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Beards augment perceptions of men's age, social status, and aggressiveness, but not attractiveness

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The beard is a strikingly sexually dimorphic androgen-dependent secondary sexual trait in humans. Darwin posited that beards evolved in human ancestors via female choice as a highly attractive masculine adornment. Others have since proposed that beards evolved as a signal of male status and dominance. Here, we show that women from two very different ethnic groups, Europeans from New Zealand and Polynesians from Samoa, do not rate bearded male faces as more attractive than clean-shaven faces. Women and men from both cultures judge bearded faces to be older and ascribe them higher social status than the same men when clean-shaven. Images of bearded men displaying an aggressive facial expression were also rated as significantly more aggressive than the same men when clean-shaven. Thus, the beard appears to augment the effectiveness of human aggressive facial displays. These results are consistent with the hypothesis that the human beard evolved primarily via intrasexual selection between males and as part of complex facial communication signaling status and aggressiveness.
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Behavioral Ecology
doi:10.1093/beheco/arr214
Advance Access publication 13 January 2012
Original Article
Beards augment perceptions of men’s age,
social status, and aggressiveness, but not
attractiveness
Barnaby J. Dixson
a
and Paul L. Vasey
b
a
School of Biological Sciences, Victoria University of Wellington, PO Box 600, Kelburn Parade,
Wellington 6140, New Zealand and
b
Department of Psychology, University of Lethbridge, 4401,
University Drive, Lethbridge, Alberta T1K 3M4, Canada
The beard is a strikingly sexually dimorphic androgen-dependent secondary sexual trait in humans. Darwin posited that beards
evolved in human ancestors via female choice as a highly attractive masculine adornment. Others have since proposed that
beards evolved as a signal of male status and dominance. Here, we show that women from two very different ethnic groups,
Europeans from New Zealand and Polynesians from Samoa, do not rate bearded male faces as more attractive than clean-shaven
faces. Women and men from both cultures judge bearded faces to be older and ascribe them higher social status than the same
men when clean-shaven. Images of bearded men displaying an aggressive facial expression were also rated as significantly more
aggressive than the same men when clean-shaven. Thus, the beard appears to augment the effectiveness of human aggressive
facial displays. These results are consistent with the hypothesis that the human beard evolved primarily via intrasexual selection
between males and as part of complex facial communication signaling status and aggressiveness. Key words: aggressiveness,
attractiveness, beard, dominance, facial hair, sexual selection. [Behav Ecol 23:481–490 (2012)]
INTRODUCTION
Overall reduction in body hair distinguishes Homo sapiens
from other anthropoids. Nuclear genetic studies suggest
that hairlessness in Hominids dates back to 1.2 Ma (Rogers
et al. 2004). While human body hair is sparse, strictly speak-
ing, people are not hairless. During prenatal development,
the fetus is covered in primary lanugo hairs, which are re-
placed by secondary vellus hairs during early postnatal life
(Trotter and Duggins 1948;Szabo 1967;Price and Griffiths
1985). Lanugo and vellus hairs are short, fine, unpigmented,
and lack a medulla (Trotter 1938;Garn 1951). During infancy,
childhood, and adolescence, vellus hairs differentiate into ter-
tiary terminal hairs in specific parts of the body (Garn 1951;
Szabo 1967). Compared with vellus hairs, terminal hairs
are coarser, longer, more heavily pigmented, have thicker
roots, and contain a larger medulla (Price and Griffiths
1985;Randall 2008).
Terminal hair on the head, eyelashes, and eyebrows grow un-
der the influence of androgens and growth hormones. Andro-
gens also promote the growth of terminal hair in other regions
of the body so that both men and women grow pubic and ax-
illary hair. However, at puberty, males undergo surges in andro-
gens, which drive sex differences in the growth of more
pronounced terminal hair on the face and body (Randall
2008). Sexual dimorphism in facial hair first appears at
around age 10 in children (Trotter 1922). Beard hair contin-
ues to grow in early adolescence and is fully developed at
sexual maturity (Hamilton 1958). Beard hair is thicker, has
a more complex medulla and a larger root compared with
hair on the scalp and elsewhere on the head (Garn 1951;
Szabo 1967;Tolgyesi et al. 1983;Thozhur et al. 2006).
People of different ethnic groups vary in pattern, distribution,
and density of beard and body hair(Setty 1971;Lookingbill et al.
1991;Winkler and Christiansen 1993). However, although
men’s beards and body hair growth are stimulated by testoster-
one (Ewing and Rouse 1978;Farthing et al. 1982), ethnic
differences in hirsuteism should not be attributed to levels of
total or free testosterone (Rosenfield et al. 1976;Ewing and
Rouse 1978;Lookingbill et al. 1991). Rather, it is the conversion
of testosterone into dihydrotestosterone, through the enzyme 5-
alpha-reductase, which primes coetaneous androgen-sensitive
receptor cells to invest in terminal follicle growth on the face
(Randall 2007,2008). Beard growth is almost identical in mono-
zygotic twins, less similar between nonidentical twins, and shows
the most variation between nontwin brothers (Hamilton 1958;
Hamilton et al. 1958). Thus, genetic factors appear to regulate
the extent to which the growth of facial and body hair occurs
under the influence of androgens (Hamilton 1964).
Using natural selection as a starting point, many hypotheses
have been proposed for the reduction of body hair in humans
(for review, see Rantala 2007). For example, it has been sug-
gested that as ancestral hominids transitioned from arboreal
to savannah conditions, loss of body hair was adaptive for
cooling (Morris 1967;Wheeler 1992a,1992b). Another, more
recent hypothesis proposes that due to the development of
cooperative hunting and fixed home bases, loss of body hair
may have lessened disease-carrying ectoparasites (Rantala
1999,2007). Given that humans have lost thermoregulatory
pelage important in other anthropoid primates, why have
men retained conspicuous hair on the body and face? There
have been attempts to account for the evolution of the beard
Address correspondence to Barnaby J. Dixson. E-mail: barnaby.dixson@
vuw.ac.nz.
