The Female Body Deconstructed

Unlike men’s bodies, the bodies of women are the subjects of great debate and controversy. A woman’s body is viewed as something which not only belongs to a woman but also belongs to her family, her partner, her community and her culture. The social, cultural and biological ideologies surrounding women’s bodies greatly impact the way that women view themselves, their interactions with those around them, and they way they are viewed by their society. While these ideologies may affect women on a cultural and psychological level, they are often based on biological facts which result from human evolution. In this post, we will discuss the impact of women’s subtle ovulation and myths surrounding menstruation on the views about women in different cultures.

Concealed Ovulation

Humans are said to be the only mammals whose ovulation is understated and subtle. Baboons for instance, have reddened butts and this enables male baboons to know when exactly the female baboon is ovulating and therefore not waste valuable genetic resources. Humans however, are differentiated from all other mammals as women’s ovulation is very subtle and most miss it on a conscious level. However, there are multiple new studies in evolutionary psychology that explain that while we may not recognize ovulation consciously, we respond to the peak in our fertility through subtle changes in action.
For instance, when single men interact with a woman who is at the peak of her fertility in the menstrual cycle, they rate her as being more attractive than at other points of time in the cycle. Men in committed relationships however, rate women as being less attractive as they subconsciously understand the threat that these fertile women pose to their relationships. This seems to in itself make a case for fidelity as being favorable for natural selection. Scientists posit that fidelity is favorable for passing on genes and therefore it is more in the interest of the individual to preserve their relationship rather than jeopardize it by possibly cheating on their partner. In essence therefore, the committed men attempt to ward off their attraction to attractive fertile women by subconsciously rating them as not attractive in the hope that it doesn’t actually become a threat to their relationships.
There are also subtle changes in behaviour and physical appearance when a woman is at her fertile best. For instance, the pitch of a woman’s voice is higher and men find their body odor more attractive. Women in relationships with sexually less attractive begin to find other men more attractive when they are ovulating and they tend to dress more attractively and attend more parties and clubs.
The studies on ovulation support fidelity and good genes over evolutionary urges to spread one’s genes and this seems to bode well for human monogamy. While urges to cheat always exist, biologically we are tuned to understand that monogamy and superior mate selection are of more importance. 

Evolution of Concealed Ovulation

As previously mentioned, human females, unlike other mammals, lack a sharp peak of interest in sexual activity at or close to ovulation(estrus). This basically means that human females do not become more or less sexually active during times when they are physically fertile, nor do they give off any sign to males or themselves that they are in such a state. Many scholars have questioned this lack of estrus in the human population and theories have been heavily debated. 

 
There have been many theories presented as to why this phenomenon is apparent in humans, most relating to the male to male interactions within society.  Some theories put forth that it is important for men to work together in community, rather than competing for the attention of females, and therefore the lack of estrus is due to the fact that without it, males are encouraged to bond.  This idea of pair bonding among males puts forth that due to the extended receptivity of females with continued sexual relations with the same males, as both sexes do not know when ovulation will occur, stands to individualize sexual relations among humans.
Nancy Burley, however, argues in her article “The Evolution of Concealed Ovulation” that these arguments fail to compensate for “continuous receptivity, the concealment of ovulation from conspecifics, and the concealment of ovulation form females themselves.” What is most interesting within Burley’s argument is the idea of ovulation being hidden from females themselves  Burley maintains that this concealment from females themselves is part of the process of natural selection, which obscured ovulation to counter human tendencies among females to avoid conception through abstinence from intercourse near ovulation. This theory then goes on to explain that human females are hesitant to have children due to the hard burden, economically, physically, and socially, that they would have to bear and therefore might be prone to avoid sexual encounters during ovulation.  This, in order to be prevented then, would be combated by natural selection by a lack of estrus. While this theory is certainly fascinating, it has been disputed by many scholars who find the reasoning unjust. It certainly would go against many existing points in evolutionary theory which suggest females have fewer sexual encounters with males to ensure reproduction and stability thereafter, while males have more sexual encounters in order to spread their seed. 

