Strengths and limitations of this study

• Causality cannot be inferred from this cross-sectional analysis.

• The study drew a convenience sample from a two-year college of undergraduates, limiting its generalizability.

• This sample provided uncommon insight into the research question given that it was from a pedestrian population not uniquely constructed from a preassembled collective solicited, identified, or self-identified by their sexual identity, sexual orientation, social/sexual affiliations, social media affiliations, or counseling/therapy patient populations.

• Given the sample was drawn from a racially diverse non-residential college (no dormitories or organized fraternity/sorority housing), no random or purposeful cohabitation arrangements of undergraduates by a third party (e.g. college dormitory, fraternity/sorority) influenced respondent’s cohabitation or procreation experience.

• This study is unprecedented in that it applied a host of 39 sexual behavior and cohabitation variables correlated to the precept of sexual orientation.

Introduction

The com petence of sexual orientation paradigms to demarcate sexual orientation lack consensus [1-7]. Despite the array of sexual orientation models posited—the Rosetta stone of sexual orientation eludes scholarly validation across, as well as within health, medical, judicial, social, and academic disciplines across the globe. Nevertheless, varied and conflicted models and treatises of sexual orientation are posted as rationales for medical diagnoses and treatment protocols, public health at-risk populations, marital and divorce torts, child welfare policy, affirmative action, as well as public health education diktats. Presently there are societies exacting capital punishment for homosexual behavior concomitant with societies proscribing select pronouns in addressing non-heterosexual persons. Presently there are societies diagnosing persons with gender dysphoria as ‘mentally ill’ concomitant with societies underwriting cross-sex hormones and cross-sex surgical remediation for gender dysphoria. Such imposed practices and torts by health, medical, judicial, social, and academic venues exist in the absence of a theoretical as well as a metric consensus of sexual orientation.

The epicenter of contention is whether the sex of one’s preferred erotic partner is generally a product of ‘nature’ (biological determinism), that being an innate preference for an erotic/relationship partner of a given sex, or a product of ‘nurture’, that being a learned preference for an erotic/relationship partner of a given sex resulting from social conditioning or experienced emotional/physical/sexual trauma. Contemporary conciliations frame the ethos of sexual orientation as a product of both nature and nurture. Nevertheless, the contention remains as to whether the biological determinism of nature or the learned behavior of nurture is most responsible for human sexual orientation. At stake in validating a sexual orientation metric is the interpretation of human sexual behavior as deviant, etiologic, or normative within health, medical, judicial, criminal, social welfare, and academic policies as well as the praxis of society.

Historically, a binary sorting of either male or female, matched to their preferred erotic (romantic) partner’s biological gender (hereafter ‘sex’), was sorted into either heterosexual or homosexual orientation. By the close of the 20^th century concepts of a binary sexual orientation were questioned as to their capacity to represent the sum of human sexual behavior and just as importantly human sexual relationships [5,6,8]. Scholars asserted that binary models of sexual orientation were inherently flawed given the precept of but two sexes (male or female), with the norm being heterosexuality (i.e. heteronormativity). With heteronormativity being the norm, or in spite of heteronormativity being the norm, binary models branded any transient heterosexual incongruity (erotic/relationship same-sex partners) as experimental, inconsequential, or pathological [8-11]. This was most applicable to females than males, given that females invariably report a greater incidence of same-sex erotic behavior.

Rose framed heteronormative models as ‘male focused’ and as such centered on male sexual desires/pleasures (e.g. coitus) thereby relegating female sexual desires such as orgasm and cunnilingus subordinate [12]. Rose argued that binary models inherently discount the female libido. Consorting scholars branded heteronormative binary models as ‘male biased’ and thus incompetent to account for the sum of erotic behavior with sex partners—especially for females.

Critics of heteronormative binary models pointed to bisexual females who identify outside of the heteronormative binary model, as fallible instances in the binary model. By example, Copen et al. identified a pool of approximately 9,000 American females aged 18-44, who self-identified as heterosexual (92.3%), homosexual (1.3%), and bisexual (5.5%) [13]. Here, 5.5% of females self-identified outside of the binary model (bisexual) as well as outnumbered homosexual females by more than four to one. Indeed, a subpopulation of heterosexual females who engage both males and females in sexual pleasuring is recognized in the literature [9,14,15]. In turn, critics cite this sub-population of homoerotic females as an inherent fallibility in sexual orientation binary models.

Accounting for bisexual persons, homoerotic-heterosexual persons, as well as heteroerotic-homosexual persons within a binary paradigm of sexual orientation is problematic. In response, the binary model expanded to a linear model of heterosexual-bisexual-homosexual. Linear models offered an identity schema compatible with the sexual orientation of self-identified heterosexuals, bisexuals, and homosexuals [6,9,13].