Received 17 August 2011; revised 6 November 2011; accepted 27
November 2011.
The Author 2012. Published by Oxford University Press on behalf of
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via natural selection to assist in thermoregulation or protec-
tion against UV radiation (Cabanac and Brinnel 1988,2000;
Green et al. 2006). Consistent with such accounts, research
shows, for example, that beard growth in men in the United
Kingdom was 50–60% greater in summer months than in
winter months (Randall and Ebling 1991). However, the ab-
sence of pronounced facial hair in women makes extrapolat-
ing evolutionary significance from these findings within the
context of natural selection questionable.
Sexual selection, which operates both intra- or intersexually,
provides an alternative evolutionary framework to natural se-
lection for investigating the evolution of facial hair in men.
Intrasexual selection among males favors the evolution of sex-
ually dimorphic characteristics that augment, or signal, com-
petitive ability (Darwin 1871;Andersson 1994;Hunt et al.
2004). In this vein, Blanchard (2010) suggested that the hu-
man beard evolved to protect against blows to the jaw in the
same way as a lion’s mane. However, studies of the attack
patterns of male lions have not supported the hypothesis that
the mane serves such a protective function (West et al. 2006).
Zahavi and Zahavi (1997) proposed that the human beard is
a costly signal of male competitive ability, as beards may be
easily grasped by rival males during fights. Therefore, a man
with a full beard may be advertising his confidence and higher
competitive ability, despite the apparent handicap of the
beard. Thus, beards may directly signal competitive ability to
rival males. Indeed, Freedman (1969) argued that beards in-
crease the perceived status of men and may increase the social
distance between rival men.
Intersexual selection via mate choice may favor ornaments as
indirect signals of genetic quality or as direct cues of fitness
(Darwin 1871;Andersson 1994;Hunt et al. 2004). If, as Zahavi
and Zahavi (1997) suggest, the human beard is a costly signal
of male competitive ability, then it may be preferred by female
mates as an indirect signal of fitness. Hamilton and Zuk
(1982) proposed that female preferences for male secondary
sexual adornments could be due to their signaling the male’s
ability to withstand or resist parasitic infection. Hair on the
face and body are potential localized breeding sites for dis-
ease-carrying ectoparasites (Nenoff et al. 2009;Weiss 2009).
Thus, hirsute men could be advertising their superior immune
system through possessing a trait that is immunologically costly.
Given that hirsuteism develops during adolescence under the
actions of androgens, and testosterone may have suppressant
effects on the immune system (Grossman 1985), males display-
ing androgen-dependent secondary sexual traits could be in-
directly advertising underlying genetic fitness to potential
mates (Folstad and Karter 1992).
Research on women’s sexual preferences for masculine
chest and trunk hair has shown cross-cultural differences.
Women from the United Kingdom stated a pronounced pref-
erence for masculine chest and trunk hair (Dixson et al. 2003).
A weaker preference for male body hair was found among
Bakossi women in Cameroon (Dixson, Dixson, Morgan,
et al. 2007), whereas women from China, New Zealand, and
the United States rated images lacking trunk hair as most
attractive (Dixson, Dixson, Li, et al. 2007,Dixson et al.
2010). Recently, Rantala et al. (2010) found that among
women in Finland, images of torsos depicting pronounced
chest hair were judged to be most attractive by postmeno-
pausal women and less attractive by younger women. Beards
augment perceptions of male masculinity, social maturity, con-
fidence, and age (Roll and Verinis 1971;Kenny and Fletcher
1973;Pancer and Meindl 1978;Wood 1986;Addison 1989;
Reed and Blunk 1990;Wogalter and Hosie 1991;Neave and
Shields 2008). Although women value these characteristics in
mates (Buss 1989;Penton-Voak and Perrett 2001), studies
of facial hair in relation to male facial attractiveness have
produced contradictory results. Thus, some studies have
found a full beard to be attractive to women (Freedman
1969;Pellegrini 1973;Reed and Blunk 1990), while others
have not (Feinman and Gill 1977;Wogalter and Hosie 1991;
Muscarella and Cunningham 1996). Neave and Shields
(2008) found that women rated male faces with light stubble
as most attractive; perceived age rose with increasing amounts
of facial hair, and a full beard was rated as looking most
dominant.
The equivocal results on male facial attractiveness and beard-
edness should be treated with caution, as the stimuli employed
in some of these studies may not accurately reflect mens’ faces
and beards as they appear in real life. One reason for this may
be that beards do not exist independently of other facial traits.
Facial expression plays an important role in many aspects of
social communication in human beings and in other anthro-
poids (Darwin 1872). Cross-cultural studies have shown that
many human populations share facial expressions indicative
of fundamental emotions, such as fear, surprise, anger, hap-
piness, sadness, and disgust (Ekman et al. 1969). It is thought
that such facial expressions are phylogenetically ancient in
humans (Ekman 1993;Schmidt and Cohn 2001). Morpholog-
ically very similar or identical facial expressions have also been
described in the great apes (Burrows et al. 2006;Vick et al.
2007). Researchers have suggested that in primates, the smile
originated as a rejection response to noxious stimuli (i.e.,
drawing back the corners of the mouth), then evolved into
a ritualized signal of fear and submission (i.e., a fear grimace)
before finally differentiating into graded fearful, nervous, and
genuinely happy smiles in humans (Andrew 1963;Van Hoof
1972). In many species of nonhuman primates, males have
striking secondary sexual adornments involving the face and
head (Dixson 1998;Dixson et al. 2005). As such, facial expres-
sions and secondary sexual adornments might act in concert
for display purposes.
