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RESEARCH ARTICLE

Misperception of the facial appearance that

the opposite-sex desires

David I. Perrett*, Iris J. HolzleitnerID¤a

, Xue Lei¤b

School of Psychology & Neuroscience, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom

¤a Current address: School of Social Sciences, University of the West of England, Bristol, United Kingdom

¤b Current address: School of Business Administration, Zhejiang University of Finance and Economics,

Hangzhou, China

* dp@st-andrews.ac.uk

Abstract

Thin and muscular have been characterised as body shape ideals for women and men,

respectively, yet each sex misperceives what the other sex desires; women exaggerate the

thinness that men like and men exaggerate the muscularity that women like. Body shape

ideals align with stereotypic perceptions of femininity in women and masculinity in men. The

present study investigates whether misperception of opposite-sex desires extends to femi- ninity/masculinity in facial morphology. We used interactive 3D head models to represent

faces varying in sexual dimorphism. White European heterosexual men and women were

asked to choose their own and ideal face shape, the ideal shape of a short- and a long-term

partner, and the face shape they thought the opposite sex would most like for a short- and a

long-term partner. Women overestimated the facial femininity that men prefer in a partner

and men overestimated the facial masculinity that women prefer in a partner. The discrep- ancy between own and ideal sexual dimorphism (an index of appearance dissatisfaction)

covaried with by the misperception of what the opposite-sex desires. These results indicate

misperception of opposite-sex facial preferences and that mistaken perceptions may con- tribute to dissatisfaction with own appearance.

Introduction

Research on body image reveals a misperception of the body shape desired by others which

may contribute to dissatisfaction with own appearance. This study assesses whether there is a

similar misperception in the sexual dimorphism of facial shape desired by others and whether

the degree of overestimation predicts dissatisfaction with own facial appearance. The study

hypotheses were not pre-registered.

Thin and muscular body ideals

In Western countries, the ideal female figure is thin (e.g., [1]) while the ideal male figure is

lean and muscular (e.g., [2]). The drive to attain an ideal body shape leads to unhealthy behav- iour including excessive dieting to lose weight in women [3] and use of anabolic steroids to

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OPEN ACCESS

Citation: Perrett DI, Holzleitner IJ, Lei X (2024)

Misperception of the facial appearance that the

opposite-sex desires. PLoS ONE 19(11):

e0310835. https://doi.org/10.1371/journal.

pone.0310835

Editor: Johannes Ho ̈nekopp, Northumbria

University, UNITED KINGDOM OF GREAT BRITAIN

AND NORTHERN IRELAND

Received: June 10, 2024

Accepted: September 2, 2024

Published: November 14, 2024

Peer Review History: PLOS recognizes the

benefits of transparency in the peer review

process; therefore, we enable the publication of

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responses alongside final, published articles. The

editorial history of this article is available here:

https://doi.org/10.1371/journal.pone.0310835

access article distributed under the terms of the

Creative Commons Attribution License, which

permits unrestricted use, distribution, and

reproduction in any medium, provided the original

author and source are credited.

Data Availability Statement: The data that support

the findings of this study are openly available on

the Open Science Framework at https://osf.io/

3rkxz/?view_only=

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develop muscles in men [4,5]. While there are pressures from the media, peers and family that

contribute to individuals’ dissatisfaction with their appearance [6–8], a further contributing

factor to body dissatisfaction may be the misperception of opposite-sex preferences.

Women overestimate the thinness that men desire in a partner [9–12] and men overesti- mate the heaviness and muscularity that women desire in a partner [9,11–14]. The nature and

extent of these misperceptions are important as they may contribute to the adoption of

unhealthy attitudes and behaviour. For example, in women, the extent of misperception of

male desires predicts the extent of unhealthy eating attitudes and disordered eating behaviour

[10].

Body shape desires reflect stereotypic concepts of femininity and

masculinity

Thinness in women and muscularity in men are attributes that are stereotypically linked to

concepts of femininity and masculinity. Guy et al. [15] found that, for USA college students, a

thin woman’s body shape was sex-typed feminine whereas a lean muscular male body was sex- typed masculine. Indeed, from a very early age, body thinness is associated with femininity.

