ArticlePDF Available


Red coloration is a sexually selected, testosterone-dependent signal of male quality in a variety of animals, and in some non-human species a male's dominance can be experimentally increased by attaching artificial red stimuli. Here we show that a similar effect can influence the outcome of physical contests in humans--across a range of sports, we find that wearing red is consistently associated with a higher probability of winning. These results indicate not only that sexual selection may have influenced the evolution of human response to colours, but also that the colour of sportswear needs to be taken into account to ensure a level playing field in sport.
NATURE|Vol 435 | 19 May 2005
Red enhances human performance in contests
Signals biologically attributed to red coloration in males may operate in the arena of combat sports.
Red coloration is a sexually selected, testos-
terone-dependent signal of male quality in a
variety of animals
, and in some non-human
species a males dominance can be experimen-
tally increased by attaching artificial red
. Here we show that a similar effect can
influence the outcome of physical contests in
humans — across a range of sports, we find
that wearing red is consistently associated with
a higher probability of winning. These results
indicate not only that sexual selection may
have influenced the evolution of human
response to colours, but also that the colour of
sportswear needs to be taken into account to
ensure a level playing field in sport.
Although other colours are also present in
animal displays, it is specifically the presence
and intensity of red coloration that correlates
with male dominance and testosterone
. In humans, anger is associated with a
reddening of the skin due to increased blood
, whereas fear is associated with
increased pallor in similarly threatening situa-
. Hence, increased redness during
aggressive interactions may reflect relative
dominance. Because artificial stimuli can
exploit innate responses to natural stimuli
we tested whether wearing red might
influence the outcome of physical contests
in humans.
In the 2004 Olympic Games, contestants in
four combat sports (boxing, tae kwon do,
Greco–Roman wrestling and freestyle
wrestling) were randomly assigned red or blue
outfits (or body protectors). If colour has no
effect on the outcome of contests, the number
of winners wearing red should be statistically
indistinguishable from the number of winners
wearing blue. However, we found that for
all four competitions, there is a consistent
and statistically significant pattern in which
contestants wearing red win more fights
4.19, d.f.1, P0.041; Fig. 1a). This
result is remarkably consistent across rounds
in each competition, with 16 of 21 rounds hav-
ing more red than blue winners, and only four
rounds having more blue winners (sign test,
P0.012). The effect is the same across the
weight classes in each sport: 19 of 29 classes
had more red winners, with only six classes hav-
ing more blue winners (sign test, P0.015).
(For methods, see supplementary information.)
Given the undoubted role of other factors,
such as skill and strength, it is likely that the
red advantage will determine the outcome
only in relatively symmetric contests. That is,
wearing red presumably tips the balance
between losing and winning only when other
factors are fairly equal. We found that this is
indeed the case: only in contests between indi-
viduals of similar ability were there signifi-
cantly more red than blue winners (
d.f.1, P0.014), with the red advantage
seeming to decline as asymmetries in compet-
itive ability increase (Fig. 1b). Hence, although
the effect is significant for the pooled data
shown in Fig. 1a, this is due principally to the
results for relatively symmetric contests.
These results indicate that artificial colours
may influence the outcome of physical con-
tests in humans. A preliminary analysis of the
results of the Euro 2004 international soccer
tournament, in which teams wore shirts of dif-
ferent colours in different matches, suggests
that wearing red may also bestow an advantage
in team sports and when opponents wear
colours other than blue. We compared the per-
formance of five teams that wore a predomi-
nantly red shirt against their performance
when wearing a different shirt colour (four
played their other matches in white, one in
blue). We found that all five had better results
when playing in red (paired t-test, t3.15,
d.f.4, P0.034), largely as a result of scoring
more goals (t2.98, d.f.4, P0.041)
(further details are available from the authors).
Hence, colour of sportswear may affect out-
comes in a wide variety of sporting contexts.
