Abstract
The concept of the alpha female has become widely accepted as a form of female identity in the West. Though relationships between hormone concentrations and alpha-related traits have been demonstrated in alpha nonhuman primates, this has not been examined in the case of the human alpha female. The present study examined the associations of testosterone and cortisol, as well as 3 other hormones, estradiol, oxytocin, and progesterone derived from hair samples, with 11 variables related to the expression of the alpha female identity in a small non-random sample (N=126) of self-identified alpha and non-alpha women in North America. The results revealed statistically significant differences between these groups. When compared to non-alpha women, alpha women scored higher than non-alphas in measures for masculinity, leadership, low introversion, self-esteem, and exhibited lower hair cortisol levels. Alphas exhibited slightly lower estradiol and oxytocin levels than non-alphas though these differences were non-significant. Similar non-significant differences were also found in the case of sexual experience, sexual dominance, testosterone, and progesterone. Though cortisol was not associated with masculine traits, it was positively and significantly associated with leadership. Cortisol was also negatively and significantly associated with strength and a measure for femininity. Progesterone, testosterone, and oxytocin were positively and significantly associated with enjoying sex, as was oxytocin with playing a dominant role in sexual encounters. Surprisingly, testosterone was not associated with alpha status nor with the measure of masculinity, and estradiol was not associated with any of the variables. The results imply that women who identify as alpha may experience less physiological stress than non-alpha females as measured by their lower cortisol levels.
Introduction
The influence of hormones includes “intrinsic feedbacks of social context and social behavior on hormones” [1–16]. Behavior is driven by internal and external/environmental stimuli which act on neural systems [16]. The reciprocal relationship between hormones and social behavior demonstrates that hormones do not determine behavior but may increase or decrease the probability of the expression of a given behavior [16]. Given that dominance as a behavioral strategy can be used to gain or maintain high status in society, it is not surprising that a large body of literature has focused on understanding how biological factors, specifically hormones, may influence dominance behaviors [8].
The cross-disciplinary interest in the relationship between social status and hormones is not new [14, 17–26]. Previous research has demonstrated that hormones, specifically cortisol, progesterone, estradiol (primary in women of reproductive age), testosterone, and the peptide hormone oxytocin, correlate with behavioral traits deemed as “alpha” in women [8, 26–35]. For example, attributes including self-assertion, confidence, conceit, forcefulness, control, and willfulness have been associated with higher circulating testosterone levels in women, and lower levels with absence of these alpha traits [28].
Along with engaging in aggressive behaviors, alpha female individuals have also been found to behave in a more cooperative and communal manner [36]. For example, alpha female bonobos maintain cohesion through affiliation while also engaging in aggressive behaviors to keep males away from food [37]. Animal studies have revealed that increased levels of oxytocin are associated with behaviors that promote affiliation, cooperation and prosociality (performing acts that benefit or help others) with other females [38,39]. Communal behavior or affiliation has also been shown to be associated with the expression of the alpha female identity [40]. Research in humans, however, has yet to be conducted. The peptide hormone oxytocin has a special relevance to female behavior because its effects are strongly modulated by estrogen [41]. Estradiol has been linked to dominance behavior. In one-on-one dominance contests, women who expressed higher power motivation also had higher circulating estradiol levels both before and after the contest, compared to women who had lower power motivation [32].
When it comes to hormones and alpha status, much of the research within this context has focused primarily on a specific masculine trait, aggression. For example, Gladue (1991) [42] found that both testosterone and estradiol, were positively correlated with aggression in men. In women however, these correlations were negative [42]. Cashdan [23], examined hormones and competitive aggression in 30 women and found that women with low levels of testosterone were less likely to express their competitive feelings through verbal aggression than women with higher levels of testosterone. That study, however, also found that estradiol was not related to competitive tactics. Women with high estradiol levels reported fewer competitive interactions in athletics than did other women. Aggression has been associated with high testosterone and low cortisol levels in women [26], as well as negatively associated with estradiol levels [32].
While some research has found social rank to be associated with stress in primates as measured by elevated cortisol levels [25, 43, 44], other research has found no association [25]. There is evidence to support that high levels of estradiol and high levels of progesterone are associated with low levels of aggression and that estradiol may also influence behaviors in women other than aggression including dominance, assertiveness, and risk-taking behaviors [26].