Nevertheless, linear models drew their critics. The concern was that static ‘markers’ of sexual orientation failed to account for the construed shifting of sexual orientations by females who self-identify as heterosexual, yet engage in homoerotic behaviors [1,16]. The contention is that linear models of sexual orientation could not account for heterosexual females contemporaneously engaging in homoerotic behavior. This begged the question as to whether a homoerotic experience by a self-identified heterosexual female constituted a shift in her sexual orientation or whether her homoerotic experience was solely a matter of libido satiation with little or no preference for the sex of her erotic partner. Thus, homoerotic nuances by self-identified heterosexual females could not fit within the conceptualization of linear models.

Morgan and Thompson approached ‘shifts’ in sexual orientation by suggesting that the maturation of sex identity is different for heterosexually identified females as opposed to non-heterosexually identified females [17]. Parenthetically this notion implies an imposed influence of biological determinism on sexual identity. Morgan and Thompson rightfully cautioned that research in support of this notion was mainly conducted on populations self-identifying with a sexual-minority. Nevertheless, Morgan and Thompson posited two norms of sexual identity development—one for heterosexually identified females and the other for non-heterosexually identified females. In this conceptual scheme, sexual orientation (i.e. preferred sex erotic partners) reflects a track towards either a heterosexual or a non-heterosexual identity. By design, this is a binary model with the difference being the aggregation of non-heterosexuals juxtaposed to heterosexuals. The sexual orientation waypoints of heterosexual, homosexual, and bisexual revert to a binary dichotomy of either heterosexual or non-heterosexual (e.g. bisexual, homosexual, asexual, transsexual, pansexual, and pedophilia), with each sexual orientation (heterosexual or non-heterosexual) maintaining a theoretical threshold of a ‘preferred sex erotic partner’.

Morgan and Thompson’s view substantiates the observation that for some heterosexual females, their homoerotic behavior is experiential or opportunistic and for other heterosexual females, their homoerotic behavior is on track to a commutative (i.e. preferred) non-heterosexual orientation. As such, observations, especially of young adult females, may be poised snapshots of females in transition, tracking towards a non-heterosexual orientation or conversely females with stable heterosexual orientations experiencing an opportunistic non-heterosexual encounter—with the latter not being a preferred erotic/relationship partner. In essence, homoerotic behavior by a self-identified heterosexual female would not represent a shift in her sexual orientation.

Such instances expose the antinomy within stationed linear models to reconcile the difference between categorical shifts in sexual orientation as opposed to opportunistic homoerotic trysts, void of a sexual orientation shift. It may be that for a sub-population of heterosexual females their sexual orientation does not ‘shift’ when engaging in homoerotic behavior. As such, these females are not tracking permanently or provisionally to a non-heterosexual orientation. Here libido satiation and not romantic ideation with their preferred erotic partner, compels their sexual behavior. That is, when this heterosexual female sub-population is presented with an unavailable male partner or a male partner unable to provide sufficient libido satiation, or an opportunistic homosexual tryst--a female erotic partner is engaged while their heterosexual orientation remains intact.

By example, an incarcerated heterosexual female shifting from her preferred male erotic partner(s) to a female partner, only to shift back to her preferred male erotic partner(s) after release, may not mark a provisional shift in her sexual orientation. This suggests that the orientation waypoints in linear models of female sexual orientation are indeed static with homoerotic behavior wholly a product of libido satiation—thus inconsistent with a shift in sexual orientation.

Sociosexuality attempts to account for transient homoerotic behavior in heterosexuals as well as heterosexual behavior in homosexuals. Sociosexuality is described as one’s willingness to engage in uncommitted or libido-dominated sexual behavior. Sociosexuality is vicariously portrayed as an attitude, attitude and behavior, endocrinological dictate, personality trait, as well as a narcissistic personality disorder [18-20]. While there is some evidence that sociosexual attitude-behavior is stronger for females than males, sociosexuality lacks endocrinological evidence supporting the hypothesis that females’ desire for uncommitted sexual relationships is positively related to estradiol and negatively related to progesterone. Jones et al. reported that the effects of estradiol were largely confined to the domain of females’ solitary sexual desire and that their results were consistent with the effects of hormonal status of general sexual desire, but not sociosexual orientation [18].

Without endocrinological evidence (nature) for heterosexual female homoerotic sociosexual behavior, scholars countered with an array of attitudinal, behavioral, and personality triggers for female sociosexual behavior from ‘game playing infidelity’ to the female (libido) compensating for an unattractive yet committed male partner [19,21]. Sociosexuality suggests that there is no shift in sexual orientation by its proviso that female homoerotic behavior can be a matter of libido satiation and not a condition for a provisional or permanent shift to a preferred erotic/relationship sex partner.

Diamond suggested that heterosexual female homoerotic behavior is an expression of the relationship between sexual desire and love and advanced the ‘biobehavioral model’ [22]. The bio behavioral model underscores an emotional relationship threaded or founded in one’s preference for an erotic partner. That being the case, the biobehavioral model would view ‘recreational’ or ‘opportunistic’ homoerotic behavior by self-identified heterosexual females as not representing a provisional or permanent shift in sexual orientation.