Colour is thought to influence human
mood, emotions and expressed aggression, and
is a recognized element of signalling in com-
petitive interactions in many non-human
species. But it has not hitherto been suspected
to be a factor in human contests. Given the
ubiquity of aggressive competition throughout
human societies and history, our results sug-
gest that the evolutionary psychology of colour
is likely to be a fertile field for further investiga-
tion. The implications for regulations govern-
ing sporting attire may also be important.
Russell A. Hill, Robert A. Barton
Evolutionary Anthropology Research Group,
University of Durham, Durham DH1 3HN, UK
1. Milinski, M. & Bakker, T. C. M. Nature 344, 330–333
2. Waitt, C. et al. Proc. R. Soc. Lond. B 270, S144–S146 (2003).
3. Setchell, J. M. & Wickings, E. J. Ethology 111, 25–50
4. Pryke, S. R., Andersson, S., Lawes, M. J. & Piper, S. E.
Behav. Ecol. 13, 622–631 (2002).
5. Andersson, S., Pryke, S. R., Ornborg, J., Lawes, M. J. &
Andersson, M. Am. Nat. 160, 683–691 (2002).
6. Cuthill, I. C. et al. Proc. R. Soc. Lond. B 264, 1093–1099
7. Drummond, P. D. & Quah, S. H. Psychophysiology 38,
190–196 (2001).
8. Darwin, C. The Expression of the Emotions in Man and
Animals (Murray, London, 1872).
9. Drummond, P. D. Pers. Indiv. Diff. 23, 575–582 (1997).
10. Ryan, M. J. in Behavioural Ecology (eds Krebs, J. R. &
Davies, N. B.) 179–202 (Blackwell Science, Oxford, 1997).
doi: 10.1038/435293a
Supplementary information accompanies this
communication on Natures website.
Competing financial interests: declared none.
Figure 1 | Influence of colour of sporting attire on the outcome of competitive sports. a,Proportion of
contests in Olympic combat sports won by competitors wearing red (right bars) or blue (left bars)
outfits for all sports combined and for the individual sports of boxing (Box), tae kwon do (TKD),
Greco-Roman wrestling (G–R W) and freestyle wrestling (Free W).
b, Proportion of contests won by
competitors wearing red or blue given different degrees of relative ability (asymmetry) in the two
competitors in each bout. No significant differences exist between the number of red and blue wins
for contests with small (
2.21, d.f.1, P0.14), medium (
0.47, d.f.1, P0.50) or large
asymmetries (
0.21, d.f.1, P0.64) in competitive ability. Black lines at 0.5 indicate the expected
proportion of wins by red or blue under the null hypothesis that colour has no effect on contest
outcomes. For details of data collection and analyses, see supplementary information.
Degree of asymmetry
Small Medium Large
Proportion of contests won
NoneAll Box TKD G–R W Free W
19.5 brief comms MH 13/5/05 9:53 AM Page 293
© 2005
© 2005 Nature Publishing Group
... Of particular interest for this work is the analysis of an individual's relationship with society [28,30]. Some studies include the evaluation of style as part of the study of nonverbal communication [29,[31][32][33][34][35][36]. ...
Full-text available
Market segmentation is a crucial marketing strategy that involves identifying and defining distinct groups of buyers to target a company’s marketing efforts effectively. To achieve this, the use of data to estimate consumer preferences and behavior is both appropriate and adequate. Visual elements, such as color and shape, in advertising can effectively communicate the product or service being promoted and influence consumer perceptions of its quality. Similarly, a person’s outward appearance plays a pivotal role in nonverbal communication, significantly impacting human social interactions and providing insights into individuals’ emotional states. In this study, we introduce an innovative deep learning model capable of predicting one of the styles in the seven universal styles model. By employing various advanced deep learning techniques, our models automatically extract features from full-body images, enabling the identification of style-defining traits in clothing subjects. Among the models proposed, the XCEPTION-based approach achieved an impressive top accuracy of 98.27%, highlighting its efficacy in accurately predicting styles. Furthermore, we developed a personalized ad generator that enjoyed a high acceptance rate of 80.56% among surveyed users, demonstrating the power of data-driven approaches in generating engaging and relevant content. Overall, the utilization of data to estimate consumer preferences and style traits is appropriate and effective in enhancing marketing strategies, as evidenced by the success of our deep learning models and personalized ad generator. By leveraging data-driven insights, businesses can create targeted and compelling marketing campaigns, thereby increasing their overall success in reaching and resonating with their desired audience.
