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. 2020 Nov 13;15(11):e0242262. doi: 10.1371/journal.pone.0242262

Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics: A replication study

Victor Shiramizu 1,*, Ciaran Docherty 1, Lisa M DeBruine 1, Benedict C Jones 1
Editor: Tapio Mappes2
PMCID: PMC7665808  PMID: 33186368

Abstract

Many researchers have proposed that straight men prefer women’s faces displaying feminine shape characteristics at least partly because mating with such women will produce healthier offspring. Although a prediction of this adaptation-for-mate-choice hypothesis is that straight men will show stronger preferences for feminized versus masculinized versions of women’s faces than will gay men, only one previous study has directly tested this prediction. Here we directly replicated that study by comparing 623 gay and 3163 straight men’s preferences for feminized versus masculinized versions of faces. Consistent with the adaptation-for-mate-choice hypothesis of straight men’s femininity preferences, we found that straight men showed significantly stronger preferences for feminized female faces than did gay men. Consistent with previous research suggesting that gay men place a premium on masculinity in potential romantic partners, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men. Together, these findings indicate the sexual orientation contributes to individual differences in men’s face preferences.

Introduction

Many studies of straight men’s face preferences have reported that straight men show strong preferences for female faces with pronounced feminine shape characteristics [1, 2]. These preferences for feminine female faces are widely assumed to at least partly reflect adaptations for mate choice [1, 3]. Specifically, straight men are thought to show strong preferences for feminized versions of women’s faces because mating with such women would produce healthier or more viable offspring [1, 3]. However, evidence that women displaying more feminine facial characteristics possess traits that would cause them to produce healthier, more viable offspring is mixed. For example, while some studies have reported that women with more feminine faces report better general health, such as less frequent colds and other illnesses [e.g. 4, 5], other studies have not found significant correlations between facial femininity and measures of women’s health [e.g. 6, 7]. Although these mixed results suggest the proposed link between women’s actual health and facial femininity, women with more feminine facial characteristics are perceived to be healthier and as likely to be better parents [2].

If straight men show strong preferences for feminized versions of women’s faces because mating with such women would produce healthier or more viable offspring, one might reasonably predict that gay men’s preferences for feminized versions of women’s faces would be weaker than those of straight men. Such results would complement those showing opposite-sex biases in straight participants’ face preferences, which have been widely interpreted as evidence that face preferences at least partly reflect adaptations for mate choice [1, 3]. However, and perhaps surprisingly, only one study has directly tested this hypothesis. In a study of 311 gay men and 215 straight men, Glassenberg et al. [8] found that straight men did indeed show stronger preferences for feminized versus masculinized versions of women’s faces than did gay men. Interestingly, Glassenberg et al. [8] also found that gay men showed stronger preferences for masculinized versions of men’s faces than did straight men, consistent with the proposal that gay men place a premium on masculinity in romantic partners.

Many previously reported findings for individual differences in preferences for sexually dimorphic face shapes have not replicated well in recent large-scale studies [see, e.g., 9]. Consequently, we attempted a direct replication of Glassenberg et al. [8]. We compared 623 gay and 3163 straight men’s preferences for feminized versus masculinized versions of female and male faces. While Glassenberg et al. tested both men and women, our replication study focused on men’s face preferences. Following Glassenberg et al., we predicted that straight men would show stronger preferences for femininity in women’s faces than gay men did and that gay men would show stronger preferences for masculinity in men’s faces than straight men did.

Methods

Participants

Participants for the online study, which was run at faceresearch.org, were 623 men (mean age = 26.4 years, SD = 7.41 years) who reported that their preferred sex of partner was male and 3163 straight men (mean age = 26.65 years, SD = 7.52 years) who reported that their preferred sex of partner was female. No other exclusion or inclusion criteria were applied. 60% of participants reported their ethnicity as White, 20% opted not to report their ethnicity, 6% reported their ethnicity as West Asian, 5% reported their ethnicity as East Asian, and 2% reported their ethnicity as African. All other ethnicities accounted for <1% of our sample. All participants provided informed consent and all procedures were approved by the Psychology Ethics Committee (University of Glasgow).

