay people often identify as bisexual to test the waters, so to speak. However, this has resulted in a phenomenon called bisexual erasure. People are more likely to believe that, no matter what a bisexual person says, they must prefer one gender or the other, which can cause great frustration for the bisexual community.
Being bisexual does not mean that someone needs to have sex with people of both genders. It merely means that they are attracted to people of both genders. So it is possible for someone to "be enough" for a bisexual.
It can be if you let it be. Typically people start out as bisexual and then feel more comfortable about there sexual orientation.
NO i dont, i am bi
i am not bisexual but personally i can still be friends with people that are bisexual because i dont care what they do because it's there life and i feel that they are people to.
Yes, of course.
On the planet Earth
No. You are only bisexual if you are sexually attracted to people of both genders.
most of them are... just like straight people or gay people