... In general, a red color, which has a large wavelength, stimulates physical performance (Hill and Barton, 2005). Red can convey the urgency and safety critical aspect of the TOR, while colors as blue would suggest a lower urgency (Friedrich and Vollrath, 2022). ...
Full-text available
Introduction SAE Level 3 is known as conditional driving automation. As long as certain conditions are met, there is no need to supervise the technology and the driver can engage in non-driving related tasks (NDRTs). However, a human driver must be present and alert to take over when the automation is facing its system limits. When such an emergency takes place, the automation uses the human machine interface (HMI) to send a take-over request (TOR) to the driver. Methods We investigated the influence of a color themed HMI on the trust and take-over performance in automated vehicles. Using a driving simulator, we tested 45 participants divided in three groups with a baseline auditory HMI and two advanced color themed HMIs consisting of a display and ambient lighting with the colors red and blue. Trust in automation was assessed using questionnaires while take-over performance was assessed through response time and success rate. Results Compared to the baseline HMI, the color themed HMI is more trustworthy, and participants understood their driving tasks better. Results show that the color themed HMI is perceived as more pleasant compared to the baseline HMI and leads to shorter reaction times. Red ambient lighting is seen as more urging than blue, but HMI color did not significantly affect the general HMI perception and TOR performance. Discussion Further research can explore the use of color and other modalities to express varying urgency levels and validate findings in complex on road driving conditions.
... More recently, with their review of psychological literature, Elliot and Maier [7] showed that colour impacts people's affect, cogniCon, and behavior. Among other things, colour is known to influence consumers' behaviour [31] as well as athletes' performances in sport compeCCons [17]. ...
Full-text available
User ratings are widely used in web systems and applications to provide personalized interaction and to help other users make better choices. Previous research has shown that rating scale features and user personality can both influence users' rating behaviour, but relatively little work has been devoted to understanding if the effects of rating scale features may vary depending on users' personality. In this paper, we study the impact of scale granularity and colour on the ratings of individuals with different personalities, represented according to the Big Five model. To this aim, we carried out a user study with 203 participants, in the context of a web-based survey where users were assigned an image rating task. Our results confirm that both colour and granularity can affect user ratings, but their specific effects also depend on user scores for certain personality traits, in particular agreeableness, openness to experience and conscientiousness.
We perceive color everywhere and on everything that we encounter in daily life. Color science has progressed to the point where a great deal is known about the mechanics, evolution, and development of color vision, but less is known about the relation between color vision and psychology. However, color psychology is now a burgeoning, exciting area and this Handbook provides comprehensive coverage of emerging theory and research. Top scholars in the field provide rigorous overviews of work on color categorization, color symbolism and association, color preference, reciprocal relations between color perception and psychological functioning, and variations and deficiencies in color perception. The Handbook of Color Psychology seeks to facilitate cross-fertilization among researchers, both within and across disciplines and areas of research, and is an essential resource for anyone interested in color psychology in both theoretical and applied areas of study.
Nudge theory, a field of economics, aims to gently induce desirable behavior in humans and has been primarily applied to personal finance and public policy issues. In this study, we extended nudge theory to the design field by inductively deriving specific nudge design strategies that can be applied to retail space branding. To this end, nudge design examples were collected, and from them, nudge design keywords were extracted. Then, these keywords were categorized according to the five experiential marketing modules: sense, feel, think, act, and relate. From the keywords, we derived 30 nudge design strategies for retail space branding. Finally, the applicability of these strategies was tested through case studies of well-known brand stores with links to existing literature. Space branding design is a comprehensive domain where environmental, graphic, and product design come together and where nudge design could be effectively applied. The results of this study might be used as a checklist in a retail project and serve as a communication tool between marketers and designers.
