How do humans and animals select their mates?
This question already spiked Charles Darwin’s curiosity 140 years ago. Darwin claimed that sexual selection is based on the individual’s ability to find a fitting mate and create offspring. Sexual selection focuses on traits that help an individual find or win over mates for breeding, and to select mates with traits that raise the offspring’s ability to survive and multiply (Darwin, 1859). Sexual selection acts in two ways: The first is a competition between males for the access and right to mate with females, and the second is the female’s selection of the most fitting male, with whom she can breed offspring with high survival rates.
How does the selection of a mate work?
The evolution process has lead to the development of protection mechanisms in animals, making them stronger, having larger bodies, more color and beauty, a fact that helps a male win physical competitions against other males, and impress the females. Stags with large antlers, for example, who win fights, raise their chance to overpower other males, and raise the chance that females will select them for breeding since they have higher-quality genetics. Just as attraction serves mate selection, rejection serves for self-preservation and avoidance of pollution and harm (Tybur, 2009). In humans, unique faces reflect the traits that cause sexual attraction.
Facial Structure has a Central Role
Facial structure plays an important roll in selecting a partner (Thornhill R. G S, 1999). Each individual has a personal identity, which is expressed in his or her facial structure. Individual DNA sets and influences facial structure and set the individual apart from others. (Peter Claes 2014) (Liu F 2012). This individuality enables personal recognition, which reflects the importance in social interactions (Michael J. Sheehan, 2014). The face is among the most important visual stimuli, which enable recognizing a person, their mood, their gender, their age (Moalem S, 2014). There is research that supports the assumption that humans have cognitive neural mechanisms dedicated to recognizing faces (Kanwisher N 1997). The ability to extract information from a face is important for social interactions and enables communication and expression of verbal and non-verbal messages (Pascalis O 2009). The face exposes the developmental and genetic history of an individual and tells of their familial relationships, health, parental adaption, and more (Moalem, S 2014) (G 2006) (Barber N 1995). Facial attractiveness is deeply coded in the individual’s biology (Chatterjee AT 2009). Thus, men and women both pay great attention to their physical appearance. (Buss DM 1986).
The signals reflected in our face would not be useful would they not affect the cognition and emotional responses of the opposite sex. These decisions necessarily involve emotional and cognitive assessment of potential partners. Physical attraction stems from an interaction between the brain and the face, and the way in which they are conceived by the individual’s brain (Johnston VS, Facial Beauty and mate choice decisions 2008), and thus judging an attractive physical appearance is individual. (Honekopp 2006).
The face reflects means by which an individual selects the optimal partner.
What makes a beautiful face?
Beautiful faces reflect an exact mathematical index.
The golden ratio is a mathematical equation discovered by Leonardo Fibonacci (1170-1250). It was discovered that various geometrical structures were shown to adhere to this ratio in terms of their size or angles, including even molecular and microbiological structures and astronomical and galactic structures. There is also a correlation between faces that are close to the proportions of the golden ration, and their perceived beauty. That is to say, beauty is measured by an exact mathematical index. Therefore beauty depends not only on the era, culture or faith. The golden ration also explains the fact that we all consider the same faces as beautiful (Jefferson, 2004).
What makes an attractive face?
In contrary to the “Golden Ratio,” which measures objective beauty in an exact mathematical index, attractiveness is a subjective perception of physical appearance. Difference people have different preferences. People examine attractiveness based on their own level of attractiveness (Anthony C. Little 2011), their hormone levels (Welling 2008), the genetic and health quality that is reflected in the face (Barber N 1995), and more. Each individual has a unique biological status, and so each person has a perception of attractiveness that matches his or her biology (Anthony C. Little, 2011).
Differences between men and women- the parameters that attract a man to a woman are different from those that attract a woman to a man (Buss D M 1986). There are gender differences in the morphology due to evolutionary sexual selection, in order to attract partners. (Barber N 1995)/ Women compete against one another for high quality partners, by showcasing their breeding abilities, like distribution of body fat, small nose, and more. Men will increase their virility through their power and dominance, which are expressed in their physical appearance. Visual cues reflect hormonal status, genetic quality and health, which are unique to each individual. (Barber N 1995).
Subjective Matching- Certain genetic pairings might cause the birth of an offspring with defects. Many studies have examined the connection between marriage of relatives and birth defects. All the studies found high incidence of birth defects in children whose parents were first cousins, compared to children whose parents were not related (Bittles and ML Black 2010). Therefore matching is individual and personal.
Mutli-directional matching (the man matches the woman and the woman matches the man) - In order for there to be an optimal biological match between partners, the match must be multi-directional. The pairing is made up of two unique subjects that must match one another biologically, which can be seen and examined in facial structure.
The unavoidable evolutionary process causes people to search the optimal mate for breeding and survival. Nature has created an added significance for humans, which reflects personal biology and tells of personal traits and qualities. Attractiveness stems from an interaction between the brain and the face, and is individual and subjective.
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