Stimuli

Following previous studies of individual differences in women’s preferences for masculine faces [e.g., 9, we used prototype-based image transformations to objectively manipulate sexual dimorphism of 2D shape in face images. First, male and female prototype (i.e. average) faces were manufactured using established computer graphic methods that have been widely used in studies of face perception [10]. These prototypes were manufactured using face images of 20 young White male adults and 20 young White female adults, respectively. Next, 50% of the linear differences in 2D shape between symmetrized versions of the male and female prototypes were added to or subtracted from face images of 20 young White male adults and 20 young White female adults. This process created masculinized and feminized versions of the individual face images that differ in sexual dimorphism of 2D shape and that are matched in other regards. Stimuli are publicly available [11].

Procedure

Participants were shown the 40 pairs of face images and were asked to choose the face in each pair that was more attractive. As in Glassenberg et al. [8], the specific instruction was “Which face do you consider more attractive?”. Participants also indicated the strength of these preferences by choosing from the options ‘slightly more attractive’, ‘somewhat more attractive, ‘more attractive’, and ‘much more attractive’. The order in which pairs of faces were shown was fully randomized and the side of the screen on which any particular image was shown was also fully randomized. Responses were coded using a 0 (masculinized face judged as much more attractive than feminized face) to 7 (feminized face judged as much more attractive than masculinized face). These preference scores were centered on chance before being used in our analyses.

Results

Analyses were conducted using R v3.6.0 [12]. Data, analysis code, and full results output are publicly available at https://osf.io/cuqdz/. First, we analyzed preference scores using a mixed effect model using lmer and lmerTest [13, 14] with the factors sexual orientation (effect coded so that gay = -0.5 and straight = 0.5) and sex of face (effect coded so that female = -0.5 and male = 0.5), and the covariate participant age (centered and scaled on mean of sample). We included participant age as a covariate to control for possible effects of age on face preferences [15]. Random intercepts were included for participant and stimulus, with random slopes specified maximally [16, 17]. We did not include the interaction between sexual orientation and participant age in our model.

Results of this initial analysis are summarized in Fig 1. The intercept was significant and positive (estimate = 0.29, SE = 0.06, df = 39.8, t = 4.54, p<0.001), indicating that participants generally preferred feminized versions of faces. The main effect of sexual orientation was significant and positive (estimate = 0.39, SE = 0.03, df = 88.8, t = 11.72, p<0.001), indicating that straight men generally showed stronger preferences for feminized versions of faces than did gay men (see Fig 1). The main effect of sex of face was significant and negative (estimate = -0.90, SE = 0.12, df = 39.2, t = -7.07, p<0.001), indicating that men generally showed stronger preferences for feminized versions of faces when judging the attractiveness of female than male faces (see Fig 1). The effect of participant age was not significant (estimate = 0.01, SE = 0.01, df = 226.6, t = 1.14, p = 0.252). The interaction between sex of face and sexual orientation was significant (estimate = 0.23, SE = 0.06, df = 68.1, t = 3.70 p<0.001) and is illustrated in Fig 1. Repeating this analysis without participant age as a covariate showed the same pattern of results (see robustness analysis reported at https://osf.io/cuqdz/).

Fig 1. The interaction between sexual orientation and sex of face on femininity preference in our study.

Fig 1

Open in a new tab

The box plots and distributions represent the average femininity score for each individual face. The box plots are showing the median, first and third quartile, and the minimum and maximum femininity score for gay (purple) and straight (yellow) participants. On the y-axis, zero equals chance.

Next, we repeated the analysis described above separately for male and female faces and with sex of face removed from the model. Our analysis of female faces showed a significant effect of sexual orientation (estimate = 0.28, SE = 0.03, df = 53.9, t = 7.26, p<0.001), indicating that straight men showed stronger preferences for feminized versions of women’s faces than did gay men (see Fig 1). The effect of participant age was not significant (estimate = -0.01, SE = 0.01, df = 115.4, t = -0.58, p = 0.560). Our analysis of male faces showed a significant effect of sexual orientation (estimate = 0.51, SE = 0.05, df = 37.0, t = 9.89, p<0.001), indicating that gay men showed stronger preferences for masculinized versions of men’s faces than did straight men (see Fig 1). The effect of participant age was significant (estimate = 0.03, SE = 0.01, df = 107.0, t = 2.36, p = 0.019) and indicated that older men showed stronger preferences for feminized male faces.

Preferences for femininity in women’s faces were significantly greater than chance when gay and straight men judged the attractiveness of women’s faces (both ps < .001). Preferences for femininity in men’s faces were significantly lower than chance when gay men judged the attractiveness of men’s faces (p = .002), but did not differ significantly from chance when straight men judged the attractiveness of men’s faces (p = .28).