Full-text available
Color is associated with gender information (e.g., red-female). This study aimed to investigate whether the color red could influence the categorization of human bodies by sex. Visual stimuli were created using body silhouettes with varying along the waist-to-hip ratio from female to male perceptions. These stimuli were presented in conjunction with red, green, and gray colors, which were used either as body color (Experiment 1) or background color (Experiment 2). Participants were instructed to categorize the sex of the body stimuli as either male or female by pressing labelled keys. The results revealed that the color red had distinct effects on body perception, contingent on its role as a body color or background color. Specifically, when used as a body color, red induced a feminine body perception, whereas as a background color, it leaned towards a perception of masculinity. These findings highlight the significance of color cues in shaping gender-related body bias.
Full-text available
AN important problem in evolutionary biology since the time of Darwin has been to understand why females preferentially mate with males handicapped by secondary sexual ornaments1-3. One hypothesis of sexual selection theory is that these ornaments reliably reveal the male's condition4-6, which can be affected for example by parasites4,7-13. Here we show that in the three-spined stickleback (Gasterosteus aculeatus) the intensity of male red breeding coloration positively correlates with physical condition. Gravid females base their active mate choice on the intensity of the male's red coloration. Choice experiments under green light prevent the use of red colour cues by females, and males that were previously preferred are now chosen no more than randomly, although the courtship behaviour of the males remains unchanged. Parasitieation causes a deterioration in the males' condition and a decrease in the intensity of their red coloration. Tests under both lighting conditions reveal that the females recognize the formerly parasitized males by the lower intensity of their breeding coloration. Female sticklebacks possibly select a male with a good capacity for paternal care14 but if there is additive genetic variation for parasite resistance, then they might also select for resistance genes, as proposed by Hamilton and Zuk4.
Full-text available
Carotenoid-based plumage ornaments are typically considered to be sexually selected traits, functioning as honest condition-dependent signals of phenotypic quality, but few studies have addressed the function of carotenoid color variation in male contest competition. Using two experiments, we investigated the status signaling function of the variable (ranging from yellow to red) carotenoid throat patch (collar) in the polygynous, sexually dimorphic red-collared widowbird (Euplectes ardens). First, we tested if the red collar functions as a dominance signal by painting spectrometrically controlled collar patches onto the brown plumage of nonbreeding males and staging dyadic male contests over food resources. Red-collared males dominated orange males, which in turn dominated the control brown and novel blue collars. Red dominance persisted when the collar manipulations were reversed within dyads and also when tested against testosterone implanted males. In the second experiment the collar size and color of breeding males were manipulated in the field before and after territories were established. All males with enlarged red and most with enlarged orange or reduced red collars obtained territories, whereas most males with reduced orange and all with blackened (removed) collars failed to establish or retain territories. In addition, among the territorial males, those with reduced signals defended smaller territories, received more intrusions, and spent more time in aggressive interactions. Redness and, to a lesser extent, size of the carotenoid ornament both seem to independently indicate male dominance status or fighting ability in male contest competition. Copyright 2002.
Full-text available
Sexual displays often involve several different ornamental traits. Yet most indicator models of sexual selection based on a single receiver (usually a choosy female) find that multiple handicap signals should be unstable. Here we study reasons for this contradiction, analyzing signal function, signal content, and trade-offs between signals in the polygynous red-collared widowbird Euplectes ardens. Males have both a long, graduated tail and a red carotenoid collar badge. Territory-holding "residents" have slightly shorter tails than the nonbreeding "floaters," but their carotenoid collars are 40% larger, and they have (on the basis of reflectance spectrometry and objective colorimetry) a 23-nm more long-wave ("redder") hue than floaters. This corroborates experimental evidence that the red collar is selected by male contest competition, whereas female choice is based almost exclusively on male tail length. Tail length is negatively correlated with the carotenoid signal, which together with body size and condition explains 55% of the variation in tail length. The trade-off in tail length and carotenoid investment is steeper among residents, suggesting an interaction with costs of territory defense. We propose that the "multiple receiver hypothesis" can explain the coexistence of multiple handicap signals. Furthermore, the trade-off between signal expressions might contribute to the inverse relation between nuptial tail elongation and coloration in the genus Euplectes (bishops and widowbirds).
