ElectronicSupplementaryMaterials

Examplesofthefacialhairstimuli

Figure S1. An example of the facial hair stimuli used in this study. Images show one individual from each of the four categories of facial hair distribution (very light, light, medium, and heavy) in front and profile views with ten days of natural beard growth (above) and when clean-shaven (below).

IndividualdifferencesinpreferencesforbeardsWefittedsexofparticipant(male,female)andsexualorientation(attractedtomen,notattractedtomen)asbinaryfixedfactors,andcountryofresidenceasarandomfactor,plusallinteractionsbetweenthesefactorsinaGeneralLinearModel.Weremoved,instepwisefashion,the3-wayinteraction,andtheSexxCountryandOrientationxCountryinteractions,astheyallhadnegligibleeffectsonthemodel(atremovalallF<1,P>0.49).Sex(F1,4425=29.27,P<0.001),Orientation(F1,4425=14.57,P<0.001)andCountry(F1,4425=1.72,P<0.001)exertedsignificanteffectsonthemodel.Menratedbeardsmoreattractivethanwomen.Bothwomenandmenwhoaresexuallymoreinterestedinmenpreferredbeardsmorestrongly(n=374,m=0.698,SE=0.031andn=3721,m=0.595,SE=0.024,respectively)thanmenandwomennotsexuallyinterestedinmen(n=347,m=0.639,SE=0.032andn=93,m=0.446,SE=0.049,respectively).Homosexualwomenshowedtheweakestpreferenceforfacialhair,butthisgroupmadeuponly2%ofthesample.Removingthenon-significantSexxOrientationinteractionterm(F1,4425=2.68,P=0.102)didnotalterthesignificanceofthemaineffects.

FigureS2.Meanselections(±SEM)forhairyfacesamongmaleandfemaleparticipantswhoreportedsexualpreferencestomenandtowomen.

Geographicvariationinmen’sbeardednessVariationinmen’sfacialhairstyleswasquantifiedbyoneauthor(EFM),blindtothepredictionsofthecurrentstudy,whoscoredphotographsofmen’sFacebookprofilepictures(www.facebook.com).

FigureS3.Eachprofilepicturewasscoredasthemostappropriateoftenpossiblefacialhairstyles:0=clean-shaven,1=stubble,2=moustache,3=goatee(withoutmoustache),4=Goatee(withmoustache),5=Sideburns,6=Sideburnsandmoustache,7=moustacheandsoulpatch,8=Fullbeard(trimmed),9=Fullbeard(bushy)

Geographicvariationinmen’sbeardedness

Figure S4. Cross-cultural variation in men’s facial hair styles. Data are the percentage of each facial hair style recorded among men from each country.