Discussion

Our analyses showed that straight men demonstrated stronger preferences for feminized versions of women’s faces than did gay men. This pattern of results replicates those reported by Glassenberg et al. [8]. This pattern of results is also consistent with the proposal that straight men’s strong preferences for women’s faces with pronounced feminine characteristics at least partly reflect mating-related motivations [1, 3]. Since women’s faces displaying feminine characteristics are generally ascribed prosocial traits [2], that both gay and straight men showed preferences for feminine version of women’s faces that were significantly greater than chance suggests that men’s preferences for feminine female faces might also partly reflect general preferences for prosocial associates.

Our analyses also showed that gay men demonstrated stronger preferences for masculine men that did straight men. This pattern of results also replicates those reported by Glassenberg et al. [8]. This pattern of results is also consistent with other previous research suggesting that gay men show stronger preferences for men described in vignettes as possessing masculine traits [18]. It is currently unclear why gay men place this premium on masculinity.

A potential limitation of our study was the use of a forced-choice paradigm for assessing men’s preferences for sexually dimorphic face shapes. We used this paradigm in our study because it was the same as that used in the study by Glassenberg et al. [8] that we were attempting to (and successfully did) replicate. However, some recent research suggests that forced-choice paradigms can produce qualitatively different patterns of results than other methods for assessing preferences for sexually dimorphism face-shape characteristics [19]. Establishing the extent to which the effects of sexual orientation on face preferences that we observed in the current study and that were also observed by Glassenberg et al. [8] generalize to other methods for assessing face preferences would be an important direction for future research. Since we only tested male participants, it is also not known whether Glassenberg et al’s findings for women’s face preferences would replicate.

In conclusion, we found that straight men showed stronger preferences for feminized versions of women’s faces than did gay men, consistent with an adaptation-for-mate-choice explanation of straight men’s preferences for feminine women. We also found that gay men showed stronger preferences for masculine men that did straight men. Together these results suggest that sexual orientation influences men’s face preferences.

Data Availability

The data used in this study are available at https://osf.io/cuqdz.

Funding Statement

This work was funded by a European Research Council (ERC) grant (KINSHIP - 647910) awarded to LMD. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

References

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Decision Letter 0

Tapio Mappes

18 Sep 2020

PONE-D-20-06065

Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics

PLOS ONE

Dear Dr. Victor Shiramizu ,

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Reviewer #1: Paper to be reviewed: Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics

1. Is the tittle informative?

I would suggest to include in the tittle the fact that the study is a replication, that way the reader will now straight away what to expect.

2. Does the Abstract clearly identify the need and relevance for this research?

The abstract does identify the need and relevance of the research presented. However, two important findings are mentioned (1: Consistent with the adaptation-for-mate-choice hypothesis of straight men’s femininity preferences, we found that straight men showed significantly stronger preferences for feminized female faces than did gay men; 2: Consistent with previous research, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men), but an explanation is suggested only for the for the first one. I would suggest the authors very briefly state why do they think gay men showed significantly stronger preferences for masculinized versions of male faces.

3. Does the Introduction identify the need and relevance for this research?

Major issues:

The Glassenberg’s study is mentioned, including its main findings, but similarly to the issue with the abstract, there is no reference on how did the authors explained gay men’s preferences for masculinized faces than straight men (e.g., “Our data suggest that face preferences of homosexual individuals reflect a system of bio- logically and socially guided preferences at least as complex as those found among heterosexual individuals”).

The Glassenberg’s study analysed preferences for similarities and differences between straight and gay males and females in reference to their preferences for a facial dimorphism (which isn’t done in the current study). If this study is a partial replication, it should be more specific about what is not being replicated from Glassenbergs. I believe the reader should be given more context about Glassenberg’s paper, and to what extent is this a replication. What is it missing and whats new?

Similarly, the readers may benefit from having more context information about the causes of men’s preferences for women’s feminine faces. What type of health has been measured in women? How has this been done and why is there no consensus?

Minor issues:

There is a typo in the second paragraph, a “THE” should be deleted.

4. Does the Methodology target the main question(s) appropriately?

Minor issues/Major issues:

I believe the methods used to test their hypothesis were appropriate. I appreciated how concise and clear was the description of their methodology, however it would be very helpful to get more details about what were participants asked in reference to the pictures shown. What kind of preference were they specifically asked about? Friends, partner? If the question was only about preferences in general, without any specification, then it should be acknowledged and perhaps the limitations of this addressed.