Although studies of female preferences for male body hair
have included the preferences of people from indigenous as
well as Western cultures, research on perceptions of bearded-
ness have focused largely on the judgments of people of Euro-
pean descent from Western cultures. Any examination of the
signaling value of beards will be greatly strengthened through
establishing the similarities and differences in perceptions of
male beardedness cross-culturally. As such, we carried out this
research with participants of European descent in New Zea-
land (NZ) and with participants of Polynesian descent in Inde-
pendent Samoa. These cultures differ markedly in
socioeconomic status and exposure to modern mass media.
NZ is a modern industrialized country with a population of
more than 4 million people and has a high exposure to West-
ern popular culture. In contrast, Samoa is a chain of islands in
Western Polynesia with a population of 179 000. Compared
with NZ, Samoa has far less exposure to Western popular cul-
ture, such as billboards, fashion magazines, movies, and access
to the Internet is not widely available outside of the capital
Apia. Bearded and clean-shaven men from both cultures were
photographed posing with neutral, smiling, and angry facial
expressions. The aim of this study was to test how beardedness,
in concert with facial expressions indicative of anger and hap-
piness, influence perceptions of male attractiveness, social sta-
tus, age, and aggressiveness.
MATERIALS AND METHODS
Photographic stimuli
Ten NZ men of European descent (mean age = 23.50, standard
deviation [SD] = 3.57, range 20–30 years) and 9 Samoan men
(mean age = 23.00, SD = 2.12, range 20–27 years) were
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recruited for this study. The men from these 2 cultures did not
differ significantly in age (t
17
= 0.366, P= 0.713). Participants
were recruited with full beards, defined as not having shaved
or trimmed the face for at least 6 weeks. These men were
photographed with a full beard and then again when clean-
shaven posing neutral, smiling, and angry facial expressions
using a Canon PowerShot digital camera with a resolution of
8.0 megapixels. The camera was setup 150 cm from the par-
ticipant, and all photographs were taken under the same con-
trolled lighting. Figure 1 provides examples of the faces and
facial expressions used in NZ and Samoa.
The Facial Action Coding System (FACS: Ekman et al. 2002)
was used to produce photographs of men with standardized
angry and smiling facial expressions. FACS describes the
movement of groups of facial muscles or Action Units
(AUs). Forty-four AUs have been identified, 30 of which relate
to specified movements of suites of facial muscles and 14 that
are not specifically associated with anatomy (Kanade et al.
2000). FACS does not refer to movements that are specific
to an emotion, however, combinations of AUs can produce
posed facial expressions that are in turn perceived as expres-
sions of emotion (Ekman et al. 2002). In our study, we were
interested in whether facial hair plays a role in communicat-
ing 2 emotional states: happiness and anger. Therefore, we
used FACS to instruct participants to pose happy and angry
facial expressions.
The instructions for the movement of AUs were verbally
administered by a researcher, who posed the facial expressions
and provided examples from FACS (Ekman et al. 2002).
Figure 2 shows the AUs employed to pose an angry facial
expression in this study. First, a frowning eyebrow movement
requires movement of the corrugator supercilii and depressor
supercilii muscles. To achieve this pose, participants were
asked to draw their eyebrows medially and down (Figure
2A). An open eye requires movement of the levator palpebrae
superioris, and participants were asked to open their eyes
while frowning (Figure 2B). Open eyes were posed along with
a wrinkled nose, requiring the nasolabial furrow to be deep-
ened (Figure 2B). Participants were then asked to pull down
their lower lip, part their lips, and clench their teeth. This
sequence requires the movement of the depressor labii infe-
rioris, (Figure 2C). Participants repeated this combination of
AUs when clean-shaven and fully bearded (Figure 2D).
Questionnaires
Each questionnaire began with a cover sheet to collect demo-
graphic information from each participant (sex, age, and eth-
nicity). All questionnaires were submitted anonymously, and
participation was voluntary. NZ participants were interviewed
at Victoria University of Wellington, New Zealand. In the Sa-
moan sample, all the participants were Samoan citizens living
on Upolu island. All participants were interviewed individually
at their homes, in communal huts, or at farms using a flipbook
containing the photographs. Each photograph was cropped to
show only the face, from the top of the head to below the jaw-
line (Figure 1). This research was preapproved by the Human
Ethics Committee of Victoria University of Wellington and is
in accordance with the Helsinki Declaration of 1975. Partic-
ipants completed 4 studies, as detailed below.
Study 1 quantified women’s ratings of attractiveness of
men posing smiles with full beards and clean-shaven. The
photographs were presented individually, in a random order
and rated using a 6-point Likert Scale, where 0 = unattractive,
Figure 1
Examples of the facial expres-
sions used to test the effect of
the beard on perceptions of at-
tractiveness (A), aggressiveness
(B), and social status and per-
ceived age (C) in New Zealand
and Samoa.
Dixson and Vasey Beards, a secondary sexual trait in humans 483
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1 = only slightly attractive, 2 = moderately attractive, 3 = attrac-
tive, 4 = very attractive, and 5 = extremely attractive.
Study 2 measured men’s judgments of physical aggressive-
ness of bearded and clean-shaven men. Photographs of men
posing angry facial expressions were presented individually
in a random sequence and rated for aggressiveness using
a 6-point Likert Scale, where 0 = not aggressive, 1 = only slightly
aggressive, 2 = moderately aggressive, 3 = aggressive, 4 = very
aggressive, and 5 = extremely aggressive.
Study 3 assessed men’s and women’s judgments of social sta-
tus of men with beards or clean-shaven, posing neutral expres-
sions. Social status was defined as how likely the person in the
photograph was to have a high-ranking social position and
command respect over other men in the community. To sim-
plify this, after the definition of social status was explained to
participants, the word ‘‘importance’’ was used in the social sta-
tus scale, which was as follows: 0 = low importance, 1 = only
slightly important, 2 = moderately important, 3 = important,
4 = very important, and 5 = extremely important.
Study 4 assessed men’s and women’s perceived age (in years)
of men photographed posing neutral facial expression with
beards or clean-shaven.