More recently, there has been a focus on understanding how hormone levels may jointly influence dominance and other status-seeking behaviors in humans with respect to leadership. Mehta and Josephs [30], examined hormone regulation of dominance in women leaders. They contend that leadership is one of the most important domains within which to study status and social dominance. For their study men and women were randomly assigned to the position of a leader or follower and then asked to complete a leadership task in a simulated competition (how to move blocks to make a specific design). These interactions were video-taped, observations recorded, and each identified leader was rated in terms of dominance. Mehta and Josephs [30] developed a 12-item scale that indexed dominance in leaders. These items assessed dominance as characterized by behaviors linked to, motivation to gain high status including assertiveness, confidence, being energetic, enthusiastic, extraverted, and verbally fluent, display leader-like and directive behavior, being decisive, displaying masculinity and an expansive posture. Using salivary samples, their results revealed that testosterone interacted with cortisol to predict dominance in leaders – that is, dominance in leaders can be predicted by the joint regulation of testosterone and cortisol, where low cortisol and higher testosterone together, are related to increased dominance [30]. In their study on leadership position and circulating testosterone and cortisol levels in male executives, Sherman et al. [14] evaluated the relationship between salivary cortisol and testosterone levels and a measure of attained status – the number of subordinates over which the executive had authority. They found that executive males who exhibited high testosterone and low cortisol levels were more likely to occupy high-status positions whereas low-testosterone, low-cortisol executives were more likely to occupy lower status positions [14]. Testosterone has also been implicated in sexual behavior of women [29]. For example, Udry [45] found that though testosterone was positively related to interest in sexual behavior for both males and females, for females specifically, this interest is only expressed in the absence of a father and low participation in team sports [45].
When it comes to estradiol, progesterone, and the peptide hormone oxytocin however, research is scant. Where research in this area has been undertaken, oxytocin has been found to potentially increase aggression in women by lowering perceptions of danger that would normally inhibit women from retaliating. Low levels of aggression have also been associated with elevated levels of estradiol and progesterone [26]. Though testosterone is required for the expression of masculine traits such as aggression in most vertebrates, including mice and humans, estrogen also plays a role [46]. The enzyme aromatase converts testosterone into estrogen and thus increased levels of testosterone lead to increased levels of estrogen [46]. Despite the dual requirement of estrogen and testosterone for the expression of masculine behaviors, how these dual hormonal pathways are expressed by alpha females has not been examined.
Although it has been established that hormones respond to social context and vice versa [35], what is not clear is how these responses are shaped by social norms related to gender, in this case, a specific archetype of female identity, the alpha female. What is absent from the literature is whether variability in the expression of female identity, specifically between alpha and non-alpha women, may, or may not be connected to neuroendocrine expression. The present research tests the relationships between hormonal and behavioral traits of the alpha female to gain greater insight into our understanding of the alpha female identity from a biosocial perspective. The results of the present study provide an opportunity to better understand whether hormones may represent a biological expression of the alpha female identity. Specifically, the present research seeks to understand the associations between cortisol, testosterone, and alpha female attributes as well as how other hormones such as estradiol, progesterone, and oxytocin, may also play a role in the expression of this female identity. Examined alongside results from recent research on the expression of the alpha female identity which found masculine traits to be a predictor of alpha status [40], it is predicted that alpha women will exhibit higher testosterone but lower cortisol levels than non-alpha females. It is also predicted that testosterone will be positively associated with masculine traits.