To account for, as well as integrate heterosexual females ‘recreational’ or ‘situational’ homoerotic behavior into a sexual orientation model, ‘dynamic sexual orientation’ models were advanced. Dynamic sexual orientation models posit female sexual orientation as experientially multi-directional, being dynamic rather than stationed. ‘Sexual fluidity’ or ‘heteroflexiblity’ models posit that shifts in sexual orientation are examples of the female libido dominating the female’s sexual identity (sexual self-concept) and sexual attraction preference [3,23-28]. By eliminating ‘fixed’ stations in linear models, dynamic sexual orientation models endeavor to explain female vacillation between heterosexual-bisexual-homosexual behaviors as a metric of her ‘present state’ of erotic partners, ergo sexual orientation. Revisionists contend that dynamic models account for the homoerotic sexual behaviors/practices of heterosexual females as well as heterosexual behaviors of homosexual females, by interpreting their associative sexual behavior as characteristic of a dynamic (plastic) sexual orientation. The implication is that sexual identity and sexual attraction ultimately succumb to the will of the libido, resulting in a provisional shift in sexual orientation, and consequently the sex of one’s erotic partner marks a shift in their sexual orientation.

In response to the multitude of sexual orientation interpretations Bailey et al. identified four archetypal elements of sexual orientation that are, sexual behavior, sexual identity (one’s self-conception), degree of sexual attraction, and relative physiological sexual arousal [2]. Notably the metrics of sexual attraction and physiological sexual arousal have no empirical benchmark (i.e. ‘degree’ of sexual attraction, and ‘relative’ physiological sexual arousal.) However, combined with sexual behavior and sexual identity, these four elements constitute the threshold of sexual orientation.

Sexual fluidity and heteroflexiblity by relegating sexual identity and sexual attractiveness as inferior (possibly inconsequential) archetypal elements--essentially alters the metrics and salience of orientation in sexual orientation. Dynamic sexual orientation models by definition lessen the notion of a ‘preferred’ sex erotic partner. Such libido governing models cast sexual orientation as a condition of libido satiation at the moment, irrespective of any element of a preferred sex (male or female) partner as well as irrespective of the presence of a sexual orientation relationship that affirms one’s sexual identity. This notion is problematic.

Regardless of social construct or scripted roles, one’s libido can subvert one’s sexual orientation. Nonetheless, one’s libido is served by one’s sexual orientation. Indeed, males and females will capitulate to their libido in defiance of social norms and historically have done so under penalty of ostracisation, incarceration, and even capital punishment. This can account for sexual orientation transgressions as not shifts in sexual orientation, but instead libido accommodations [3].

Baumeister suggests that female libido accommodations are products of the libido ‘plasticity’ of sexual orientation [28]. Here the ‘preferred’ sex for an erotic partner ‘relationship’ is of trivial or no measure. Diamond suggested that libido accommodations are founded in a ‘relational’ sex vis-à-vis sexual orientation, thus manifest displays of sexual identity [24]. Here the relationship element is present as confirmation of sexual identity vis-à-vis sexual orientation. Such opposed inferences accounting for libido accommodations in female sexual orientation models underscore the impasse in classifying homoerotic behavior of self-identified heterosexual females as shifts in sexual orientation.

If transient homoerotic behavior in heterosexual females is libido driven and not a proviso of sexual orientation—we would expect a difference between homoerotic-heterosexual females and heterosexual females in libido satiation experience. We would not expect a preferential sex partner difference between homoerotic-heterosexual females and heterosexual females in their cohabitation and procreation experience. The purpose of this study was to determine homosexual and heterosexual sex partner preferences of self-identified heterosexual females, in their erotic behavior and cohabitation/procreation sex partners. This investigation will contribute to the theoretical and empirical rationale for female sexual orientation paradigms.

Materials and Methods

A retrospective cross-sectional survey utilizing a convenience sample was drawn from the general population of undergraduates at a public, northeastern, non-residential community college. The college enrollment was 23 938 with a median age of 22.0 years. In all, 1 846 instruments were submitted of which 1 830 instruments were coded. The 1 830 respondents represented 7.6% of the undergraduate enrollment that semester. Of the 1 830 respondents, 1 028 were females. Two transgender respondents were removed from the analysis.

Procedures

Respondents were recruited from intact Health Education course sections that were either required or elective courses for all but five of the college’s degree programs. Respondents were 18 years or older. Consent forms were obtained from each respondent. There were no identifiers linking respondents to their responses. Classroom seating was arranged in formal test-taking configuration. The in-class survey was voluntary, anonymous, and averaged 39 minutes. Respondents opting out of the survey completed an in-class worksheet. Participants placed their instrument or worksheet in an unmarked sealed envelope and then into a cloaked ballot box. This study was sanctioned by the University’s Institutional Research Review Committee.

Measures

The instrument records in part, comprehensive demographics of race, ethnicity, natal gender, and sexual orientation. The instrument records tallies of respondents’ masturbatory, oral-genital, and coital practices including initiation age, partner’s age at initiation, number of lifetime partners, and frequency in the last month and year [29]. Previous studies reported a .85 to .91 reliability coefficient for the instrument [30,31]. The instrument’s reliability coefficient (Cronbach’s Alpha) for ‘ever experienced’ masturbatory, oral-genital, and coital practices under investigation in this study was .91.