For the NZ sample, participants were of European descent
and rated only the images of men who were of European
descent. Samoan participants rated only the photographs of
Samoan men. In Samoa, a linguistic interpreter, fluent in both
English and Samoan, was present to ensure that participants
understood the Likert Scales.
STATISTICAL ANALYSIS
The mean attractiveness (study 1), aggressiveness (study 2), so-
cial status (study 3), and perceived age (study 4) ratings of
clean-shaven and bearded faces were entered as dependent
variables in separate two-way repeated mixed measures analy-
ses of covariance (ANCOVAs). In each, ANCOVA culture
(Samoa vs. NZ) was the between-subjects fixed factor, bearded-
ness (bearded vs. clean-shaven) was the within-subjects re-
peated measures fixed factor, and participant’s age was
a covariate. For study 3 (social status) and study 4 (perceived
age), sex (male vs. female) was included as an additional
between-subjects fixed factor. Post hoc two-tailed paired sam-
ple t-tests were used to uncover which factors were driving
significant interactions within subjects. For interactions be-
tween subjects, post hoc independent samples t-tests were em-
ployed. For all independent samples t-tests, Levene’s test for
equality of variances was used prior to comparing the means.
If this test was significant (P,0.05), we have reported the
Figure 2
The FACS was used to pose an-
gry facial expressions. Partici-
pants were asked to draw
their eyebrows medially and
down (A), while retaining
open eyes and a wrinkled nose
(B). Participants were also
asked to part their lips while
drawing them down and
clenching their teeth (C). This
combination of movements
was repeated in the same par-
ticipants when clean-shaven
and fully bearded (D).
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results of a modified test in which an adjusted degrees of
freedom, test statistic, and Pvalue were calculated using the
Welch–Satterthwaite method. This calculation compares the
means of the 2 groups without assuming equality of variances.
All computations were made using PAWS Version 18 (SPSS
2009).
RESULTS
Study 1: the beard and perceived attractiveness
A total of 100 Samoan women (mean [M] = 21.36, SD = 3.30,
range = 18–33 years) and 129 NZ women (M= 20.38, SD =
3.63, range = 18–38) participated in this study. The Samoan
participants were significantly older than the NZ participants
(Levene’s test for equality of variances F= 0.029, P= 0.865;
t
227
=22.11, P= 0.036). Age was included as a covariate in
a two-way repeated mixed measures ANCOVA, in which attrac-
tiveness ratings was the dependent variable, culture (Samoa
vs. NZ) was the between-subjects fixed factor, and beardedness
(bearded vs. clean-shaven) was the within-subjects repeated
measures fixed factor.
The ANCOVA revealed a significant main effect of bearded-
ness (F
1,226
= 23.25, P,0.001, g
p2
= 0.093), so that women’s
attractiveness ratings were significantly higher for clean-
shaven than bearded men in both NZ (t
128
= 11.83, P,
0.001) and Samoa (t
99
= 12.01, P,0.001; Figure 3A). There
was a significant main effect of culture on the attractiveness
judgments (F
1,226
= 112.32, P,0.001, g
p2
= 0.332), so that
Samoan women’s attractiveness ratings were significantly high-
er, overall, for both clean-shaven and bearded men, compared
with those of NZ women (Levene’s test for equality of varian-
ces F= 14.62, P,0.001; t
169.223
=210.28, P,0.001). There
was a significant interaction between culture and beardedness
(F
1,226
= 12.53, P,0.001, g
p2
= 0.053), which reflects that
Samoan women gave higher scores than NZ women for clean-
shaven (Levene’s test for equality of variances F= 20.37, P,
0.001; t
158.774
=211.16, P,0.001) and bearded faces (Lev-
ene’s test for equality of variances F= 7.62, P= 0.006; t
183.814
=
26.92, P,0.001). There was no main effect of age (F
1,226
=
0.01, P= 0.917, g
p2
= 0.000). However, there was a significant
interaction between beardedness and age (F
1,226
= 3.99, P=
0.047, g
p2
= 0.017), which reflects a trend for older women
to judge bearded faces as more attractive than younger
women (Pearson Correlation: r= 0.120, N= 229, P= 0.07)
but not for clean-shaven faces (r= 0.034, N= 229, P= 0.605).
Study 2: the beard and perceived aggressiveness
In total, 111 NZ men (M= 20.86, SD = 3.57, range = 18–39
years) and 119 Samoan men (M= 28.55, SD = 11.02, range =
18–71 years) completed this study. Samoan men were signifi-
cantly older than the NZ men (Levene’s test for equality of
variances F= 79.00, P,0.001; t
144.004
=27.23, P,0.001). Age
was entered as a covariate in a two-way repeated mixed meas-
ures ANCOVA, where ratings of aggressiveness was
the dependent variable, culture (Samoa vs. NZ) was the be-
tween-subjects fixed factor, and beardedness (bearded vs.
clean-shaven) was the within-subjects repeated measures fixed
factor.
The ANCOVA revealed a significant main effect for bearded-
ness (F
1,227
= 66.37, P,0.001, g
p2
= 0.226). Men gave higher
aggressiveness ratings for bearded faces than clean-shaven
faces in both NZ (t
110
=218.31, P,0.001) and Samoa (t
118
=221.70, P,0.001; Figure 3B). There was a statistically sig-
nificant main effect of culture on aggressiveness ratings (F
1,227
= 58.93, P,0.001, g
p2
= 0.206), revealing that Samoan men’s
aggressiveness ratings were higher overall for both categories
of facial hair than those of the NZ men (Levene’s test for
equality of variances F= 20.66, P,0.001; t
191.573
=28.41,
P,0.001). There was also a significant interaction between
facial hair and culture (F
1,227
= 13.04, P,0.001, g
p2
= 0.054),
which reflects that Samoan men gave higher ratings than men
from NZ for clean-shaven faces (Levene’s test for equality of
variances F= 7.02, P= 0.009; t
206.204
=25.62, P,0.001) as well
as bearded faces (Levene’s test for equality of variances F=
8.96, P= 0.003; t
207.919
=29.10, P,0.001). There was
no significant main effect of age (F
1,227
= 0.004, P= 0.947,
g
p2
= 0.000), or a significant interaction between age and
beardedness (F
1,227
= 0.73, P= 0.394, g
p2
= 0.003).