Methods
Participants, recruitment and exclusion
Recently, Sumra [40] conducted an extensive review and textual analyses of the academic and popular literature of the human alpha female to examine the social construction and expression of the alpha female identity in a small non-random sample of North American women (N=398). In that study [40], participants completed a 96-question survey and were asked questions in the end of this survey about the alpha female identity. Participants could not go back to change their answers. Included at the end of that survey was a definition of the alpha female following which women were asked to respond yes, no, or maybe as to whether they considered themselves an alpha female based on that definition. That review revealed 2 predominant alpha female representations in the academic and popular literature – one more masculine versus one more feminine – and 21 variables likely to be associated with the expression of the alpha female identity. That study [40] found that the alpha female was a recognized socially constructed female identity. Univariate analysis revealed positive and highly significant differences in self-reported mean scores between alpha (N=94) and non-alpha (N=304) females for 10 variables related to expression of the alpha female identity. In that study [40], the measure of masculine traits was identified as the only predictor of alpha female status as per the multiple regression model. Interestingly, both alpha and non-alpha women scored the same for the measure of feminine traits. Further, both groups scored higher for feminine traits than masculine traits. Participants for the present study were recruited from Sumra’s [40] previous study. As chemical birth control or hormonal therapy may influence hormone levels, women who indicated either were excluded. A total of 32 alpha and 94 non-alpha women remained for a total of 126 participants. The present study evaluates the potential associations between 5 specific hormones (cortisol, estradiol, progesterone, oxytocin, and testosterone), and 10 alpha female -related traits which include measures of masculinity, leadership, strength, low introversion, self-esteem, life satisfaction, sexual experience, initiating sex, enjoying sexual intercourse, and playing a dominant role in sexual encounters, which were found to be associated with the expression of the alpha female identity in Sumra’s 2019 [40] study. The average age category for the sample across all women was 35-37 years, and the average education level was a bachelor’s degree. For those women who were employed the average income was approximately $58,000.00 annually.
Measures
Bem Sex Role Inventory (BSRI) – Masculine and Feminine Personality Traits
Since its development over four decades ago, the Bem Sex Role Inventory or BSRI [47] has been the most commonly used and repeatedly validated measure of gender roles and traits [48]. The original BSRI [47] includes 60 dichotomous items divided into 3 subscales - masculinity, femininity, and neutral. Each subscale includes 20 adjectives that represent typical masculine, feminine, and 20 neutral traits in Western society. The condensed versions of the BSRI-M and BSRI-F based on a total of 10 alpha female related behavioral traits in Sumra’s 2019 work [40] were used in the present study. These versions exhibited adequate internal consistency for both the BSRI-M (Cronbach’s α=0.64) and the BSRI-F (Cronbach’s α=0.72). Respondents were asked to score each item on a 5-point Likert Scale from never (1) to always (5). Means for masculine and feminine categories were calculated to derive corresponding masculinity and femininity scores. Higher masculinity scores indicate higher affiliation with masculine traits, higher feminine scores indicate higher affiliation with feminine traits, equal scores in both masculine and feminine traits indicate androgyny, and low scores in both masculinity and femininity indicate an undifferentiated gender.
The Alpha Female Inventory (AFI) Leadership, Strength and Low Introversion (extroversion)
The subscales of the Alpha Female Inventory (AFI) developed by Ward, Popson, and DiPaolo [49], was used to measure leadership (AFI-L), strength (AFI-S), and extroversion (AFI-LI). The AFI [49] is a 14-item measure of alpha female personality. Items are scored on a 5-point Likert scale from strongly disagree-1 to strongly agree-5 and summed, with higher scores indicating greater levels of leadership (the desire to be a leader, dominant, and assertive), strength (perceived superiority and physical strength), and low introversion (as an index of extroversion). Defined by Ward, Popson, and DiPaolo [49] as “being quiet and withdrawn from social situations”, low introversion, is considered a proxy measure of extroversion. AFI-LI items are reverse-coded where higher scores indicate lower levels of being quiet and withdrawn.
Rosenberg Self-Esteem Scale (RSES) – Self-Esteem
The Rosenberg Self-Esteem Scale (RSES) [50] is a validated measure of self-esteem. Composed of 10 items that assess both positive and negative feelings about the self or “self-worth”, it is the most widely used self-report instrument of confidence and self-esteem [51]. The RSES is unidimensional and items are scored on a 4-point Likert-type scale ranging from strongly disagree (0) to strongly agree (3) [51]. The RSES was modified to reflect an additional choice of neutral (3) to avoid neutral response bias. Research suggests that because negatively worded items may be interpreted differently by different groups, using the RSES may have limited value [52]. Inclusion of a neutral avoids responses at the extreme ends of the RSES [52]. The resulting scale was a 5-point Likert scale ranging from strongly disagree (1) to strongly agree (5). Some questions were also reworded for simplicity and clarity. Items were summed, and higher scores indicated greater self-esteem.
