In evolutionary psychology, symmetry especially facial symmetry is one of a number of traits, including averageness and youthfulness, associated with health, physical attractiveness and beauty of a person or animal.^[1] It is also hypothesized as a factor in both interpersonal attraction and interpersonal chemistry. Many factors support the natural favoritism towards symmetry. Men tend to start their sex life three to four years earlier than lopsided men. Female partners of symmetrical men enjoy orgasms in 75 percent of sexual encounters, as compared with 30 percent for asymmetrical men. Animal studies show that diseased mothers give birth to offspring that show greater asymmetries. From human studies, it is known that women with asymmetrical breasts are less fertile than those with greater symmetry.^[2] Evolutionary psychology (abbreviated ev-psych or EP) is a theoretical approach to psychology that attempts to explain certain mental and psychological traits—such as memory, perception, or language—as evolved adaptations, i. ... This article or section does not cite its references or sources. ... Many see natural beauty in the rose. ... In social psychology, interpersonal attraction is the attraction between people which leads to friendships and romantic relationships. ... In the fields of sociology, behavioral psychology, and evolutionary psychology, with specific reference to intimate relationships, romantic relationships, or friendships, interpersonal chemistry is a reaction between two people or the spontaneous reaction of two people to each other, especially a mutual sense of attraction or understanding. ...

Health and physical attractiveness

Edler ^[3] cited research supporting the claim that bilateral symmetry is an important indicator of freedom from disease, and worthiness for mating. Facial asymmetries and minor physical anomalies begin to appear early in embryonic development, mainly the first trimester of pregnancy, and can be a sign of instability during this growth. Fluctuating asymmetry (random differences between two sides, as opposed to the deliberate natural asymmetry in some animals) develop throughout the lifespan of the individual and is a sign of the phenotype being subjected to some levels of stress. The elaborate patterns on the wings of butterflies are one example of biological symmetry. ... It has been suggested that embryology be merged into this article or section. ... A pregnant woman, or gravida Human pregnancy refers to the process by which a human female carries a live offspring from conception until childbirth. ... Individuals in the mollusk species Donax variabilis show diverse coloration and patterning in their phenotypes. ...

The ability to cope with these pressures is partly reflected in the levels of symmetry. A higher degree of symmetry indicates a better coping system for environmental factors. While the visible signs of this may not be particularly apparent, it is thought that they have at least a subconscious effect on people's perception of their beauty. Zaidel et. al.^[4] in an empirical study upholds the claim that facial symmetry may be critical for the appearance of health. Their study disputes, however, the beauty or attractiveness claim. This article may contain original research or unverified claims. ...

Facial symmetry is neither the only trait nor is it necessarily the most important trait of what a culture considers attractive. The competing aesthetic theory of wabi sabi posits the existence of beauty through imperfection. A Japanese tea house which reflects the Wabi-Sabi aesthetic Wabi-sabi (in Kanji: 侘寂) represents a comprehensive Japanese world view or aesthetic centred on the acceptance of transience. ...

Interpersonal attraction

Suzi Malin, a British portrait painter, wrote Love at First Sight (ISBN 0-7566-0401-X) to examine the relationships of 50 celebrity couples. She speculates that there are three aspects of facial symmetry which attract one person to another: echoism, harmonism and prima copulism. Echoism is the similarity of one or more facial features, particularly the eyes, eyebrows, nose and mouth. Harmonism is a similarity in facial proportions, usually involving the features and the distance between them. Prima copulism is an attraction to another person based on them having similar features to someone with whom they formed a strong interpersonal bond with at an early age, usually a mother or father. Painting by Rembrandt self-portrait Detail from Las Meninas by Diego Velazquez, in which the painter portrayed himself at work For the computer graphics program, see Corel Painter. ... Megastar redirects here. ... A human eye. ... The eyebrow is a bony ridge above the eye that protects the eye and bears a tuft of facial hair in most mammals. ... Human nose in profile A typical bulbous human nose Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration. ... Look up Mouth in Wiktionary, the free dictionary. ...

Historical perspective

This normative study of the bone structure of the face and skull places it in the intellectual traditions of Phrenology and Craniometry. These earlier traditions ambitiously sought to assess character, personality, or intelligence from a person's bone structure. By contrast, the current study primarily focuses on aesthetic concerns that, if misapplied, would not result in infringement of a person's legal or civil rights. In philosophy, normative is usually contrasted with positive, descriptive or explanatory when describing types of theories, beliefs, or statements. ... A 19th century Phrenology chart Phrenology (from Greek: φρήν, phrēn, mind; and λόγος, logos, knowledge) is a theory which claims to be able to determine character, personality traits, and criminality on the basis of the shape of the head (reading bumps). Developed by German physician Franz Joseph Gall around 1800, and... This article does not cite its references or sources. ...

Since the 1990s, descriptive studies of human facial bone structure underlie the practice of face recognition systems using software for security applications. The reliability of these systems has been brought into question. In the humanities and social sciences, the term positive is used in a number of ways. ... A facial recognition system is a computer-driven application for automatically identifying a person from a digital image. ... Computer software (or simply software) refers to one or more computer programs and data held in the storage of a computer for some purpose. ... Physical security describes measures that prevent or deter attackers from accessing a facility, resource, or information stored on physical media. ...

References

• Edler, RJ. June 2001. "Background Considerations to Facial Aesthetics". "Sexual reproduction and parasite resistance" section retrieved 31 May 2005.
• Fink, B; Manning, JT; Neave, N; Grammer, K. "Second to fourth digit ratio and facial asymmetry". "Introduction" section retrieved 31 May 2005.

May 31 is the 151st day of the year in the Gregorian calendar (152nd in leap years), with 214 days remaining. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... May 31 is the 151st day of the year in the Gregorian calendar (152nd in leap years), with 214 days remaining. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ...

Footnotes

1. ^ Rhodes, Gillian; Zebrowitz, Leslie, A. (2002). Facial Attractiveness - Evolutionary, Cognitive, and Social Perspectives. Ablex. ISBN 1567506364. 
2. ^ Morris, Desmond (1997). The Human Sexes – A Natural History of Man and Woman. St. Martin’s Press. ISBN 0312183119. 
3. ^ Edler R. J. "Background Considerations to Facial Aesthetics", (British) Journal of Orthodontics, Vol. 28, No. 2, June 2001, pp. 159-168.
4. ^ Zaidel D. W., Aarde S. M., and Baig, K. "Appearance of symmetry, beauty, and health in human faces", Brain and Cognition 57(3):(2005) pp. 261-263.

External links

• "Appearance of symmetry, beauty, and health in human faces" -- link to article by Zaidel et. al.
• "Teeth, Beauty, Biology, and Health" – a class handout on dentition and facial symmetry at the College of Dentistry – University of Illinois at Chicago.
• FaceResearch – Online studies on facial symmetry by researchers affiliated with University of Aberdeen (Scotland) School of Psychology, and University of St. Andrews (Scotland).
• Symmeter – a proprietary web-based application that measures symmetry