Study 3: the beard and perceived social status
A total of 52 NZ men (M= 21.81, SD = 3.01, range = 18–28
years), 64 NZ women (M= 21.27, SD = 4.84, range = 18–42
years), 119 Samoan men (M= 28.55, SD = 11.02, range = 18–
71 years), and 100 Samoan women (M= 21.36, SD = 3.30,
range = 18–33 years) completed this study. Participant’s age
was entered as a dependent variable in a 2 culture (NZ vs.
Samoa) 32 sex (male vs. female) analyses of variance. This
revealed a significant interaction between culture and sex
(F
1,331
= 15.85, P,0.001, g
p2
= 0.046). Thus, age was entered
as a covariate, social status ratings was the dependent variable,
beardedness (bearded vs. clean-shaven) was the within-sub-
jects repeated measures fixed factor, and culture (NZ vs. Sa-
moa) and sex (male vs. female) were between-subjects fixed
factors in a two-way repeated mixed measures ANCOVA.
The ANCOVA revealed a significant main effect for bearded-
ness (F
1,330
= 10.47, P,0.001, g
p2
= 0.031). Bearded faces
received higher scores for social status than clean-shaven faces
(t
334
=214.14, P,0.001; Figure 4A). There was also a statis-
tically significant main effect of sex (F
1,330
= 13.85, P,0.001,
g
p2
= 0.040), so that men gave higher scores overall for both
Figure 3
(A) Mean attractiveness scores (61 SD) made by women for faces
posing smiling facial expressions when clean-shaven and bearded.
(B) Mean aggressiveness scores (61 SD) made by men for faces
depicting angry facial expressions when clean-shaven and bearded.
Dixson and Vasey Beards, a secondary sexual trait in humans 485
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clean-shaven and bearded faces than women (Levene’s test for
equality of variances F= 10.05, P= 0.002; t
317.108
= 4.25, P,
0.001). There was also a significant interaction between beard-
edness and sex (F
1,330
= 8.73, P= 0.003, g
p2
= 0.026), as men
gave higher social status ratings for bearded than clean-shaven
faces (t
170
= 13.16, P,0.001) as did women (t
163
= 7.28, P,
0.001). Men also gave higher social status ratings than women
for bearded (Levene’s test for equality of variances F= 2.92,
P= 0.088; t
333
= 5.02, P,0.001) but not clean-shaven
faces (Levene’s test for equality of variances F= 1.87, P=
0.172; t
333
= 1.08, P= 0.280). To further investigate the sex
difference in the ratings of bearded and clean-shaven faces,
we calculated the differential between social status ratings
within males and females by subtracting the ratings for
clean-shaven faces from those of bearded faces. An indepen-
dent samples t-test revealed that the differential was greater
among men compared with women (Levene’s test for equality
of variances F= 0.78, P= 0.379; t
333
= 3.67, P,0.001). There
were no main effects of culture (F
1,330
= 2.27, P= 0.133, g
p2
=
0.007) or age (F
1,330
= 1.79, P= 0.181, g
p2
= 0.005). There was
no statistically significant interaction between beardedness
and culture (F
1,330
= 1.21, P= 0.273, g
p2
= 0.004), beardedness
and age (F
1,330
= 0.79, P= 0.376, g
p2
= 0.002), culture and sex
(F
1,330
= 1.69, P= 0.195, g
p2
= 0.005), or any three-way inter-
action between beardedness, culture, or sex (F
1,330
= 0.005,
P= 0.942, g
p2
= 0.000).
Study 4: the beard and perceived age
The same participants who completed study 3 completed this
study. We ran a two-way repeated mixed measures ANCOVA
in which participant’s age was entered as a covariate, perceived
age ratings was the dependent variable, beardedness (bearded
vs. clean-shaven) was the within-subjects repeated measures
fixed factor, and culture (NZ vs. Samoa) and sex (male vs. fe-
male) were between-subjects fixed factors.
The ANCOVA revealed significant main effects for bearded-
ness (F
1,330
= 50.17, P,0.001, g
p2
= 0.132), culture (F
1,330
=
328.02, P,0.001, g
p2
= 0.498), and sex (F
1,330
= 27.13, P,
0.001, g
p2
= 0.076). The main effect of beardedness reflects
that beards were rated as looking significantly older by Sa-
moan men (t
118
=219.09, P,0.001), Samoan women (t
99
=220.08, P,0.001), NZ women (t
63
=211.46, P,0.001),
and NZ men (t
51
=22.99, P= 0.004; Figure 4B). The main
effect of culture reflects that NZ scores were higher overall
than Samoan scores (Levene’s test for equality of variances F=
2.72, P= 0.100; t
333
= 18.60, P,0.001). The main effect of sex
reflects that women’s scores were overall higher than men’s
(Levene’s test for equality of variances F= 14.30, P,0.001;
t
311.768
=24.56, P,0.001). There was a significant interaction
between beardedness and sex (F
1,330
= 21.55, P,0.001, g
p2
=
0.061), which reflects that women gave significantly higher
age ratings to both clean-shaven (Levene’s test for equality
of variances F= 4.65, P= 0.032; t
326.305
=22.43, P= 0.016)
and bearded (Levene’s test for equality of variances F= 5.23,
P= 0.023; t
318.126
=25.86, P,0.001) faces. There was also
a significant interaction between beardedness and culture
(F
1,330
= 85.30, P,0.001, g
p2
= 0.205), so that participants
from NZ gave higher ratings than participants from Samoa for
both clean-shaven (Levene’s test for equality of variances F=
0.07, P= 0.785; t
333
= 23.35, P,0.001) and bearded faces
(Levene’s test for equality of variances F= 3.50, P= 0.062; t
333
= 9.08, P,0.001). Finally, there was a significant three-way
interaction between beardedness, sex, and culture (F
1,330
=
6.69, P= 0.010, g
p2
= 0.020). These interactions reflect that
compared with women from Samoa, women from NZ rated
clean-shaven faces as older (Levene’s test for equality of var-
iances F= 7.83, P= 0.006; t
159.394
= 18.95, P,0.001) as well as
bearded faces (Levene’s test for equality of variances F= 0.25,
P= 0.620; t
162
= 9.40, P,0.001). Likewise, compared with
Samoan men, NZ men rated clean-shaven faces as older (Lev-
ene’s test for equality of variances F= 4.24, P= 0.041; t
80.199
=
13.78, P,0.001) as well as bearded faces (Levene’s test for
equality of variances F= 0.32, P= 0.572; t
169
= 3.45, P,0.001).
