Provine Robert R, Cabrera Marcello O, Nave-Blodgett Jessica
Department of Psychology, University of Maryland, Baltimore County, Baltimore, Maryland, USA.
Evol Psychol. 2013 Aug 16;11(4):873-84. doi: 10.1177/147470491301100411.
Among primates, only humans have the white sclerae that provide the ground necessary to display their own color and that of the overlying conjunctiva. Scleral color, primarily redness, provides cues of socially and biologically significant information about an individual. The present study examines the effect of the asymmetry of binocular scleral redness on perceived sadness, healthiness, and attractiveness by contrasting ratings of images of individuals who had one, both, or neither sclera reddened by digital editing. Building upon previous research, this study further defines the details of the scleral color display and contributes to the more general issue of facial and body symmetry, predictors of phenotypic condition and genotypic quality that are of interest to evolutionary theorists. Individuals with binocular and monocular redness were rated as sadder, less healthy, and less attractive than those with untinted control sclerae, with ratings corresponding to the degree of redness or whiteness. Bilaterally symmetrical (binocular) scleral redness or whiteness provided anchorage points for ratings, with ratings for bilaterally asymmetrical (monocular) redness or whiteness falling between them; there was no unique effect of asymmetry.
在灵长类动物中，只有人类拥有白色巩膜，这为展现自身颜色以及上方结膜的颜色提供了底色。巩膜颜色，主要是发红程度，能提供有关个体的社会和生物学重要信息的线索。本研究通过对比对数字编辑使其一只、两只或没有巩膜发红的个体图像的评分，来考察双眼巩膜发红不对称对感知到的悲伤程度、健康状况和吸引力的影响。基于先前的研究，本研究进一步明确了巩膜颜色显示的细节，并为面部和身体对称性这一更普遍的问题做出了贡献，面部和身体对称性是进化理论家感兴趣的表型状况和基因型质量的预测指标。与巩膜未染色的对照组相比，双眼和单眼发红的个体被评为更悲伤、更不健康且更缺乏吸引力，评分与发红或发白程度相对应。双侧对称（双眼）的巩膜发红或发白为评分提供了参照点，双侧不对称（单眼）发红或发白的评分介于两者之间；不对称并没有独特的影响。