5. Are the Results clearly and logically presented, and are they justified by the data presented? Are the figures clear and fully described?

The results are clearly presented and are justified by the data presented. However, I was surprised to see that age was at some point included in the model. I wasn’t expecting it as there was no mention about any relationship between age and facial preferences in the introduction. I would suggest including a paragraph where all the predictions are stated and a potential explanation and references are given to the reader.

In terms of the figures, these were clear and fully described in their labels. I appreciated the inclusion if minimum and maximum femininity scores for both conditions (gay vs. straight).

6. Does the discussion justifiably respond to main questions the author(s) posed? Do the Conclusions go too far or not far enough based on the results?

I believe that the authors need to specify that this is a partial replication, as their sample only included men. In line with this, the conclusion that this study is a replication of Glassenger’s study may be going too far. The addition of more context of the extent of the replication will suffice.

In the first paragraph of the discussion, the authors say that pattern of results found “at least partly reflects mating-related motivations”, it would be very helpful to compliment this sentence with what other possible motivations it could reflect.

I would also suggest that the authors include an explanation for gay men preferring more masculine faces than straight men. As of right now, they are only stating the facts, but have not suggested why they think this is the case in their study.

7. Is the manuscript’s story cohesive and tightly reasoned throughout? If not, where does it deviate from the central argument?

The manuscript does present a cohesive story, however I believe that it would greatly benefit from the above comments, specially including a more detailed description of how it is, and how it isn’t a replication of Glassenger’s study.

I look forward to reviewing this manuscript’s next round of edits and seeing it published soon.

Reviewer #2: This study examined differences in facial preferences for faces of both genders in straight vs gay men. The methods and design are very straightforward. Straight men preferred feminine women’s faces more than gay men did. In contrast, gay men preferred masculine men’s faces more than straight men did. However, even with the straightforward results, I find that the MS is far too brief. Here is a list of issues that need to be addressed:

1. The introduction is very thin on the theoretical motivation of the paper. I am not really sure why a difference between straight and gay men is considered a “critical hypothesis”. Does the theory really predict that straight men need to show a stronger preference than gay men? To my mind, a null results wouldn’t have diminished the evolutionary account, nor does a significant difference provide strong support for the evolutionary account. I would like to suggest the authors provide more details on the theoretical motivation.

2. What is the ethnicity of the raters? Do results change after controlling for ethnicity (if ethnicity if mixed)?

3. Even though the results show a difference between straight and gay men, we do not know if there is a preference within each group of men. This information is critical for the interpretation of the results because we need to know that straight men do indeed show a preference for feminine women’s faces.

4. The discussion is equally brief. I would like to see more in-depth discussion of the results. For example, how does the effect size compare to that of the previous study?

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Reviewer #1: Yes: Martha Lucia Borras Guevara

Reviewer #2: No

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PLoS One. 2020 Nov 13;15(11):e0242262. doi: 10.1371/journal.pone.0242262.r002

Author response to Decision Letter 0

9 Oct 2020

Reviewer #1: Paper to be reviewed: Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics

1. Is the tittle informative? I would suggest to include in the tittle the fact that the study is a replication, that way the reader will now straight away what to expect.

We have clarified this point in the title (New title: Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics: A replication study)

2. Does the Abstract clearly identify the need and relevance for this research? The abstract does identify the need and relevance of the research presented. However, two important findings are mentioned (1: Consistent with the adaptation-for-mate-choice hypothesis of straight men’s femininity preferences, we found that straight men showed significantly stronger preferences for feminized female faces than did gay men; 2: Consistent with previous research, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men), but an explanation is suggested only for the for the first one. I would suggest the authors very briefly state why do they think gay men showed significantly stronger preferences for masculinized versions of male faces.

We have clarified in the abstract that the results for male faces are consistent with the proposal that Consistent with previous research suggesting that gay men place a premium on masculinity in potential romantic partners, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men.

Text added to Abstract: “Consistent with previous research suggesting that gay men place a premium on masculinity in potential romantic partners, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men. “

3. Does the Introduction identify the need and relevance for this research? Major issues: The Glassenberg’s study is mentioned, including its main findings, but similarly to the issue with the abstract, there is no reference on how did the authors explained gay men’s preferences for masculinized faces than straight men (e.g., “Our data suggest that face preferences of homosexual individuals reflect a system of bio- logically and socially guided preferences at least as complex as those found among heterosexual individuals”).