Women from NZ gave higher ratings than men from Samoa
for clean-shaven faces vs. bearded faces (Levene’s test for
equality of variances F= 11.38, P= 0.001; t
172.376
= 3.80, P,
0.001) and bearded faces vs. clean-shaven faces (Levene’s test
for equality of variances F= 3.44, P= 0.065; t
181
= 29.47, P,
0.001). Men from NZ gave higher scores than women from
Samoa for bearded versus clean-shaven faces (Levene’s test for
equality of variances F= 1.44, P= 0.232; t
150
= 14.99, P,
0.001) but not for clean-shaven versus bearded faces (Levene’s
test for equality of variances F= 0.03, P= 0.862; t
150
=21.04,
P= 0.298). There was no main effect of the participant’s
age (F
1,330
= 1.90, P= 0.169, g
p2
= 0.006) or any interaction
between facial hair and participant’s age (F
1,330
= 0.17,
P= 0.681, g
p2
= 0.001).
DISCUSSION
This study found that men and women from NZ and Samoa
judged neutral faces with beards as having higher social status
and being older than clean-shaven faces. Men also judged
bearded faces posing angry facial expressions as more aggres-
sive than clean-shaven faces. However, women rated the clean-
shaven smiling faces as more attractive than bearded faces. This
suggests that the beard plays a stronger role in intrasexual sig-
naling than in female mate preferences.
Figure 4
(A) Mean social status scores (61 SD) made by men and women for
faces depicting neutral facial expressions when clean-shaven and
bearded. (B) Mean perceived age scores (61 SD) made by men and
women for faces depicting neutral facial expressions when clean-
shaven and bearded.
486 Behavioral Ecology
by guest on January 13, 2017http://beheco.oxfordjournals.org/Downloaded from
Although beards do not directly improve fighting ability, as is
the case for weaponry used in male–male competition in many
animals (Emlen 2008), it has been suggested that they may
intimidate rival males by increasing perceptions of the size of
the jaw, overall length of the face, and by enhancing aggres-
sive and threatening jaw-thrusting behaviors (Guthrie 1970).
Among the Medlpa tribe of Papua New Guinea, when posing
an aggressive and threatening facial expression, men have
been observed to pull apart the beard with both hands
(Eibl-Eibesfeldt 1989). Similarly, beards are sometimes incor-
porated into gestural ‘beard jutting’’ threat displays, which
consist of flicking the back of the fingers of one hand under
the chin and outward, causing the beard to become erected
and thrust out toward the rival (Guthrie 1970;Morris 2002).
The beard may handicap men during fighting, as it might be
easily clutched by rival men (Zahavi and Zahavi 1997). Thus,
bearded men may be advertising confidence as well as supe-
rior fighting ability to male rivals. Several studies have found
that images of bearded men, posing neutral facial expres-
sions, are rated as highly self-confident (Pellegrini 1973)
and physically aggressive (Muscarella and Cunningham
1996;Neave and Shields 2008). The current study is the first
to show that the beard augments a threatening behavioral
display as bearded men with angry facial expressions received
significantly higher scores for aggressiveness compared with
clean-shaven faces in both NZ and Samoa. This suggests that
the beard plays an important role in intermale signaling of
threat and aggression.
Several authors have advanced the view that secondary sex-
ual adornments have evolved in mammals as ‘‘psychological
weapons’’ that act in concert with threatening or aggressive dis-
plays (Archer 2009;Darwin 1872;Guthrie 1970;Hingston
1933). Central to this view, however, is that if a trait or behav-
ior has evolved as a signal, it should, in turn, affect the behav-
ior of others (Maynard Smith and Harper 2003). As an
example, consider songbirds, where if a song is to be classified
as an aggressive signal, it should be augmented in aggressive
contexts, predict aggressive intent, and elicit a response from
the recipients of the display (Searcy and Beecher 2009). In
humans, anger is a display of aggression and threat that may
curtail the behavior of others (Averill 1983). When people
view images of angry faces, neurological research has shown
augmented activity in the orbitofrontal and anterior cingulate
cortex with the increasing intensity of angry facial expressions,
which Blair et al. (1999) suggest is a response that encourages
behavioral extinction in the recipient of the signal. In this
study, we tested the extent to which facial expressions and
beards act in concert in the perceptions of an aggressive
threatening facial expression. Research on male vocal pitch
has shown that lower vocal pitch augments perceptions of
dominance and aggression in men (Puts et al. 2006,2007),
and men who judge themselves as physically dominant lower
their vocal pitch in response to other male competitors (Puts
et al. 2006). Similar studies testing the role of beardedness in
intrasexual aggressiveness signaling during competitive sce-
narios would be valuable to further understand the signalling
value of facial hair. For example, one might predict based on
the neurological studies, that men will exhibit greater orbito-
frontal and anterior cingulate cortex activation in response to
bearded angry facial expressions than when viewing clean-
shaven angry faces.