Menstrual Taboos

Menstruation in women the world over has come with many different forms of what the article, “A Woman’s Curse?” by Meredith F. Small calls “menstrual taboos”. Often these taboos take the form of forcing women to separate themselves from the rest of the society, or to wear certain symbols that show they are menstruating. The article says that in some cultures, menstruating women are forbidden, “to touch certain items used by men, such as hunting gear or weapons…” (1). These taboos have often thought to have been brought about by culture and society. Some anthropologists, the article says, have even argued that these taboos “serve to prevent menstrual odor from interfering with hunting…” (1). However, this article argues that maybe menstrual taboos are a form of evolutionary advantage.
           The website called “A Darwin Study Group” has a section titled, “Seminar Two: Evolution of Sexuality, Menstrual Taboos”. This article discusses similar points as described above but it mentions the fact that these evolutionary advantages to the taboos may be found in the fact that identifying women’s menstrual taboos (however a given society decides to do so) is beneficial for the society as a whole because it allows the males in the society to identify which women are healthy and fertile. For example, a woman being separated from her society to live in a hut outside their grounds gives males the opportunity to document how regular/irregular this women’s menstrual cycle is. This gives males the chance to choose an appropriate mate, one who is healthy sexually and can reproduce. Knowing this, gives males and females both an evolutionary advantage, allowing healthy individuals to find each other faster and mate, reproducing more.
           While this website also argues that part of the way that these taboos are formed has to do with culture, the fact that societies all over the world are interested in creating some form of taboo is evolutionarily biological. “There are clearly variations on this theme across human cultures. Human behavior is flexible, shaped by culture and upbringing as well as by genes.” So while in one culture the taboo may be to banish the menstruating woman to the outskirts of their societal grounds in another it could be celebrating the menstrual cycle of women. But the fact still remains, that cultures all over the world have certain menstrual taboos and the necessity for them is evolutionarily successful.

Conclusion:

"If natural selection is the cake that makes biology understandable, sexual selection is the icing."
              -Dr. Dimijian 

“Since 1989, Greg Dimijian has taught a three-part seminar in behavioral ecology to the fourth-year psychiatry residents at the University of Texas-Southwestern Medical School in Dallas, where he is a Clinical Associate Professor of Psychiatry.” He noted that Darwin believed that sexual selection is fundamentally different from natural selection. “He [Darwin] viewed it as a separate and powerful explanatory principle in biology”(Dimijian). One example of this disconnect is apparent in peacocks in which the male is in a lose-lose situation. The female peacock is attracted to the male while longer, brighter, more colorful feathers, thus inducing sexual selection: however, these long, bright and colorful male birds are not only appetizing to females, they also become the prime target of predators. These opposing ideas have been stumping scholars since Darwin.
Studies have shown that modern culture has caused woman’s menstruation cycles to be significantly different from that of a “natural fertility”(Small 1) culture free from birth control and norms for small families. The modern woman has significantly more menstruation cycles than the “natural fertility” woman: 400:110. The difference between the two numbers of 290 days is the time that is spent pregnant or lactating. This increased number of periods lowers a woman’s biological resources and has a “hundredfold” increased risk of getting breast cancer. (Small 4)
These conflicting of ideals for women of, being attracted to a male who has greater chance of being eaten or living in an industrialized society with options and getting breast cancer, are making it harder for science to provide answers for our hunger for knowledge about human sexuality.

Sources:

Tierney, John. "Findings — The Threatening Scent of Fertile Women - NYTimes.com." The New York Times - Breaking News, World News & Multimedia. 21 Feb. 2011. Web. 03 May 2011. <http://www.nytimes.com/2011/02/22/science/22tier.html?_r=1>.

http://adarwinstudygroup.org/sexuality/menstrual-taboos/
 

Burley, Nancy. "The Evolution of Concealed Ovulation." The American Naturalist 114.6 (1979): 835. Print.

Evolution of Sexual Violence

INTRODUCTION

Genetically and biologically male and female were once very similar, but something has happened over the course of time that has caused the differences we know and recognize today. This asymmetry of our co-evolution can be seen in humans across genders and cultures. The cause of these differences has been argued by attributing them to either nature or nature. Sexual violence is one example of “a reflection of an asymmetry in the way the sexes treat each other.”