We have clarified this point in our Introduction and abstract.

Text added to Abstract: “Consistent with previous research suggesting that gay men place a premium on masculinity in potential romantic partners, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men.”

Text added to Introduction: “Interestingly, Glassenberg et al. [8] also found that gay men showed stronger preferences for masculinized versions of men’s faces than did straight men, consistent with the proposal that gay men place a premium on masculinity in romantic partners.”

The Glassenberg’s study analysed preferences for similarities and differences between straight and gay males and females in reference to their preferences for a facial dimorphism (which isn’t done in the current study). If this study is a partial replication, it should be more specific about what is not being replicated from Glassenbergs. I believe the reader should be given more context about Glassenberg’s paper, and to what extent is this a replication. What is it missing and whats new?

We have clarified in our Introduction that we have replicated the part of the Glassenberg et al. study related to male, not female, participants.

Text added to Introduction: “While Glassenberg et al. tested both men and women, our replication study focused on men’s face preferences.”

Similarly, the readers may benefit from having more context information about the causes of men’s preferences for women’s feminine faces. What type of health has been measured in women? How has this been done and why is there no consensus?

We have clarified this issue in our Introduction.

Text added to Introduction: “For example, while some studies have reported that women with more feminine faces report better general health, such as less frequent colds and other illnesses [e.g. 4, 5], other studies have not found significant correlations between facial femininity and measures of women’s health [e.g. 6, 7]. Although these mixed results suggest the proposed link between women’s actual health and facial femininity, women with more feminine facial characteristics are perceived to be healthier and as likely to be better parents [2].”

Minor issues: There is a typo in the second paragraph, a “THE” should be deleted.

We have fixed this typo.

4. Does the Methodology target the main question(s) appropriately? Minor issues/Major issues: I believe the methods used to test their hypothesis were appropriate. I appreciated how concise and clear was the description of their methodology, however it would be very helpful to get more details about what were participants asked in reference to the pictures shown. What kind of preference were they specifically asked about? Friends, partner? If the question was only about preferences in general, without any specification, then it should be acknowledged and perhaps the limitations of this addressed.

We have clarified that participants were instructed to click on the face that was more attractive.

Text added to Methods: “Participants were shown the 40 pairs of face images and were asked to choose the face in each pair that was more attractive. As in Glassenberg et al. [8], the specific instruction was “Which face do you consider more attractive?”. Participants also indicated the strength of these preferences by choosing from the options ‘slightly more attractive’, ‘somewhat more attractive, ‘more attractive’, and ‘much more attractive’.”

We disagree that is would be appropriate to consider this question a limitation because asking participants to choose the more attractive face for specific contexts would necessarily confound instruction context, sex of face, and participant sexual orientation.

5. Are the Results clearly and logically presented, and are they justified by the data presented? Are the figures clear and fully described? The results are clearly presented and are justified by the data presented. However, I was surprised to see that age was at some point included in the model. I wasn’t expecting it as there was no mention about any relationship between age and facial preferences in the introduction. I would suggest including a paragraph where all the predictions are stated and a potential explanation and references are given to the reader.

We now note that age was included as a covariant because it has been found to relate to men’s face preferences in some previous work [15] and added a robustness analysis showing that the interaction between sex of face and sexual orientation is significant when age is not included in the model.

We have also clarified our predictions in our Introduction (“Following Glassenberg et al., we predicted that straight men would show stronger preferences for femininity in women’s faces than gay men did and that gay men would show stronger preferences for masculinity in men’s faces than straight men did.”)

In terms of the figures, these were clear and fully described in their labels. I appreciated the inclusion if minimum and maximum femininity scores for both conditions (gay vs. straight).

6. Does the discussion justifiably respond to main questions the author(s) posed? Do the Conclusions go too far or not far enough based on the results? I believe that the authors need to specify that this is a partial replication, as their sample only included men. In line with this, the conclusion that this study is a replication of Glassenger’s study may be going too far. The addition of more context of the extent of the replication will suffice.

We have clarified this point in the Discussion and Introduction.

Text added to Introduction: “While Glassenberg et al. tested both men and women, our replication study focused on men’s face preferences.”

Text added to Discussion: “Since we only tested male participants, it is also not known whether Glassenberg et al’s findings for women’s face preferences would replicate.”

In the first paragraph of the discussion, the authors say that pattern of results found “at least partly reflects mating-related motivations”, it would be very helpful to compliment this sentence with what other possible motivations it could reflect.