Sexual dominance aspects – Frequency, Dominant Role, Sexual Experience, Initiating, and Enjoying Sex
Five aspects of sexual dominance previously used in Sumra’s 2019 study [40] were assessed. These included sex frequencies, playing a dominant role in sexual encounters, taking initiative in sexual encounters, enjoyment during sex, and sexual experience.
Life Satisfaction
The present study also included an assessment of life satisfaction. A single question was asked, “Describe the level of satisfaction and fulfillment you feel in your life”. Responses were scored on a 5-point Likert scale (0-none, 1-low, 2-moderate, 3-high, and 4-extremely high).
Hair Hormone Analysis
Hair has become recognized as a reliable substrate for measuring hormone concentrations in animals and humans [53–58]. When compared to other methods of sampling such as blood, urine, and saliva, hair sampling is considered most non-invasive, and samples can be collected by non-health care professionals [55]. Unlike urine, saliva, and blood, hormone concentrations in hair are expressed over a longer period of time rather than at a given point in time [59]. In the field of hair hormone analysis, most research in this area has focused primarily on the assessment of chronic stress and the analysis of the stress hormone cortisol in hair [60]. Saliva, blood, and urine are subject to circadian variation in hormone secretion resulting in fluctuating levels over a 24-hour period [61]. For example, salivary, blood, and urinary cortisol levels are typically measured over a 24-hour period usually starting with a first morning sample with subsequent samples taken at intervals throughout the day. Single urine samples collected at any given time reflect cortisol secretion since the last urinary void. Only urine collected throughout the day captures cortisol secretion over a 24-hour period [59]. Where urine samples can provide hormonal profiles for a 24-hour period, saliva and serum provide “point estimates” for cortisol secreted prior to collection (~20 minutes for saliva and <3 minutes for blood) [62].
For the present study, hair samples were sent to a commercial lab (Viagaurd Accu-Metrics, Toronto, Canada) for measurement of cortisol, estradiol, testosterone, progesterone, and oxytocin concentrations. Use of a special collection kit ensured the root ends faced the same direction. Hair were cut close to the scalp to ensure that the sample was collected between periods of dying hair, if hair was dyed on a regular basis. All kits were sealed and stored in individual envelopes. Samples were prepared using the first 3 centimeters of hair closest to the scalp which were washed in isopropyl alcohol by soaking for 5 minutes followed by a rinse. Any hair follicles that were present were cut to ensure that only hormones from the hair shaft were extracted. Because the hair roots had been removed, only hormone concentrations from the hair shaft were extracted. Hair shaft samples were cut into small pieces with surgical scissors then weighed in a 1.5mL tube. The weight of the samples ranged between 0.69 and 3.67 mg. The samples were then ground to a fine powder prior to an overnight extraction in methanol. The supernatant from each of the extractions was then removed and evaporated until completely dry. Once the methanol had been removed, each sample was re-suspended in 250μL of phosphate-buffered saline (PBS) at pH 8.0. The samples were vortexed for 1 min until the extract was dissolved. The cortisol, estradiol, testosterone, progesterone, and oxytocin extracted from the hair were measured using gas chromatography/mass spectrometry with standards for each of these hormones as reference. The dissolved supernatant for each hormone was compared with the standard and normalized with the weight of the hair to give pg/mg values. The respective analytical errors were assessed by replicate measures of cortisol, estradiol, testosterone, progesterone, and oxytocin standards and determined to be ±7 pg/mg.
Ethics Statement
This research, including the method of obtaining informed consent, was approved by the University of Toronto’s Research Ethics Board (Protocol #27117). Informed consent was obtained for each phase of the present study from all participants. Signed consent forms were obtained from those participants who provided hair samples before data collection which were retained by the primary author. Terms of service were adhered to for all social media websites where data were collected.
Statistical Analyses
Descriptive statistics including the mean, median and standard deviation were run for all variables. These included 5 hormone variables CORT (cortisol), EST (estradiol), PROG (progesterone), OXY (oxytocin,) and TEST (testosterone), and the 10 alpha female behavioral variables and the measure of feminine traits identified in Sumra’s [40] 2019 study. Differences between the alpha and non-alpha groups were assessed using nonparametric Mann-Whitney U-tests. All statistical tests were conducted using the Number Cruncher Statistical Systems (NCSS) statistical software package [63].