There is a long history of sexual violence towards women by men. This is most greatly seen in times of war, but can also happen in married relationships.  Scientists are trying to scientifically justify the reasons for rape while some scholars persist that, “there must be an underlying evolutionary thread that reflects a fundamental difference in gender identity and sexual strategy, encoded in behavioral predispositions.”

Scientific Justification for Rape

       Biologist Randi Thornhill and cultural anthropologist Craig T. Palmer argue in their book A Natural History of Rape that “rape is a complex crime with strong roots in human evolution” (Scientific Study). While most feminists, sociologists, law enforcement officers and rape survivor advocates content that rape is about male domination rather than sexual arousal, Thornhill and Palmer suggest that rape is a reproductive strategy learned during men’s evolutionary history. This is why, despite legal and social sanctions against rape, rape continues to be a societal issue.

        They suggest two potential causes for the rape proneness of men. One hypothesis is the “indirect selection for rape” during human evolution meaning that rape is a byproduct of the differences in women’s and men’s sexualities (Thornhill).  Some of these differences include men’s greater visual sexual arousal, autonomous sex drive, desire for sexual variety, willingness to engage in impersonal sex, and reduced ability to abstain from sexual activity. These behaviors were favored in human evolution because they allowed men to access different sexual partners and increase their potential for having viable offspring. This evolutionary history has created a strong libido in men and “when it is combined with evolved female mate choice, rape arises as an incidental effect” (Thornhill). Thornhill and Palmer also hypothesize that rape itself is an adaptation. According to their research, a rape proneness is present in all men but only expresses itself when conditions suggest it would be beneficial. All men understand that rape is a reproductive strategy that they can use but Thornhill and Palmer caution that men are not “genetically predisposed to rape” or that a rape gene exists (Scientific Study).

        In order to prevent men for utilizing rape as reproductive strategy, Thornhill and Palmer suggest that we improve the conditions in which young people, especially young men, learn about sexuality and development. They believe that evolutionary informed sex education courses rather than rape prevention strategies would allow young people to learn about differences in sexuality for men and women. For example, when young women say no they are actually expressing disinterest that will never shift into interest. These courses could also provide young men with information that will help them avoid situations in which they may rape and help them distinguished perceived sexual signals from sexual rejections.

Sexual Violence in Marriage

      Sexual violence, according to the article “An Evolutionary Psychological Perspective on Male Sexual Proprietariness and Violence Against Wives” by Margo Wilson and Martin Daly, can be found in marriages around the world. This kind of violence is physical violence done to the wife in the marriage by the husband. The article cited evidence from all over the world of husbands physically abusing their wives. They claim that this kind of violence, among other things, reflects evolution (110). Citing Darwin’s theory on survival of the fittest, Wilson and Daly claim that “sexual proprietariness is a psychological adaptation of the human male,” (114).  
      “Proprietariness”, according to these authors, means basically that men are inclined to claim women as their property, “as songbirds lay claim to territories, as lions lay claim to a kill,” (114). This also involves a sense of entitlement where the male feels hostility and grievance for any “trespasses” against his territory. In this way, for example, a male would feel hostile towards rivals (for his love with “his” female) while also feeling grievance for his woman having cheated on him in any way. This grievance would allow him, in a community, to gain support from onlookers in the way of justification or punishing those involved in the so-called wrongdoing. The “injured” or cheated-on male would then be allowed, rightly in the eyes of the community, to take out his aggression on not only the other male but also his wife.
        The article claims that this kind of violent behavior came from a time when there were limited resources, i.e. limited females. Because of this, males were automatically placed “in an arena of actual or potential conflicts of interest,” (115). In order to reproduce and pass on their genes, they had to be very territorial over their females. Those males who did not pose a threat to their rivals or to their females often did not reproduce. The article claims that violence against the wife reduces “her likelihood of imminent departure” because she is afraid of the repercussions (120). This then allows the husband to have complete control of the reproduction of the wife and therefore increase his chances at reproduction. Violence against the rivals keeps the rivals from mating with the wife and thereby increasing the husband’s chances for mating with her. The article goes into depth about what exactly this kind of relationship brings about in both males and females and just how much community has an effect on this, but it is very explicit in saying that evolution is one of the key driving factors behind sexual abuse in the marriage.