We have commented on this in our Discussion.

Text added to discussion: “Since women’s faces displaying feminine characteristics are generally ascribed prosocial traits [2], that both gay and straight men showed preferences for feminine version of women’s faces that were significantly greater than chance suggests that men’s preferences for feminine female faces might also partly reflect general preferences for prosocial associates.”

I would also suggest that the authors include an explanation for gay men preferring more masculine faces than straight men. As of right now, they are only stating the facts, but have not suggested why they think this is the case in their study.

We have clarified that it is not clear why gay men place a premium on masculinity.

Text added to Discussion: “Our analyses also showed that gay men demonstrated stronger preferences for masculine men that did straight men. This pattern of results also replicates those reported by Glassenberg et al. [8]. This pattern of results is also consistent with other previous research suggesting that gay men show stronger preferences for men described in vignettes as possessing masculine traits [17]. It is currently unclear why gay men place this premium on masculinity.”

7. Is the manuscript’s story cohesive and tightly reasoned throughout? If not, where does it deviate from the central argument? The manuscript does present a cohesive story, however I believe that it would greatly benefit from the above comments, specially including a more detailed description of how it is, and how it isn’t a replication of Glassenger’s study. I look forward to reviewing this manuscript’s next round of edits and seeing it published soon.

Reviewer #2: This study examined differences in facial preferences for faces of both genders in straight vs gay men. The methods and design are very straightforward. Straight men preferred feminine women’s faces more than gay men did. In contrast, gay men preferred masculine men’s faces more than straight men did. However, even with the straightforward results, I find that the MS is far too brief. Here is a list of issues that need to be addressed: 1. The introduction is very thin on the theoretical motivation of the paper. I am not really sure why a difference between straight and gay men is considered a “critical hypothesis”. Does the theory really predict that straight men need to show a stronger preference than gay men? To my mind, a null results wouldn’t have diminished the evolutionary account, nor does a significant difference provide strong support for the evolutionary account. I would like to suggest the authors provide more details on the theoretical motivation.

We have clarified in our Introduction that this pattern of results would complement previous research on straight individuals that have interpreted opposite sex biases in face preferences as evidence for adaptation to mate choice.

Text added to Introduction: “If straight men show strong preferences for feminized versions of women’s faces because mating with such women would produce healthier or more viable offspring, one might reasonably predict that gay men’s preferences for feminized versions of women’s faces would be weaker than those of straight men. Such results would complement those showing opposite-sex biases in straight participants’ face preferences, which have been widely interpreted as evidence that face preferences at least partly reflect adaptations for mate choice [1,3].”

2. What is the ethnicity of the raters? Do results change after controlling for ethnicity (if ethnicity if mixed)?


We now report in our Methods that the majority of our participants are white.

Text added to Methods: 60% of participants reported their ethnicity as White, 20% opted not to report their ethnicity, 6% reported their ethnicity as West Asian, 5% reported their ethnicity as East Asian, and 2% reported their ethnicity as African. All other ethnicities accounted for <1% of our sample.

3. Even though the results show a difference between straight and gay men, we do not know if there is a preference within each group of men. This information is critical for the interpretation of the results because we need to know that straight men do indeed show a preference for feminine women’s faces.


We have clarified that these preferences were significantly different from chance in our Results: “Preferences for femininity in women’s faces were significantly greater than chance when gay and straight men judged the attractiveness of women’s faces (both ps < .001). Preferences for femininity in men’s faces were significantly lower than chance when gay men judged the attractiveness of men’s faces (p = .002), but did not differ significantly from chance when straight men judged the attractiveness of men’s faces (p = .28).”

Text added to Results: “Repeating this analysis without participant age as a covariate showed the same pattern of results (see robustness analysis reported at https://osf.io/cuqdz/).”

4. The discussion is equally brief. I would like to see more in-depth discussion of the results. For example, how does the effect size compare to that of the previous study?

Comparing effect sizes between the two studies is not straightforward since Glassenberg et al. aggregated preferences across trials, whereas our LME model takes into account variation across trials.

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Decision Letter 1

Tapio Mappes

30 Oct 2020

Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics: a replication study.

PONE-D-20-06065R1

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Acceptance letter

Tapio Mappes

5 Nov 2020

PONE-D-20-06065R1

Sexual orientation predicts men’s preferences for sexually dimorphic face-shape characteristics: A replication study

Dear Dr. Shiramizu:

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