It has been suggested that facial hair decreases a male’s per-
ceived social status because it is associated with traits such as
vagrancy (Morris 2002). Our results fail to provide support
for this perspective, as participants rated bearded men as hav-
ing higher social status than clean-shaven men. Furthermore,
we found that men ascribed higher ratings for perceived
social status to bearded faces than women. Our results are
consistent with other studies that have shown the beard aug-
ments perceptions of social dominance and status (Addison
1989;Muscarella and Cunningham 1996;Neave and Shields
2008). Further evidence that beardedness is associated with
augmented social status was found in a study of male aca-
demic staff at Universities in the United Kingdom, where Pro-
fessors were significantly more heavily bearded than Senior
Lecturers, Lecturers, and Research Fellows (Carter and
A
˚stro
¨m 2004). These findings along with those of the current
study suggest that dominant men may grow facial hair in
order to effectively signal their social status and dominance.
Testosterone dependent traits may augment social domi-
nance (Mazur and Booth 1998) as well as aggressive displays
(Archer 2009), and there is growing evidence that sexual di-
morphism in craniofacial features and vocal pitch reflects
men’s actual physical strength (Sell et al. 2009,2010). Among
the Tsimane’ forager farmers of Beni, Bolivia, men and
women accurately assessed physical dominance (measured us-
ing midarm circumference) from photographs of the face
(Undurraga et al. 2010). Furthermore, greater dominance
and prestige among male Tsimane’ are associated with more
surviving offspring and more mating opportunities (Von
Rueden et al. 2010). Beardedness appears to signal elevated
social status, dominance, and the communication of aggres-
sive intent. However, whether or not the beard honestly adver-
tises men’s actual strength or is associated with greater
reproductive success, as are other masculine traits, remains
to be determined.
Given that a beard makes a man look older than his real age
and women typically prefer a partner who is 2–3 years older
than themselves (Buss 1989;Kenrick and Keefe 1992), it
seems reasonable to suspect that beards may enhance male
facial attractiveness to women. However, clean-shaven faces
received significantly higher scores for attractiveness than
bearded faces in both NZ and Samoa. Some previous studies
have found that bearded men are rated as more socially
mature, sincere, masculine, self-confident, and courageous
than clean-shaven faces (Kenny and Fletcher 1973;Pellegrini
1973;Neave and Shields 2008). While women may value all
of these characteristics in male mates, studies of female pref-
erences for male beardedness have produced conflicting re-
sults. Some studies have concluded that beards enhance
attractiveness to women (Freedman 1969;Pellegrini 1973;
Reed and Blunk 1990), whereas in other studies the opposite
effect has been observed (Feinman and Gill 1977;Wogal te r
and Hosie 1991;Muscarella and Cunningham 1996). As well
as beards, androgens drive sexually dimorphic traits such as
a large jaw, narrow eyes, a pronounced brow ridge, and a lon-
ger face (Weston et al. 2007;Thayer and Dobson 2010). Men
displaying these masculine traits are ranked as less ‘‘warm,’
honest and cooperative (Penton-Voak and Perrett 2001), and
less trustworthy (Stirrat and Perrett 2010) and are more phys-
ically aggressive (Carre´ et al. 2009). Some studies have found
that facial masculinity does not augment perceptions of at-
tractiveness to women (Perrett et al. 1998;Swaddle and
Reierson 2002;Neave et al. 2003). However, in mate choice,
the fitness of a phenotype depends not only on the pheno-
type but also on the context. Female choice may be highly
variable, due to individual motivation and the availability of
mates carrying preferred traits (Jennions and Petrie 1997),
suggesting that male ornamentation is maintained via con-
text-specific female choice. Recent cross-cultural studies
found that women in countries with lower overall health
and higher income inequality judge masculine faces to be
more attractive than in countries with better health care
and greater income stability (Debruine et al. 2010,2011;
Brooks et al. 2011). The strength of female preferences for
beardedness may also differ cross-culturally as a result of
Dixson and Vasey Beards, a secondary sexual trait in humans 487
by guest on January 13, 2017http://beheco.oxfordjournals.org/Downloaded from
demographic variables, and future studies testing this hy-
pothesis would be valuable.
A further source of context-specific variation in mate choice
concerns women’s preferences for androgen-dependent traits
across the menstrual cycle. It has been found that women in
the fertile phase of the menstrual cycle have a greater prefer-
ence for masculine facial, bodily, and vocal features than
women interviewed at other points of the menstrual cycle
(Gangestad and Thornhill 2008). These traits may be energet-
ically and immunologically costly and only sustainable by
those males of higher genetic quality or competitive ability
(Folstad and Karter 1992). Given that the growth of terminal
hairs on the face and body is androgen-dependent (Randall
2008) and by consequence might incur physiological costs for
males, it is possible that female preferences for body hair and
beardedness will vary depending upon the phase of the men-
strual cycle. Rantala et al. (2010) showed that women at the
low-fertility phase of the menstrual cycle stated a higher pref-
erence for male torsos with pronounced body hair than
women at the high-fertility phase of the menstrual cycle. In-
terestingly, this study also revealed that postmenopausal
women had a higher preference for body hair than premen-
opausal women. It will be important for future studies to
uncover the extent to which women’s preferences for beard-
edness vary due to menstrual cycle phase and reproductive
status.
For centuries, fashion, religious values, and political agen-
das have shaped the social significance of man’s facial hair
(Peterkin 2001;Reynolds 1949). A study, quantifying styles
of facial hair (e.g., mustaches, sideburns, and full beards) in
men photographed for the Illustrated London News between
1842 and 1971, showed that the popularity of facial hair and
particular styles of facial hair, fluctuated over time (Robinson
1976). In the current study, it is possible that women from
Wellington, New Zealand, which is a modern industrialized
city with high exposure to ‘‘Western’’ popular media, rated
clean-shaven faces as more attractive than bearded faces be-
cause it is currently more fashionable for men to be clean-
shaven in Western society. However, in Samoa, there is far less
exposure to Western popular media. For example, it is diffi-
cult, even in the capital of Apia, to find magazines of any sort
(including fashion magazines) that can be easily acquired in
Western societies. Equally, there are no large billboards adver-
tising fashion, and there is only one movie theater in the
entire country. Outside of the capital, access to the Internet
is sparse. Nevertheless, like NZ women, Samoan women also
rated clean-shaven faces as more attractive. Indeed, Samoan
women’s attractiveness ratings for clean-shaven male faces
were higher than those of NZ women. However, in Samoa
the presence of Missionaries may have brought Western ideol-
ogies of dress and influenced men’s shaving habits (Mageo
1994). Thus, although preferences for clean-shaven faces ap-
pear to be cross-culturally robust, it would be beneficial to test
this hypothesis in a culture where beards are commonly worn.