Results
The results from the Mann-Whitney U tests revealed that when compared to non-alpha females, alpha females (N=32) had significantly higher mean scores for masculine traits (BSRI-M), leadership, low introversion, and self-esteem (RSES), and exhibited lower cortisol (CORT) levels than non-alpha females (N=94) (Table 1). Small but non-significant differences in strength, BSRI-F, life satisfaction, initiates sex and enjoys sex were also found. Alpha females exhibited slightly lower levels of estradiol (EST) and oxytocin (OXY) than non-alphas, and although they scored higher in sexual experience, playing a dominant role in sexual encounters (Dom_Role_Sex), testosterone (TEST), and progesterone (PROG) than non-alpha women, these differences were not significant statistically.
The results from the nonparametric correlation analysis revealed a number of significant relationships (Table 2). Cortisol was positively correlated with leadership and negatively correlated with strength and feminine traits (BSRI-F). Progesterone and oxytocin were positively correlated with sexual enjoyment (Enjoys Sex) as was testosterone. Oxytocin was also positively correlated with playing a dominant role in sexual encounters (Dom_Role_Sex), and negatively correlated with masculine traits (BSRI-M). Estradiol (EST) was not correlated with any of the variables. Leadership position in the workplace as measured by management level is included in (Table 3). Approximately 44% of alpha females held a mid to upper management position versus 35% of non-alpha females.
Discussion
The present study examined the relationship between 5 hormones (cortisol, estradiol, progesterone, oxytocin, and testosterone) and 11 alpha female variables in a small non-random sample of women in North America (N=126). As predicted, alpha women exhibited higher testosterone and lower cortisol levels than non-alpha women. Only the difference in cortisol levels between alpha and non-alphas, however, was statistically significant. Within this context, these results are consistent with similar research in humans [13,14], and non-human primates [20] and contribute to the growing research on dual-hormone patterns with respect to testosterone and cortisol [15, 64]. For example, Sapolsky [20], found that in stable dominance hierarchies of wild olive baboons, subordinate males exhibited higher cortisol levels than alpha males. In Sherman et al.’s [14] study, high testosterone and low cortisol predicted the number of subordinates among male business executives. Other research on the association between cortisol levels and alpha status, however, have revealed mixed results [18, 65].
Alpha individuals are found both to have higher [18, 65] and lower cortisol levels than non-alphas [13, 14, 18, 21]. According to Sapolsky and Ray [65], when it comes to nonhuman primates, dominance style problematizes the validity of low cortisol levels as a marker for alpha status. For example, Sapolsky and Ray [65] found that low cortisol levels are not necessarily a feature of all dominant male baboons in stable hierarchies. Low cortisol levels are exhibited by alpha males who engage in a particular style of dominance in alpha males who display a high degree of social skillfulness, control, and predictability over social hazards, such as, the ability to distinguish between winning or losing a fight [65]. In contrast, alpha males without this skillset were found to have cortisol concentrations as high as subordinate males [65]. Further Sapolsky and Ray [65] found that male baboons who held longer alpha tenure had exhibited lower cortisol levels [65]. This suggests that cortisol levels in alpha individuals may fluctuate over time. In the case of the present research, perhaps the longer a woman identifies as an alpha female, the lower her cortisol levels may be. The results of the present study revealed a positive association between cortisol levels and leadership scores across all women. This result is significant for future research that examines the relationship between cortisol levels in women and leadership position in the workplace.
The finding that testosterone is not correlated with masculine traits in the present group of women is inconsistent with previous research that have found masculine traits to be positively correlated with testosterone concentration in women. For example, Baucom, Besch, and Callahan’s [27] study of 84 undergraduate students who completed Baucom’s Masculinity and Femininity Scales [66] as well as the BSRI and an Adjective Check List, found that women with higher masculinity scores exhibited higher testosterone levels than women with higher femininity scores. They also found that women with higher testosterone levels perceived themselves as self-directed, action-oriented, and resourceful [27]. It is important to note however, that Baucom, Besch, and Callahan [27] stated that masculine-sex-typed females (women who scored higher for masculine traits than feminine traits) exhibited “somewhat” higher testosterone levels than more feminine-sex-typed females (women who scored higher for feminine traits than masculine traits).