Pre-school girls aged 3–5 years are emotionally invested in the thin is positive stereotype and

associate female thinness with feminine traits [16]. Indeed, for both girls and boys, stereotypic

feminine traits (e.g., likes children) were more strongly associated with a thinner female figure

than with a fatter one [17]. Conversely, muscular physiques are viewed by men as being mas- culine (e.g., [18]). For example, McCreary et al. [19] concluded that men believe “those with a

greater degree of muscularity are more masculine and that gaining muscularity increases one’s

masculinity.”

The misperception of opposite-sex desires extends to other features of sexual dimorphism.

Women overestimate the bust-to-waist ratio that men find attractive [20]. Perhaps conse- quently most women would prefer to have bigger breasts [21]. Since misperception is wide- spread and frequently relates to feminine and masculine attributes, there is reason to

anticipate that there will be a misperception of the sexual dimorphism in face shape that the

opposite-sex desires.

Sexual dimorphism in face shape

Masculinity in male face shape has variable effects on attractiveness [22] with some studies

reporting that women prefer masculinised male faces while other studies find no effect or a

preference for feminised male faces.

In industrial populations, male facial masculinity relates strongly to a dominant appearance

[23] which is an important attribute for intra-sexual competition amongst men. One indica- tion that male masculinity might be a sign of good quality, at least in industrialised societies

[24], comes from consideration of competition in the ‘mating market’ [25]. Good quality from

this limited perspective refers to individuals that are desired as a partner, and who can out- compete rivals in their own quest to secure a desirable partner. Multiple attributes contribute

to mate quality (including resources, youth and physical attractiveness). Several studies have

reported that women who consider themselves as more attractive than average prefer a higher

degree of male facial masculinity than women that consider themselves less attractive [26–31]

although Alharbi et al. [32] reported a null finding in an Arab sample). Hence, facial masculin- ity in men can be considered as a sign of quality in the mating market.

Such individual differences in masculinity preferences can arise if both facial masculinity in

men and attractiveness in women are considered signs of good quality. Competition for part- ners predicts that a high-quality individual will be able to form a stable partnership with

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46a7dd9adae048218c328ab9a912b331 The data

are also available at https://figshare.com/articles/

dataset/Misperception_of_the_desirability_of_

sexual_dimorphism/26424307?file=48071893.

Funding: The author(s) received no specific

funding for this work.

Competing interests: The authors have declared

that no competing interests exist.

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another individual of similar high quality. Reciprocally individuals of lower quality will tend to

form partnerships with similar quality individuals. Hence, competition results in assortative

mating for quality where like pairs with like. Such an argument considers only one dimension

of quality; real pairings will be multifactorial and will involve trade-offs between attributes.

Furthermore, what constitutes a mark of quality varies between populations [33].

There is less dispute that sexually dimorphic characteristics in women such as femininity of

body shape [34] and face shape [35] and even hair length [36] increase attractiveness.

As argued above, an indication that feminine characteristics in women are a sign of quality

(at least in Western societies, [33,37]) comes from consideration of competition. In a similar

manner to that described above, men who rate themselves as attractive prefer a higher degree

of female facial femininity than men who consider themselves as less attractive [27,31,38,39].

Hence, from the perspective of competition, sexual dimorphism in face shape can be consid- ered a desirable quality for both men and women in industrial societies.

Independent of how facial dimorphism might signal quality, it is evident that dimorphism

influences attractiveness in both men and women. Hence, people may be concerned about the

degree to which their facial masculinity or femininity conforms to ideals. Individuals may

aspire to higher levels of dimorphism than they themselves exhibit, since this would make

them more competitive in acquiring a high-quality mate. As noted for sexually dimorphic

aspects of body shape, the opposite sex is often predicted to desire a more exaggerated appear- ance than they prefer. In the same way, the dimorphism in facial appearance that is predicted

to be desired by the opposite sex may be exaggerated. Women may have an exaggerated notion

of the facial femininity that men desire, and men may have an exaggerated notion of the facial

masculinity that women desire.

Dissatisfaction with appearance

In research on body image, participants are often presented with a range of body shapes along

a continuum from underweight (emaciated) to overweight (obese) and asked to choose a

shape which best fits their current body shape, and their ideal body shape. A measure of per- ceived dissatisfaction with own physiognomy is derived from difference between perception of

ideal body shape and own body shape [40–42]. This discrepancy (own minus ideal) is associ- ated with a person’s wellbeing and self-esteem: Kostanski and Gullone [43] reported that par- ticipants with a high level of dissatisfaction with their perceived body image had low self- esteem and high levels of anxiety and depression.