See the video below for more information:

  

While this video takes a different route in the end of it’s presentation than does this post, the first half is still very interesting and educational for the purposes of this blog. 

Rape/Sexual Assault During Times of War 

During times of war the codes of conduct that are socially acceptable in society are often neglected and traded in for those that will maintain survival.  In the article The Evolution of War and its Cognitive Foundations by John Tooby and Leda Cosmides, the evolution of war is analyzed.  While a fight is a violent conflict between two individuals, a war is a violent conflict between two coalitions of individuals that can only function with the cooperation of many people.  When taking this into consideration, it is then important to note that the action of War is something that is only perceived among the human species, and therefore is a subject of fascination for evolutionary scientists as they often look for a means of explaining it’s roots. This is due to the fact that war has been associated with the evolution and history of the human species as well as the masculanization of males in society. Those who fight the war, however, while important are often not the most affected by this neglect of social norms, but rather it is the people left behind that are terrorized and impacted.  When considering rape and sexual assault during times of war, such violence, which is normally purposefully hidden from the obvious eyes of society but never-the-less present, is visible in its raw, brutal form.

In Maria B. Ojulic’s article Embodiment of Terror: Gendered Violence in Peacetime and Wartime in Croatia and Bosnia-Herzegovina, the topic of rape during the time of war is analyzed as reflecting the gendered violence of peaceful times. The political background of the situation in which the war took place was such: Croatia, Slovenia, and Bosnia-Herzegovina (all republics of socialist Yugoslavia) declared their independence, leading to the wars between the different areas to maintain control. During the war, as well as after the areas were under Serbian occupation, and it was at these times that such violence occurred. Contrary to popular belief, the presence of gendered violence is not something that merely appears during times of war but rather something that is formed by drawing on the meaning of sexuality created during peacetime.. As Ojulic stated, “To understand the public violence in former Yugoslavia requires insight not only of a wartime ‘culture of violence,’ but also o the ‘culture of peacetime.The two are inextricably interlinked.” In the society, the woman represented marriage, family, and village and thus held both the family’s honor and it’s shame. When the rape’s took place during war it signified humility throughout the society. The rapist were able to situate physical and moral control over the women  and dishonor their male family members for being unable to protect them.  Ojulic also comments on how rape and “play rape” have been a historical part of marriage and courtship in southeastern Europe. Then, with the beginning of the war, jokes and songs were formed within the population showing the tension placed on sexual violence that was to come. 

View the Video below to further information on these victims

 

The evolution of rape during the time of war seems to have gone through different stages to its creation. First, rape was used as a reward to the conquerors of a war in ancient times. This is contested in many forms, including the Old Testament and Roman scriptures, which both describe women being raped from conquered tribes/armies by the victors habitually. In this same context, foreign women were kidnapped and raped as spoils of war and then forced to marry their captors.  In more recent times, including wars such as the War of Bosnia and Herzegovina (previously mentioned), wars in Peru, and the Genocide Wars in Rwanda, rape has been used to show dominance over the conquered/targeted group.  Rape, in this sense, is also used to breed out these groups as well. But the last stage, which has seemed to gain popularity among warring countries within the last few decades utilizes rape as a systematic, structured weapon of war in order to intentionally inflict terror.

In a website focused (noted in sources) on the rape of African women during the genocides within the last decades states, "Rape was a weapon of terror as the German Hun marched through Belgium in World War I. It was a weapon of revenge as the Russian Army marched to Berlin in World War II, it was used when the Japanese raped Chinese women in the city of Nanking, when the Pakistani Army battled Bangladesh, and when the American G.I.s made rape in Vietnam a 'standard operating procedure aimed at terrorizing the population into submission'." In this way rape was used as a means to force a society into submission as well as terrorize the people, as women are seen as the faction of life and honor. By systematizing the rape of the part of human society that can create the future generations (and in a sense possibly impregnating them) these conquering armies are able to cause shame on these women while keeping the populations in a constant state of terror. In this same way, conquered or imprisoned sections of society are often raped as a form of punishment and shame during times of war as well, whether they are men or women as the same intent is achieved. 
Click the link below to further information of rape as a weapon of war: 
http://www.cbsnews.com/video/watch/?id=4356720n&tag=related;photovideo 