Limitations and Future Research
The results of the present research are subject to several important limitations. First, the present study relies on self-identification and does not include data on how those women would be identified by others (e.g. as alpha or non-alpha). Though self-identification and alpha-identity perception (positive, neutral, or negative) could be considered measurable aspects of identity, they are not the only ones. Entativity, or the degree to which groups are perceived by outsiders or non-group members represents another dimension [67]. The opinions and perceptions of non-alpha women and men, and particular self-identified alpha women, may also provide insight into the social construction of the alpha female identity.
The present study is also limited by non-random sampling, and therefore may include some bias, the nature of which is unknown. It is also potentially limited by small sample sizes for both the non-alpha and alpha sampling groups. It is therefore possible that the results do not accurately reflect the differences between these groups of women in North America. Both of these sampling limitations might affect the generalizability of the results to a larger population beyond the scope of the present study.
Similar to Sherman et al. [13], the present findings raise the possibility that higher testosterone levels in conjunction with lower cortisol levels may predispose women to regard themselves as alpha female. Though hormones can affect many aspects of human behavior, the correlations between specific hormones and specific behaviors are often weak and are likely influenced by many factors [68]. As data were collected through the survey and focus groups, self-identified alpha females were not observed in their natural environments limiting insight into how behaviors may be mediated or enhanced by hormones within different social contexts. This is important because humans have complex social lives operating in varying contexts, belong to different social groups and hierarchies, and perform a variety of social roles [22]. Within this context, a self-identified alpha female may not necessarily mean that she is all alpha, all of the time [40]. Future ethnographic research focused on the daily lived experiences and the various contexts of the alpha female may provide greater insight into the potential fluidity and variation in the hormonal expression of the alpha female identity.
Future research that evaluates the relationships between testosterone and cortisol, and female leaders who are considered alpha and non-alpha, may shed light on whether these particular hormones do in fact play a role in the likelihood of occupying a leadership position for women more generally, and more importantly, may also provide the opportunity to gain deeper insight into a potential variant of leadership itself – the alpha female leader. Additionally, the result that leadership is positively associated with stress warrants follow-up research on alpha females who occupy leadership roles.
It is important to note that there have been very few examples in the literature of oxytocin being measured in hair. In one study by Hamel [69], it was determined that hair likely does not provide a good means for measuring long-term oxytocin levels, and that oxytocin may not be incorporated into hair in the same way as cortisol. It is unclear in that study, however, whether the extraction of oxytocin from hair, or measurement by enzyme immunoassay (EIA) is the basis of that determination in that study. As such, it is unclear whether the measurement of oxytocin by mass spectrometry in the present study mitigates the problems with measuring oxytocin in hair suggested by Hamel [69].
Conclusions
The present research contributes to and has direct implications for research on dominance and status-seeking behaviors in humans, specifically research on the human alpha female. It also has direct implications for future leadership and alpha leadership research, and for the study of social hierarchy in organizational research, including research that examines associations between hormones and the attainment of social and professional status [13,14]. The finding that alpha women exhibit lower cortisol levels than non-alpha women also has implications for research on the relationship between alpha status and stress in humans.
Consideration of the findings of the present study alongside with those of Sumra [40], which found that masculine traits predicted alpha status, raises more food for thought on what it means to be an alpha female from a biosocial perspective. Alpha females associate leadership, self-esteem, and being less introverted more with their identity more than other women and they are less stressed as indexed by the hormone cortisol. Thus, the answer to the question “are hormone levels associated with being an alpha female”, for this group of women, is yes, however, only in the case of cortisol.
Supporting Information
S1 File. Rosenberg Self Esteem Scale.
S2 File. BSRI-M and BSRI-F.
S3 File. Alpha Female Sexuality Profile.
S4 File. Alpha Female Inventory (AFI).
Acknowledgments
I would like to thank Dr. Michael Schillaci in the Department of Anthropology at the University of Toronto Scarborough for his support, advice, and critical input.