Tests of Significance

Tests of significance (SPSS IBM Advanced Statistics Version 24.0.0) were chi-square (X²) for nominal variables, independent-sample t tests (t), and a stepwise discriminate analysis. Type 1 error rate was set to .05. Results with insufficient tallies for testing were generally not reported.

Hypotheses

Of the 1 028 were female respondents, 805 (N = 805) self-identified as ‘lifetime’ heterosexuals (i.e. exclusive of self-reported homosexual or bisexual orientations). They were divided into either Heterosexuals (n = 776) or Homoerotic-Heterosexuals (n = 29). Homoerotic-Heterosexuals had to satisfy at least two of three criteria: (1) had performed cunnilingus in the last year and/or had performed cunnilingus on multiple lifetime partners; (2) had received cunnilingus in the last year and/or had received cunnilingus from multiple lifetime female partners; and (3) had performed or received analingus from a female partner in the last year and/or had performed or received analingus with multiple lifetime female partners.

The following null hypotheses were tested:

H_1: There are no significant differences between Homoerotic-Heterosexuals and Heterosexuals and their sexual rites of passage (age initiation) for:

H_1a: heterosexual oral-genital stimulation.

H_1b: homosexual oral-genital stimulation.

H_1c: coitus.

H_2: There are no significant differences between Homoerotic-Heterosexuals and Heterosexuals and their oral-genital stimulation experience with male partners.

H_3: There are no significant differences between Homoerotic-Heterosexuals and Heterosexuals and their oral-genital stimulation experience with female partners.

H_4: There are no significant differences between Homoerotic-Heterosexuals and Heterosexuals and their experiential coital practices.

H_5: There are no significant differences between Homoerotic-Heterosexuals and Heterosexuals and their cohabitation/procreation practices.

Results

Demographics

There were significant differences in age between Homoerotic-Heterosexuals and Heterosexuals (t (768) = 4.607, p = 0.000). Homoerotic-Heterosexuals (M = 19.77, SD = 2.20) were significantly younger than Heterosexuals (M = 21.94, SD = 5.24). There were no significant differences in race/ethnicity between Homoerotic-Heterosexuals and Heterosexuals with 11.2% White; 23.6% African descent; 42.8% Hispanic (non-White); 0.8% American Indian or Alaskan Native; 12.0% Asian or Pacific Islander; 6.4% multi-racial; and 3.2% other. There were no significant differences between Homoerotic-Heterosexuals and Heterosexuals in their siblings’ gender or number of siblings from the same biological parents or different biological parents. There were no significant differences between Homoerotic-Heterosexuals and Heterosexuals in their birth country with 59.7% born in the United States.

Sexual Rites of Passage

Univariate ANCOVA was calculated with age as the covariant for scaled variables, given the significant age difference between Homoerotic-Heterosexuals and Heterosexuals.

Heterosexual Oral-genital Stimulation

Homoerotic-Heterosexuals were significantly younger than Heterosexuals at their age initiation for receiving male performed cunnilingus. Homoerotic-Heterosexuals were significantly younger than Heterosexuals at their age initiation for first performed fellatio (Table 1).

Homosexual Oral-genital Stimulation

There were no significant differences between Homoerotic-Heterosexuals and Heterosexuals at their age initiation for female partner cunnilingus. Homoerotic-Heterosexuals and Heterosexuals were notably similar in age at their first performed cunnilingus, first received cunnilingus by a female partner, and first performed cunnilingus while simultaneously receiving cunnilingus from a female partner.

Coitus

Homoerotic-Heterosexuals were not significantly younger than Heterosexuals at their age initiation for coitus. However, Homoerotic-Heterosexuals had significantly more coital partners in the last year than Heterosexuals (Table 1).

Sexual Experience

Masturbation

Significantly more Homoerotic-Heterosexuals (79.2%) than Heterosexuals (54.5%) had ever masturbated (Table 2).

Homosexual Oral-genital Practices

Significantly more Homoerotic-Heterosexuals (58.6%) than Heterosexuals (4.6%) ever received female performed cunnilingus. Significantly more Homoerotic-Heterosexuals (55.2%) than Heterosexuals (4.4%) ever performed cunnilingus. Significantly more Homoerotic-Heterosexuals (27.6%) than Heterosexuals (1.0%) ever performed cunnilingus while receiving cunnilingus from a female partner. Significantly more Homoerotic-Heterosexuals (10.3%) than Heterosexuals (0.6%) ever received female performed analingus (Table 2).

Heterosexual Oral-genital Practices

Significantly more Homoerotic-Heterosexuals (89.7%) than Heterosexuals (62.5%) ever received male performed cunnilingus. However, there was no significant difference between Homoerotic-Heterosexuals and Heterosexuals who ever performed fellatio. Significantly more Homoerotic-Heterosexuals (65.5%) than Heterosexuals (40.5%) ever performed fellatio while receiving cunnilingus from a male partner (Table 2).