It is conceivable that secondary sexual traits such as the
beard in Homo sapiens were present in the ancestral hominids.
However, the fossil record cannot answer this question, as
cutaneous tissue does not fossilize. Thus, comparative studies
of human beings and extant nonhuman primates may shed
light on the possible functions of visually conspicuous second-
ary sexual traits in threat or dominance displays (Dixson et al.
2005). For example, mature male gorillas (silverbacks) are
larger, more muscular than females, adorn a gray covering
on their backs, and an adipose crest on top of the head.
Adipose crests are largest in those males having the most
females in their one-male units (Caillaud et al. 2008). In the
orangutan, adult males develop full expression of their
‘cheek flanges’’ and beards only when they achieve dominant
positions in the social system (Galdikas 1985;Kingsley 1982;
Utami Atmoko and Van Hoof 2004). Male mandrills (Mandril-
lus sphinx) exhibit spectacular red and blue facial coloration,
the red coloration being most pronounced in dominant males
having higher testosterone levels (Wickings and Dixson 1992;
Setchell and Dixson 2001). Dominant male hamadryas ba-
boons (Papio hamadryas) also develop large androgen-depen-
dent capes of hair that appear to be sexually selected as
a dominance signal between males (Zuckerman and Parkes
1939;Kummer 1990). Although secondary sexual facial color-
ation and capes of hair in nonhuman primates are not strictly
homologous to the beards of the human male, they may have
arisen via similar selective mechanisms. Such traits are visually
conspicuous and communicate an individual male’s age and
dominance status. Compared with many nonhuman primates,
men exhibit relatively well-developed secondary sexual traits
(e.g., facial and body hair) such as those that occur in polyg-
ynous species (Dixson 1998;Dixson et al. 2005). Although
further evidence is required, the results of the present study
suggest that the human beard plays an important role intra-
sexually as a signal of age, social status, and aggressiveness.
FUNDING
New Zealand International Doctoral Scholarship (to B.J.D.);
Victoria University of Wellington (to B.J.D.); the University
of Lethbridge (to P.L.V.); the Natural Sciences and Engineer-
ing Research Council of Canada (to P.L.V.).
We wishto thank VaasatiaPoloma Komiti, Alatina Ioelu, Trisha Tuiloma,
Avalogo Togi A. Tunupopo, the Kuka family of Savai’i, the National
University of Samoa, the Government of Samoa, and all of the individ-
uals who agreed to participate in our study.
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... Rahman & Wilson, 2003). However, the existing literature predominantly relies on European standards, making technical curriculum approaches in Asian countries often less compatible with local anthropometric proportions (Dixson & Vasey, 2012;Dyer et al., 2011). In this context, the present study aims to provide the empirical data needed to strengthen the relevance of technical vocational education in Indonesia, particularly enabling learners to depict human proportions consistent with local characteristics (Rosa & Orey, 2015). ...
... To ensure the validity and reliability of the research findings, data triangulation was applied by comparing the results of this study with anthropometric data from previous research in Southeast Asia. Standardized measurement protocols were implemented to ensure consistency in data collection and reduce bias (Bhasin et al., 2001;Dixson & Vasey, 2012). Furthermore, the research findings were rigorously reviewed by experts in the fields of anthropometry and vocational education, ensuring their accuracy and relevance in academic and practical contexts. ...
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This study aims to identify the anatomical body proportions of Malay-Indonesian males as an essential reference in vocational education, particularly for developing curricula in technical drawing and engineering illustration. Using a content analysis method, the study sample consists of 1,000 Malay men from various provinces in Indonesia. Data were collected through photographic documents and analyzed based on age, gender, and ethnicity. The ratio of body to head size was measured to identify relevant characteristics of body proportions. The results show that Malay male body proportions are shorter compared to Europeans; while the European body proportion is eight times the head size, the Malay proportion is seven times the head size. These findings have important implications for vocational education in designing curricula and instructional materials that are more accurate and relevant to local anthropometric characteristics. Understanding these body proportions enables vocational institutions to develop more effective programs in technical drawing and design education that are contextually appropriate. This research contributes to improving the quality of vocational education by providing empirical data as a reference for more culturally relevant and contextually appropriate drawing techniques and training.
... Compared to clean-shaven faces, beards increase ratings of male age (Dixson & Vasey, 2012), masculinity (Dixson & Brooks, 2013), dominance (Neave & Shields, 2008), strength (Gray et al., 2020;Nelson et al., 2019) and aggressiveness (Addisson, 1989;Muscarella & Cunningham, 1996). These social judgments increase linearly with the quantity of facial hair (Dixson & Brooks, 2013;Neave & Shields, 2008) via emphasising the midface and jaw (Dixson et al., 2017a). ...
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... In our sample, only eight men wear a beard (and thirteen a moustache), so the conclusiveness is limited from the outset. This is all the more true as there are quite di erent beard styles and these can have di erent e ects depending on the individual face type, which is certainly one of the reasons for the rather inconsistent ndings on the impact of facial hair (Dixson and Brooks, 2013;Dixson and Vasey, 2012;Povoa et al., 2024). The absolute head Tilt shows a positive correlation with Status, which is maintained even after controlling for Age (.38,.36 in order to demonstrate this, an experimental approach is required in which the hair status is systematically manipulated. ...
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