Where individuals contest access to a resource, escalated physical fighting presents a risk to all involved. The requirement for mechanisms of conflict management has led to the evolution of a variety of decision rules and signals that act to reduce the frequency of aggression during competitive encounters. We examined strategies of conflict management in male mandrills (Mandrillus sphinx) living in two semi-free-ranging groups in Gabon. Adult male mandrills are large (31 kg), with long canines, making the costs of conflict potentially very high. We found that males formed dominance hierarchies, but that male–male relationships were characterized by avoidance, appeasement and ignoring. Fights were rare, but could result in death. Examination of the relationship between dominance and signaling showed that males use facial and gestural signals to communicate dominance and subordinance, avoiding escalated conflict. Male mandrills also possess rank-dependent red coloration on the face, rump and genitalia, and we examined the hypothesis that this coloration acts as a ‘badge of status’, communicating male fighting ability to other males. If this is the case, then similarity in color should lead to higher dyadic rates of aggression, while males that differ markedly should resolve encounters quickly, with the paler individual retreating. Indeed, appeasement (the ‘grin’ display), threats, fights and tense ‘stand-off’ encounters were significantly more frequent between similarly colored males, while clear submission was more frequent where color differences were large. We conclude that male mandrills employ both formal behavioral indicators of dominance and of subordination, and may also use relative brightness of red coloration to facilitate the assessment of individual differences in fighting ability, thereby regulating the degree of costly, escalated conflict between well-armed males.
The face usually flushes with rage but can also become pallid during seemingly similar emotional experiences. To investigate this paradox, 200 respondents rated their expected facial colour and the intensity of anger, fear and embarrassment to a range of questionnaire items that involved interpersonal threat or conflict, and also completed questionnaires on blushing propensity, anger expression, facial pallor and fear of injury. Respondents associated flushing with anger and pallor with fear, and reported a propensity for facial flushing, linked with blushing, or a propensity for pallor across a range of threatening and distressing situations. These findings suggest that facial colour during threatening interpersonal interactions may be influenced by fear as well as anger cues which depend, at least in part, on personality attributes.
The arbitrary assignment of different coloured leg bands to zebra finches (Taeniopygia guttata) has profound effects on mate preference, reproductive success, mortality rates, parental investment and sex ratio. Choice chamber experiments indicate that the effect is mediated by altered attractiveness to members of the opposite sex. Effects on intrasexual dominance are more equivocal. We present two experiments which demonstrate significant effects of band colour on behavioural dominance (red bands are more dominant than light green bands) and the resulting diurnal pattern of gain in mass, fat, and seeds stored in the crop. Consistent with the literature on dominance and strategic regulation of body mass in other species, subordinate (green-banded) birds maintain higher fat reserves at dawn, but dominant (red-banded) birds show the highest overall daily mass gains. The lack of obvious effects of band colour on dominance in previous studies may lie in the degree to which food can be monopolized by particular individuals.
Blood pressure, heart rate, and changes in facial and finger blood flow were monitored in 24 male Chinese and 24 male Caucasians while they described anger-provoking incidents and read out neutral material, either loudly and rapidly or softly and slowly. Describing the incidents loudly and rapidly heightened anger ratings and enhanced digital vasoconstriction but not blood pressure or heart rate; however, anger enhanced blood pressure during soft, slow speech. Facial blood flow increased during anger expression, irrespective of speech style, but decreased when neutral material was read out. The findings suggest that an increase in facial blood flow reduces peripheral vascular resistance during anger expression, and that baroreflexes attenuate increases in heart rate and blood pressure. Racial background did not influence subjective reports or physiological responses, possibly because the procedure did not draw strongly enough on cultural taboos.