Sexual Assault as Evolution

Sexual assault or coercion is explained by multiple theories, evolution being one of them. The evolutionary theory explains how sexual assault may be explained by natural selection. According to natural selection, men invest less energy in sexual reproduction and therefore tend to have/want multiple partners so as to increase their chances of adaptive success. Women on the other hand, require time and energy for the reproductive process and therefore are selectively given the right to choose their partners. Men with more partners are also considered more successful and therefore the woman’s right to choose yet again goes against a man’s evolutionary advantage. Rape in essence takes a woman’s right to choose her partner away from her in favor of the man’s reproductive success. This may have come by because it becomes harder for men to be reproductively successful and therefore they must take the choice away from women. Women on the other hand, are adapted to resist sexual advances from males they do not view as reproductively favorable. Therefore rape is a adaptively a drawback for women as it does not allow them to ensure paternity certainty or fitness in their mates and decreases their reproductive success and therefore their ability to pass on their genetic code. The evolutionary gap between a man’s need to have multiple partners and a woman’s need to choose their partners is the vacuum which rape evolutionarily fills in.
        However, this evolutionary justification of rape or the rape adaptation hypothesis as posited by Thornhill and Palmer almost seems to justify the ‘boys will be boys’ reasoning and many theorists criticize it. Other offender related theories imply physiological and neurological aspects such as hormones and trauma that often leads to an increase in violent behavior and assault. Alcohol is also an important factor as alcohol tends to influence perception of sexual behavior. Certain psychopathological traits like aggression are more highly linked to rape but they are not mutually exclusive and there are many other environmental, genetic, social and personality traits that may be influence the behavior of a potential rapist. Socially, the history of rape affects the chances of further behavior as violence within the family structure, the media’s portrayal of sexual relations and sexuality, culturally acceptable sexual mores and notions of what a relationship should be influence how a society views rape. Marital rape for instance in considered the norm in societies where women are perceived as being the property of their husbands or dependent on their husbands even. In conclusion, rape and other sexually violent behavior is attributed to evolution, individual characteristics or socio-cultural mores. There are multiple causes for it but at the end of the day, what must be taken away from any analysis of rape is that rape only serves to further divide the society and is something that both men and women must come together to fight.
 

 

Non-Reproductive Sex vs. Evolutionary Theory

Introduction 

When studying human sexuality, one cannot deny the overwhelming presence of non-reproductive sex. Non-reproductive sex makes up for most of human sexual activity and it has been an integral part of the evolution of human sexuality. While it does not directly provide us with reproductive benefits as it is not reproductive in nature, it must confer some reproductive advantages for it to have survived the evolutionary weeding out of unnecessary traits.

           Non-reproductive sex plays a role in sexual selection for instance. Sexual selection is one of the two selective forces in evolution - natural selection and sexual selection. Sexual selection is the selection of a mate by the female and the female is given the right to choose and therefore the power. However, once she has chosen a mate, it is necessary for her to keep the man with her as raising a human child is a time consuming process and the gestational period is particularly taxing for the woman. Non-reproductive sex during the gestational period therefore may be a way for the woman to keep her husband at home with her while she invests the tie and energy required to give birth to offspring. Non-reproductive sex in essence could therefore be a way for the woman to ensure monogamous relationships and fidelity.
           Non-reproductive sex is also a necessary by-product of the way ovulation has evolved in women. Humans are one of the only mammals where it is inherently difficult to say when one is ovulating. Since it is difficult to know when the possibility of fertilisation is at its highest, non-reproductive sex maximises the chances of fertilisation taking place almost by a trial and error method. Non-reproductive sex ups the ante, raises the likelihood of of one of those sexual interactions leading to fertilisation.
           Non-reproductive sex also has some indirect benefits for women. The hormones that regulate sexual activity in women, such as estrogen and progesterone can have benefits to women beyond the regulation of reproductive functions. While estrogen plays a role in puberty and pregnancy, it also promotes blood clotting and prevents the loss of calcium from bones. Non-reproductive sex keeps these hormones regularly active in the woman’s physiology and they can therefore keep regulating these other spheres as well.
           Non-reproductive sex, as has been demonstrated does have its strengths, reproductive or not. However, some spheres of it have no obvious connection with reproductive advantages and it is therefore interesting to see why these are still a part and parcel of human sexuality. Birth control for instance seems counter-intuitive to evolution and homosexuality so far is not reproductively viable. However, they both seem to continue to survive evolutionary forces and therefore they are worth studying. 