One can derive a similar index of dissatisfaction for facial dimorphism. This index can be

computed as the difference between the participant’s ideal facial dimorphism and the partici- pant’s own facial dimorphism (ideal minus own dimorphism). This index will be used here as

a proxy for dissatisfaction with facial appearance. In an analogous way to body image dissatis- faction, we predict that many participants will exhibit dissatisfaction with own facial appear- ance being lower in sexual dimorphism than the participant’s ideal.

Misperception of the desires of others may be a contributing factor to dissatisfaction with

own appearance. Lei and Perrett [12] found that the extent of body image dissatisfaction in

both men and women was predicted by the misperception of what the opposite sex desired in

body shape. Here we investigate whether misperception of facial dimorphism desired by the

opposite sex predicts dissatisfaction with facial dimorphism.

Most men choose an ideal body shape that is heavier and more muscular than how they

perceive their own body to be. Reciprocally, women choose an ideal that is skinnier than what

they perceive their own body to be (e.g., [12]). If women have a high body mass, then they are

likely to have a greater discrepancy with their ideal body mass index. Hence, in investigating

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dissatisfaction in facial morphology it is important to control for the participant’s own facial

morphology.

Relationship context

A factor affecting mate choice preferences is relationship context. Long-term relationships

come with direct benefits (to the participant) of parental investment, resources and safety,

whereas short-term relationships can have indirect genetic benefits (to the participant’s off- spring) but only temporary resources [44]. Different partner characteristics are therefore

desired more in different contexts [45].

Preference for sexual dimorphism seems to be stronger in contexts where investment in a

relationship is deemed less important, making relationship type a crucial distinction when

investigating mate preferences. For both men and women, facial attractiveness has been

shown to depend on the relationship context considered, with greater levels of sexual dimor- phism preferred for short-term relationships compared to long-term relationships [39,46,47].

Moreover, greater exaggeration in body-shape ideals has been found in judgements made for

short-term relative to long-term relationship contexts [12]. Therefore, it is anticipated that

exaggeration of sexual dimorphism in face shape desired by another will be greatest in short- term relationship contexts.

Hypotheses

The general prediction is that men and women will overestimate the level of sexual dimor- phism in facial appearance that is desired by the opposite sex. To test this, we measure the

male face shape that participant women desire and compare this to the face shape that men

predict women will desire. Reciprocally, we measure the female face shape that participant

men desire and compare this to the face shape that women predict men will desire.

The following hypotheses will be tested:

(H1) The level of facial masculinity that men predict women desire will be higher than the

masculinity women actually prefer.

(H2) Men’s misperception will be greater in a short- than a long-term relationship context.

(H3) The level of facial femininity that women predict men desire will be higher than the femi- ninity men actually prefer.

(H4) Women’s misperception will be greater in a short- than a long-term relationship context.

(H5) The facial masculinity men think is ideal will be higher than the masculinity they think

corresponds to their own face shape.

(H6) The facial femininity women think is ideal will be higher than the femininity they think

corresponds to their own face shape.

(H7) The size of misperception of opposite-sex desires will covary with men’s and women’s

dissatisfaction with their own face shape (defined as the difference between ideal and own

facial dimorphism).

Materials and methods

The work was approved by the University Teaching and Research Ethics Committee Ethics

Committee of the University of St Andrews (PS13176). All participants gave informed consent

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prior to commencing the experiment. Participants were given a Participant Information Sheet

and were required to fill in an on-line consent form before proceeding to the experiment

proper.

Nomenclature

To disambiguate participants and stimuli, the participants will be referred to as men and

women, and the stimuli will be referred to as male and female. Sexual dimorphism preferences

will be named predictions when participants predict what the opposite sex prefer, and they will

be named preferences for what participants judge most attractive in the opposite sex. Sexual

dimorphism is referred to as masculinity when referring to male stimuli and femininity when

referring to female stimuli.

Participants

Sample size considerations. Lei and Perrett [12] reported misperception of body shape

(body mass index) preference between men and women with effect sizes ranging between

d = 0.4 and d = 0.9. If we assume that misperception of facial shape preferences has a similar

range in effect size we can estimate an appropriate sample size. With a power of 80%, an alpha

error of 0.05 and an effect size of d = 0.4, G-power suggested a sample size of 76 men and 76

women.

