Bisexuality

Bisexuality involves romantic attraction, sexual attraction, or sexual behavior directed at more than one gender, or attraction that is not constrained by sex or gender. The term first appeared in the 19th century within early sexology, coined in German by Richard von Krafft-Ebing in his work *Psychopathia Sexualis*, and was introduced into English by Charles Gilbert Chaddock in his 1892 translation. It originally described individuals who experienced both homosexual and heterosexual attraction. The label "bisexual," or "bi," was reclaimed as a sexual orientation identity in the 1960s. Since then, the bisexual community has defined it in numerous ways: as attraction regardless of sex or gender; as attraction that goes beyond the gender and sexual orientation binary; as attraction to men and women; as attraction to more than one gender or sex; as attraction to people of similar or same genders as well as different or other genders; and as attraction where gender is an irrelevant factor.

Scientists do not know exactly what determines sexual orientation, but they theorize it results from a complex mix of genetic, hormonal, and environmental influences, and they do not view it as a choice. While no single theory on the cause of sexual orientation has widespread support, scientists favor biologically based explanations. There is considerably more evidence for nonsocial, biological causes than social ones, especially for males. Bisexuality has been observed in many human societies throughout recorded history, as well as elsewhere in the animal kingdom.

Definitions of bisexuality vary. The American Institute of Bisexuality describes it as an umbrella term covering a wide range of identities, terms, attractions, and behaviors that fit the scientific definition—it is a general, inclusive term encompassing all sexes and genders. This does not mean bi people are attracted to everyone, only that their attractions are not limited by sex or gender. Activist Robyn Ochs defines it as the potential to be attracted—romantically and/or sexually—to more than one sex and/or gender, not necessarily at the same time, in the same way, or to the same degree.

The American Psychological Association states that sexual orientation exists on a continuum; someone does not have to be exclusively homosexual or heterosexual but can feel varying degrees of both. Orientation develops across a lifetime, with different people realizing at different points that they are heterosexual, bisexual, or homosexual. Attraction for bisexuals can take many forms, including sexual, romantic, emotional, or physical. Sexual attraction, behavior, and identity may not always align. Some individuals identify as heterosexual, homosexual, or bisexual without any sexual experience. Others have had homosexual experiences but do not identify as gay, lesbian, or bisexual. Similarly, self-identified gay or lesbian individuals may occasionally have opposite-sex sexual interactions without identifying as bisexual. Terms such as queer, polysexual, heteroflexible, homoflexible, men who have sex with men, and women who have sex with women may also describe sexual identity or behavior. The phrase "bisexual umbrella" or "bisexual community" is sometimes used to refer to any non-monosexual behaviors, attractions, and identities, often for collective action and to challenge monosexist assumptions. This community includes those who identify as bisexual, pansexual, omnisexual, biromantic, polysexual, or sexually fluid.

Bisexuality has also been examined as a transitional identity. One longitudinal study of lesbian, gay, and bisexual youths found evidence of both consistency and change in sexual identity over time. Youths who had previously identified as both gay/lesbian and bisexual were about three times more likely to later identify as gay/lesbian than as bisexual. Among those who had only identified as bisexual earlier, 60 to 70 percent continued to do so, while 30 to 40 percent later assumed a gay or lesbian identity. The researchers suggested that for some youths, a bisexual identity served as a transitional step toward a gay or lesbian identity, though others consistently identified as bisexual throughout the study. In contrast, a ten-year longitudinal study of women identifying as lesbian, bisexual, or unlabeled found that more women adopted bisexual or unlabeled identities than gave them up, and that these women had stable overall distributions of same-sex and other-sex attractions. Another study on male bisexuality noted that almost as many men transitioned from a gay identity to a bisexual, queer, or unlabeled one as did from a bisexual identity to a gay one. There may also be differences over time between sexual and romantic attractions in bisexuals. One study found that in the short term, bisexual men and women were much more likely to change their sexual behavior than heterosexual or homosexual individuals. Bisexual men were less likely to change their romantic attraction, but those who did were more likely to experience a greater change in sexual feelings. Bisexual women were more likely than bisexual men to have a change in romantic attraction, suggesting that sexual and romantic attraction is not fixed for bisexual individuals.