Birth Control

Natural selection has been defined as nature’s favoring certain characteristics that enhance fitness, otherwise known as the ability to produce viable offspring. So what happens when humans are trying to prevent pregnancy and meddling with this “natural selection”? Some people see birth control as beneficial while others see it as harmful or immoral.

The pill was originally thought to remove the label that women were only allowed in the home with the children, permitting them to separate from the family and enter the work force.  But in modern day, for women, the pill spells freedom from fear: fear from having a child that could potentially interrupt all plans for a career.  

Watch the video below to view a CBS cover on Birth Control:
http://www.cbsnews.com/video/watch/?id=6466017n

             However, some also argue that birth control is the reason for the high divorce rate.

It has been proven that women who are ovulating tend to be attracted to a man with more masculine facial features and traits of dominance and competitiveness.  Because birth control eliminates ovulation completely, the time when the female naturally selects a partner based on masculine traits and genetic diversity is eliminated too. This is effecting natural selection because women are all of a sudden attracted to men they would ordinarily not glance at. The result of this is that when the woman gets off the pill to start a family, their taste in men changes, and divorce rates rise.  

Women also tend to prefer a man who is genetically different as discussed in mate selection. Because birth control affects woman’s natural instinct to select a male of low genetic similarity mutations are more common. The preference for genetically "opposite" characteristics is thought to promote bio-diversity, promoting a more varied immune system and a stronger gene pool.

Scholars will argue that because female humans and bonobos are interested in sex even at times when they’re not fertile, while females of other species are only interested in intercourse when they can get pregnant, most likely indicates that sex has another purpose or benefit that allows it to be selected for reproduction for select primates.  Birth control allows for recreational sex with may create/reinforce the close social bonds made with a male. This close and intimate relationship can make it easier to successfully raise children while reducing the risk of divorce. By going on the pill and lowering the number of fertility-induced matings, the birth rate may lower. This would be a positive for humans if it established a concern for quality over quantity and investing more into a few. This could be reinforced due to the ever-growing population, a depleting amount of food, and the amount of time and energy it takes to raise and teach a child.
           Birth control can be seen as positive or negative depending on how one looks at it. But, in my opinion, one thing it does do is gives the women the ability to be independent and make their own choices when it comes to their bodies.

Homosexuality

The question of homosexuality and whether or not it is natural falls in direct line with the concept of evolution. It is often asked: If homosexuality is natural how did it get selected by evolution? One article, “Twin and Sibship Study of Overt Male Homosexuality,” states that “no gene can be assumed to be capable of determining the final choice of a sex partner.” If this is true and there is no gene that determines a person’s sexual orientation then sexual selection is not genetic and therefore not affected by evolution. People who argue that there is no gene that affects sexual selection often feel (according to the article, “Homosexuality: A Paradox of Evolution” by Preston Hunter) that if there were a specific gene for homosexuality then evolution would have weeded it out—in other words, homosexual people would not have reproduced and therefore their genes would have been lost.

           However, Hunter also states that studies over twins’ sexual preference have shown, “A strong positive correlation between relatedness and similarity of sexual preference…" Identical twins raised apart, for instance, are more likely to both be homosexual as adults (if one is homosexual) than fraternal twins, and both are more likely to share sexual orientation than genetically unrelated siblings raised together. Some twin studies have shown concordance rates as high as 100% (Friedman, 1988, p. 27). Based only on the data from these studies genetics can account for 31 to 74 percent of sexual orientation (GregBear, 1993; UPI no author, 1993; CNN Health Works, 1993; Bower, 1992; Puterbaugh, 1990).”