A sample of men and women (sex as recorded on legal/official documents) were recruited

via Prolific. Recruitment started on 17th January 2021 at 15:18 and ended 18:35 of the same

day. Pre-screening criteria were applied, which included age from 18 to 26 years old, hetero- sexual orientation, UK residency and White ethnicity. All participants received £1.50 as a

reward for their participation (Median duration 9.3 minutes), a rate of £9.6 per hour that was

considered good by Prolific.com at the time of experiment. One hundred and fifty-three par- ticipants were recruited including 77 men and 76 women. Exclusions were made based on par- ticipants not completing the task (n = 1), reporting sexual orientation <4 on a 1–7 sexual

orientation questionnaire (n = 4) or choosing a “wish not to answer” option (n = 4). This left a

sample of 72 men (age: M = 21.72, SD = 2.67, range 18–26) and 72 women (age: M = 22.28,

SD = 2.69, range 18–27).

Stimuli. The study used 3D stimuli. The stimuli were two male and two female ‘base’

faces. Each of the male base faces was a composite or average of the shape, colour and texture

of four male faces. Likewise, each of the female base faces was a composite of shape, colour and

texture of four female faces. Composite stimuli were employed because they are more repre- sentative (of the category of faces from which they were constructed) than the original faces

[48]. Additionally, the composite images cannot be recognised as known individuals.

These female and male composites or base faces were then feminised and masculinised in

3D shape based on the difference between an average of 50 male faces and an average of 68

female faces [49]. Fig 1 upper shows the shape transformation of the average male face rather

than a base face. Likewise Fig 1 lower shows the transformation of the average female face.

Transformation was achieved by applying or subtracting the linear difference between the

average male face shape and female face shape to target face (i.e. average faces for illustration

and each individual composite or base face for stimuli. The distance from the average female

face shape to the average male face shape was equivalent to a +100% increase in masculinity.

Thus, each of the 118 faces contributed to the definition of the dimorphism vector along

which base faces were manipulated. Importantly, we compared the sexual dimorphism from a

second independent set of 40 male and 40 female faces [50]. The sexual dimorphism vectors

from the within-set and the independent out-of-set faces were both used to assign a

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morphological masculinity score [49,50] for each of the 118 faces. The two sets of scores corre- lated (N = 118, Pearson’s r = .78) [51]. This shows that the face sexual dimorphism shape vec- tor has external validity.

To provide more information on the shape transformation applied [49], shape dimorphism

score varied within the original sample of 68 female faces SD = 33% and within the original

sample of 50 male faces SD = 36%. The difference in facial shape dimorphism scores between

the original sample of male and female faces had an effect size Cohen’s D = 0.34. The two male

base faces were each feminised and masculinised in shape within a range from −100% to

+200%, and the two female base faces were each masculinised and feminised in shape within a

range from −100% to +300% sexual dimorphism. For both female and male faces, 0% corre- sponds to the original, unmanipulated base face. For male faces, negative values correspond to

a decrease and positive values to an increase in masculinity. For female faces, negative values

correspond to a decrease and positive values to an increase in femininity. A less extreme level

of manipulation was chosen for male faces because exaggeration beyond 200% caused glitches

which detracted from the appearance.

The 3D stimuli were imaged in two poses (a frontal and a half profile view). Two views

were simultaneously presented to provide more 3D information (e.g., about chin shape and

eyebrow structure) and because different views affect attributions differently [52]. Participants

were able to transform the faces in increments of 10%, hence there were 30 increments for

male faces and 40 for female.

Procedure

Participants were asked to complete a demographic questionnaire about age, gender, sexual

orientation. They were then presented with a series of two male and two female face stimuli

with sliders below each stimulus that allowed them to manipulate the level of sexual dimor- phism in the display. Participants were not told of the underlying nature of the shape

transform.

Instructions were given before each set of two faces, requiring the participants to use their

computer mouse to move the slider and adjust the face to best match the task description.

Fig 1. Transformation of sexually dimorphic face shape. Upper: The average male face transformed by −100% (feminised), 0% (neutral), +100%

(masculinised) and +200% (masculinised) sexual dimorphism. Lower: The average female face transformed by −100% (masculinised), 0% (neutral), +100%

(feminised) and +200% (feminised) sexual dimorphism. To preserve anonymity of participants, these images are averages of the shape, colour and texture of 50

male faces and 68 female faces, respectively, rather than of real individuals.

https://doi.org/10.1371/journal.pone.0310835.g001

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