Coital Practices

Respondents reported whether they ‘ever’ experienced select coital practices. Significantly more Homoerotic-Heterosexuals (96.6%) than Heterosexuals (69.6%) ever had coitus. Significantly more Homoerotic-Heterosexuals (69.0%) than Heterosexuals (42.1%) ever had a coital orgasm. Significantly more Homoerotic-Heterosexuals (51.7%) than Heterosexuals (25.1%) ever faked a coital orgasm. Significantly more Homoerotic-Heterosexuals (58.6%) than Heterosexuals (30.0%) ever consumed alcohol before coitus. There was no significant difference between the groups in their using marijuana before coitus (Table 2).

Significantly more Homoerotic-Heterosexuals (41.4%) than Heterosexuals (24.2%) ever had coitus with a male of a different race/ethnicity. Significantly more Homoerotic-Heterosexuals (34.5%) than Heterosexuals (12.9%) ever had coitus on a first date. Significantly more Homoerotic-Heterosexuals (17.2%) than Heterosexuals (2.1%) ever had polyamorous ‘sex’ with a male and a female partner. Significantly more Homoerotic-Heterosexuals (24.1%) than Heterosexuals (7.2%) ever had coitus while viewing erotica. Significantly more Homoerotic-Heterosexuals (34.5%) than Heterosexuals (13.0%) ever had coitus while photographing or video recording themselves (Table 2).

Prostitution

Respondents reported whether a ‘male ever paid to have sex’ with them. There was a significant difference between Homoerotic-Heterosexuals and Heterosexuals ever having a male pay to have sex with them (X² (1, N = 805) = 10.653, p = 0.031). Significantly more Homoerotic-Heterosexuals (6.9%) than Heterosexuals (0.8%) ever had a male pay to have sex with them.

Procreational Practices

There was no significant difference between Homoerotic-Heterosexuals (23.1%) and Heterosexuals (31.2%) ever being pregnant. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in the outcome (i.e. miscarriage, abortion, birth) of their first pregnancy (Table 3). However, 0.0% of Homoerotic-Heterosexuals as opposed to 33.9% of Heterosexuals opted for a live birth. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their partner relationship (i.e. married, cohabiting, single) for their first pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in informing the biological father of their pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their intention to become pregnant for their first pregnancy (Table 3). However, 0.0% of Homoerotic-Heterosexuals as opposed to 16.9% of Heterosexuals intended their first pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their partners’ intention to father. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their intention to abort their first pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their partners’ intention to abort the pregnancy (Table 3).

Cohabitation Practice

Respondents reported whether they ever cohabited with a female in a sexual relationship for more than six months. There was no significant difference between Homoerotic-Heterosexuals (0.0%) and Heterosexuals (1.7%) in ever cohabiting with a female in a sexual relationship for more than six months. Respondents reported whether they ever cohabited with a male in a sexual relationship for more than six months. There was no significant difference between Homoerotic-Heterosexuals (15.8%) and Heterosexuals (24.3%) in ever cohabiting with a male in a sexual relationship for more than six months.

Stepwise Discriminate Analysis

A stepwise discriminate analysis generated four predictor variables, which comprised the discriminate stepwise function equation (D-metric): (1) age first performed fellatio; (2) number of lifetime coital partners, (3) age at a first date coitus, and (4) age received first male performed analingus. The discriminate function accounted for 88.7% of variability between Homoerotic-Heterosexuals and Heterosexuals. The cross-validated classification model yielded a robust 84.3% correct classification between Homoerotic-Heterosexuals and Heterosexuals.

Disposition of Null Hypotheses

The H₁ null hypotheses tested for differences between Homoerotic-Heterosexuals and Heterosexuals age initiation for: heterosexual oral-genital stimulation, homosexual oral-genital stimulation, and coitus. Homoerotic-Heterosexuals were significantly younger than Heterosexuals at age initiation for receiving male performed cunnilingus and age initiation for first performed fellatio. The H_1a null hypothesis was rejected. Despite controlling for age, Homoerotic-Heterosexuals exhibited a precocious libido for receiving male performed cunnilingus as well as performing fellatio compared to Heterosexuals.

Homoerotic-Heterosexuals and Heterosexuals were notably similar in age at their first: (1) performed cunnilingus, (2) received cunnilingus by a female partner, and (3) performed cunnilingus while simultaneously receiving cunnilingus from a female partner. In turn, the H1b null hypothesis failed to be rejected. Homoerotic-Heterosexuals and Heterosexuals did not exhibit age initiation dissimilarity for receiving or performing cunnilingus with female partners.

Homoerotic-Heterosexuals were not significantly younger than Heterosexuals at their age initiation for coitus. In turn, the H_1c null hypothesis failed to be rejected. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever received male performed cunnilingus. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever performed fellatio while receiving cunnilingus from a male partner. However, there was no significant difference between Homoerotic-Heterosexuals and Heterosexuals performing fellatio. The H₂ null hypothesis was rejected. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever received male performed cunnilingus while there was no significant difference between either group ever performing fellatio.

Significantly more Homoerotic-Heterosexuals than Heterosexuals ever received cunnilingus or performed cunnilingus with female partners. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever received analingus with female partners. The H3 null hypothesis was rejected. Homoerotic-Heterosexuals were significantly more experienced than Heterosexuals with cunnilingus and analingus with female partners. This observation was expected based on the grouping variable.

Significantly more Homoerotic-Heterosexuals than Heterosexuals ever had coitus and a coital orgasm. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever consumed alcohol just before coitus. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever had coitus with a male of a different race/ethnicity or had had coitus on a first date. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever had male and female polyamorous ‘sex’ partners. Significantly more Homoerotic-Heterosexuals than Heterosexuals ever had coitus while viewing erotica or while photographing/video recording themselves. None of the Homoerotic-Heterosexuals ever cohabited with a female. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in ever cohabiting with a male. The H4 null hypothesis was rejected. Homoerotic-Heterosexuals reported more coital experience with a wider breadth of coital practices than Heterosexuals, yet did not exhibit any sexual cohabitation preference for female partners.

There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals ever being pregnant or their intention to become pregnant for their first pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their partner relationship (i.e. married, cohabiting, and single) for their first pregnancy. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their partners’ intention to father a child. There was no significant difference between Homoerotic-Heterosexuals and Heterosexuals in their intention or their partners’ intention to abort their first pregnancy. The H₅ null hypothesis failed to be rejected. Homoerotic-Heterosexuals and Heterosexuals were remarkably similar in their procreational experience with male partners.

Discussion

This study examined homosexual and heterosexual sex partner preferences of self-identified heterosexual females, in their erotic behavior and cohabitation/procreation sex partners. The data revealed significant differences in precocious and lifetime sexual behavior experience between homoerotic-heterosexual and heterosexual females.

Historical sexual orientation paradigms integrate elements of the ‘preferred’ erotic sex partner with that of a sex identity confirming ‘relationship’. Dynamic sexual orientation paradigms subordinate the conditions of a preferred erotic sex partner as well as a preferred relationship. In this study, homoerotic-heterosexual females were more libido driven in their sex behavior, especially for coitus as well as cunnilingus by both male and female partners. However, homoerotic-heterosexual females did not report any preferential sex partner difference in their lifetime cohabitation and procreation experience when compared to heterosexual females. Historical sexual orientation paradigms would judge the erotic and relationship experience of homoerotic-heterosexual females in this sample as insufficient for a shift in their sexual orientation to homosexual or bisexual. Dynamic sexual orientation paradigms would judge the erotic experience of homoerotic-heterosexual females in this sample as transient (fluid) shifts in their sexual orientation from heterosexual to homosexual, to possibly bisexual.

Sexual orientation models that discount or discard the preferred (sex attraction) relationship element risk misconstruing libido idiosyncrasies or libido preferences such as cunnilingus, as shifts in sexual orientation. By example, the posited inclusion of pedophilia (e.g. nepiophilia and ephebophilia) and chronophilia redefines sexual attractiveness to include the age of a preferred sex partner as a (dynamic) sexual orientation waypoint. Here the sexual orientation model strays beyond male or female, into a libido governed trait or ideation (e.g. innocent, Asian, submissive, blond hair). That pedophilia is a ‘philia’ satisfies the libido. However, this posited waypoint of sexual orientation is no longer based solely on the sex of the erotic partner. In turn, the precept of sexual orientation, which is actually ‘sex’-orientation, is fundamentally altered to a construct of ‘libido orientation’ so as to accommodate ideations such as pedophilia as a sexual orientation waypoint.

By casting ‘libido orientations’ as sexual orientations--stigmatophilia, morphophilia, and hybristophilia present as waypoints on a sexual orientation continuum. Problematic with this concept is that the erotic partners in such sexual orientations may have little to do with their biological sex and all to do with their being non-consenting, forbidden, tattooed, naive, sleeping, small breasted, blonde, or a criminal. Here ‘sex’ (biological male or female) is secondary or perhaps a non sequitur to sexual orientation.

This research exercise exposes two points of contention within contemporary sexual orientation models. The first being whether sexual orientation is mostly a matter of sex orientation or libido orientation. It is reasonable to assert that by any standard sexual orientation is a classification by the sex of one’s preferred erotic partner. For the sake of clarity, the term ought to be modified to ‘sex orientation’. The ‘sexual’ in sexual orientation, that is the physically arousing traits, ideations, scenarios, fantasies, philias, and the like should be codified in a cornucopia of ‘libido orientations’.

Given the precept that ‘sex orientation’ is a matter of one’s sex preferred erotic partner, the second contention focuses on the archetypal elements of (1) ‘degree’ of sexual attraction and (2) ‘relative’ physiological sexual arousal. Dynamic sexual orientation models assert that female homoerotic behavior inherently bear a ‘degree’ of sexual attraction as well as a ‘relative’ physiological arousal threshold, and thus constitutes a shift in sexual orientation. Such a premise miscalculates the libido’s ability to circumvent the threshold of sexual attraction as well as a threshold of physiological sexual arousal, so as to be sexually satiated.

Key to the threshold of sexual attraction is the preference of a male and/or female partner in an erotic relationship that confirms one’s sexual identity. Erotic behavior where the physiological sexual arousal is high but the sexual attraction is low, seems insufficient for a shift in sex orientation. Erotic behavior where the physiological sexual arousal is low but the sexual attraction is high is sufficient for a shift in sex orientation. This premise asserts that the ‘preferred’ male and/or female partner by complimenting (confirming) one’s sexual identity satisfies the threshold of ‘sexual attraction’. A ‘preferred’ sex partner that compliments one’s sexual identity who engenders little physiological sexual arousal (i.e. insufficient threshold) or no longer engenders any physiological sexual arousal--still reflects one’s sex orientation. A female may crave receiving cunnilingus by a male and/or female partner while preserving her heterosexual orientation, which affirms her sexual identity. This was displayed by the homoerotic females in this study. Thus, the presence of a partnered sex behavior is insufficient for a shift in sexual orientation unless that partner is the ‘preferred sex partner affirming one’s sexual identity. This binds any shift in sex orientation to a shift in sexual identity. In this study, both the homoerotic-heterosexual females and heterosexual females self-identified as heterosexual. While the homoerotic-heterosexual females reported a much greater libido satiation experience with male and female erotic partners—they self-identified as heterosexual. There was no fluid, provisional or tracked shift in the sex orientation of these homoerotic-heterosexual females.

The implication of this construct of ‘sexual orientation’ sets the metric for ‘sex orientation’ as the preferred male and/or female erotic partner affirming one’s (self-identified) sexual identity. In this model, the threshold for the ‘degree’ of sexual attractiveness is in the male and/or female preference that affirms one’s sexual identity. In this model, the threshold of ‘relative’ physiological sexual arousal is inherently met by the male and/or female (sex) preference that affirms one’s sexual identity. In turn, the element of sexual behavior has no threshold in ‘sex orientation’. This construct of sex orientation provides health, medical, judicial, social, and academic venues a common metric for determining sex orientation.

Libido orientation is the preference for an erotic persona, ideation, scenario, or an amalgamation of erotic personas, ideations, or scenarios. Libido orientation is void of any sex (male and or female) metric. Thus, the sex orientation of a male sexually craving pre-teen girls is heterosexual. The sex orientation of a male sexually craving pre-teen boys is homosexual. The libido orientation of a male sexually craving pre-teen girls or pre-teen boys, or both is pedophilia. The conceptualization of sexual orientation into sex orientation and libido orientation provides health, medical, judicial, social, and academics a common model for comprehending human sexual behavior as well as consensus rationale for appraising human sexual behavior.

Conclusions

In this study, homoerotic-heterosexual females reported a more precocious sexual awakening with a greater breadth and experience of coital and oral-genital practices than heterosexual females. Yet, homoerotic-heterosexual females mimicked the cohabitation and procreation experience of heterosexual females. The sexual behavior and sex partner preference of homoerotic, self-identified heterosexual females in this study was not indicative of a shift in their sexual orientation to female. In turn, dynamic sexual orientation models are at risk in misclassifying homoerotic-heterosexual female behavior as a shift in sexual orientation. As such, the operate conceptualization of sexual orientation ought to be divided into sex orientation and libido orientation. Whereas sex orientation is a classification of the sex of one’s preferred erotic partner that affirms one’s (self-identified) sexual identity. Libido orientation is the preference for an erotic persona, ideation, scenario, or an amalgamation of erotic personas, ideations, or scenarios, void of any sex classification. The conceptualization of sexual orientation into a dichotomy of sex orientation and libido orientation provides health, medical, judicial, social, and academics worldwide a common model for comprehending human sexual behavior as well as coherent rationale for appraising human sexual behavior.

Compliance with Ethical Standards

Compliance with Ethical Standards: This study was approved by The City University of New York Institutional Research Review Board (IRB NET#: 11-12-037-0140). Informed consent was obtained from all individual participants included in the study. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Financial disclosure: None

Conflict of interest: None

	n	M	SD	F	df1/df2	p-value	η2
Age Received First Male Performed Cunnilingus				5.275	1.494	.022	.01
Heterosexuals	471	17.04	2.32
Homoerotic Heterosexuals	25	15.60	2.90
Age First Performed Fellatio				4.748	1. 424	.030	.01
Heterosexuals	407	17.40	2.45
Homoerotic Heterosexuals	19	15.79	1.78
Number of Coital Partners in the Last Year				17.329	1. 546	0	.03
Heterosexuals	522	1.55	1.64
Homoerotic Heterosexuals	26	3.11	3.80

References

1. Albury K (2015) Identity plus? Bi-curiosity, sexual adventurism and the boundaries of ‘straight’ sexual practices and identities. Sexualities 18: 649-664.
2. Bailey M, Vasey P, Diamond L, Breedlove SM, Vilain E, et al. (2016) Sexual orientation, controversy, and science. Psychol Sci Public Interest 17: 45-101.
3. Carrillo H, Hoffman A (2018) ‘Straight with a pinch of bi’: The construction of heterosexuality as an elastic category among adult US men. Sexualities 21: 90-108.
4. Fahs B (2009) Compulsory bisexuality? The challenges of modern sexual fluidity. J Bisex 9: 431-449.
5. Farr RH, Diamond LM, Boker SM (2014) Female same-sex sexuality from a dynamical systems perspective: sexual desire, motivation, and behavior. Arch Sex Behav 43: 1477-1490.
6. Garnets LD, Peplau LA (2000) Understanding women’s sexualities and sexual orientations: An introduction. J Soc Issues 56: 181-192.
7. Robinson M (2013) Polyamory and monogamy as strategic identities. J Bisex 13: 21-38.
8. Diamond L (2005) “I’m straight, but I kissed a girl”: The trouble with american media representations of female-female sexuality. Fem Psychol 15: 104-110.
9. Johns M, Zimmerman M, Bauermeister J (2013) Sexual attraction, sexual identity, and psychosocial wellbeing in a national sample of young women during emerging adulthood. J Youth Adolesc 42: 82-95.
10. Rich A (1980) Compulsory heterosexuality and lesbian existence. Signs: Journal of Women in Culture and Society 5: 631-660.
11. Silva T, Whaley R (2018) Bud-sex, dude-sex, and heteroflexible men: The relationship between straight identification and social attitudes in a nationally representative sample of men with same-sex attractions or sexual practices. Sociol Perspect 61: 426-443.
12. Rose S (2000) Heterosexism and the study of women’s romantic and friend relationships. J Soc Issues 56: 315-328.
13. Copen CE, Chandra A, Febo-Vazquez I. (2016) Sexual behavior, sexual attraction, and sexual orientation among adults Aged 18-44 in the United States: Data from the 2011-2013 national survey of family growth. Natl Health Stat Report 88: 1-14.
14. Chandra A, Copen C, Mosher W (2013) Sexual behavior, sexual attraction, and sexual identity in the United States: Data from the 2006–2010 national survey of family growth. In: Baumle A. eds. International handbooks of population, international handbook on the demography of sexuality Volume VI. Dordrecht, Switzerland: Springer Science and Business Media Dordrecht. 45-66.
15. Diamond L (2008) Female bisexuality from adolescence to adulthood: Results from a 10-year longitudinal study. Dev Psychol 44: 5-14.
16. Savin-Williams R, Ream G (2007) Prevalence and stability of sexual orientation components during adolescence and young adulthood. Arch Sex Behav 36: 385-394.
17. Morgan E, Thompson E (2011) Processes of sexual orientation questioning among heterosexual women. J Sex Res 48: 16-28.
18. Benedict CJ, Amanda CH, Fisher CI, Hongyi W, Michal K, et al. (2018) General sexual desire, but not desire for uncommitted sexual relationships, tracks changes in women's hormonal status. Psychoneuroendocrinology 88: 153-157.
19. Miller J, Widiger T, Campbell W (2010) Narcissistic personality disorder and the DSM–V. J Abnorm Psychol 119: 640-649.
20. Webster G, Bryan A (2007) Sociosexual attitudes and behaviors: Why two factors are better than one. J Res Pers 41: 917-922.
21. Gangestad S, Thornhill R, Garver-Apgar C (2005) Women’s sexual interests across the ovulatory cycle depend on primary partner developmental instability: Proceedings of the royal society of london B. London, England: Royal Society of London: 2023-2027.
22. Diamond L (2003) What does sexual orientation orient? A biobehavioral model distinguishing romantic love and sexual desire. Psychol Rev 110:173-192. 
23. Baumeister R, Stillman T (2006) Erotic plasticity: Nature, culture, gender, and sexuality. In McAnulty R, Burnette M, eds. Sex and Sexuality, Volume 1. Westport: Praeger Press 343-359.
24. Diamond L. Sexual fluidity: Understanding women’s love and desire. Cambridge, MA: Harvard University Press 2008.
25. Frank K (2008) Not gay, but not homophobic: Male sexuality and homophobia in the lifestyle. Sexualities 11: 435-454.
26. Keppel B (2006) "Affirmative psychotherapy with older bisexual women and men". J Bisex 6: 85-104. McCormack M (2018) Mostly straights and the study of sexualities: An introduction to the special issue. Sexualities 21: 3-15.
27. Thompson E, Morgan E (2008) “Mostly straight” young women: variations in sexual behavior and identity development. Dev Psychol 44: 15-21.
28. Baumeister R (2000) Gender differences in erotic plasticity: The female sex drive as socially flexible and responsive. Psychol Bull 126: 347-374.
29. Belcastro P, Ramsaroop HH (2018) Examining the sexual enigma of the immigrant paradox with international students. Journal of International Students 8: 1783-1814.
30. Belcastro P (1983) A comparison of latent sexual behavior patterns between raped and never raped female victims. Victomology: An International Journal 7: 224-230.
31. Belcastro P (1985) Sexual behavior differences between black and white students. J Sex Re 21: 56-67.