In this way, there might be some sort of genetic material that passes to offspring through reproduction (i.e. evolution) which accounts for sexual selection. Hunter also argues that simply because one is homosexual doesn’t keep them from reproducing—“It is not uncommon for gay men and lesbian women to marry into a heterosexual relationship and sire children.” However, this would mean that homosexual preferences would have to be coupled with heterosexual preferences because otherwise that homosexual person would not be inclined to have sex and reproduce heterosexually.

Watch the video below on the Evolution of Homosexuality:

Prostitution

        The theories of evolution concerning mate selection, specifically analyzing sex, choose to explain the process with distinct focus on human reproduction.  Women choose men because of the effect it can have on their reproduction (stability, wealth, attractiveness, fitness), and men likewise choose women based on their physical features (features that will in turn be passed onto offspring).  This same theory rationals that the reason men have sex with many women is to increase the possibility of “spreading their seed,” whereas women are less likely to often have sex due to the long gestation period before birth. It states that "male desire for short-term sex is stronger than that of female...because males can reproduce more if they have sex with a greater number of women...therefore males must work hard and take risks to get sex and so have a higher sex drive" whereas women "can only have one child per year and therefore desire sex less." This furthers the preconceived misconception of a once largely male dominated scholarly world that women want sex less than men. If this were true, then how are their sex workers in modern society? Not sex workers that were trafficked, but those that willingly choose to enter the trade. Though this theory may seem illogical to many people today, it is a theory that has been believed for decades.  What is not explained by this theory, however, is non-reproductive sex, specifically prostitution.  Before the creation of birth control it was understood, by the evolutionary viewpoint, that sex was only undertaken as a means of reproduction.  Prostitution (notoriously referred to as “the oldest profession”) does not fit into any category and is kept hidden from such theories.  If it were taken into account, many evolutionary theorists would find themselves at a loss for an explanation.  
          Prostitution, which involves the selling of sex, is a form of non-reproductive sex that is far from being concerned with the reproduction of children.  To have a child in such a trade would actually be a hazard because it would possibly leave the sex worker unable to continue her line of work.  It is for this reason that prostitutes often use condoms in their line of work; this is also to prevent the spread of sexually transmitted diseases, for if they were to contract one it would also render their work difficult. Not all prostitutes are able to afford condoms and many are prevented from using them by unwilling and violent customers, even in some of the most notorious red-light districts.  

Watch the Video Below to hear the discussion on prostitution:
 
         
 

        After viewing this video, one can see that the access to condoms, and therefore safety from disease and child conception, is limited for many sex workers, and yet they still practice their trade. It is for this confusion that many scholars find themselves unable to interpret motivation behind prostitution other than a financial explanation.
        While many scholars would attempt to separate prostitution from the theory because it is a means of income and therefore financially motivated for some individuals, it is still a form of sex that cannot be explained by evolutionary theory. The misconstrued notion that prostitution is always forced onto young women might be the reasoning that some of these scholars think this way.  But the evolution of prostitution has in fact shown that while a degree of women have been forced or tricked into sex work, a good deal of women choose this line of work because of its simplicity in a high demand market and therefore have different motives in mind. 
 
Conclusion 

Throughout the years many scholars argued that human sexuality developed in the way it has in order to efficiently select mates who could produce strong and healthy offspring. As the above analysis indicates, not every sexual interaction between humans results in offspring nor occurs with the intention of creating offspring. In fact, many sexual interactions occur between partners with full knowledge that they are physically incapable of producing a child. Non-reproductive sex is not new to human history. There is also evidence of birth control and abortion methods in both ancient and modern human societies, indicating that humans have long indulged in “recreational sex”.

How does this history of non-reproductive sex shape our view of humans and human evolution?

How does this choice to engage in non-reproductive sex alter our evolutionary destiny?

What determines our sexual practices as humans, culture or biology?

Sources:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1716443/pdf/ajhg00421-0084.pdf
http://www.adherents.com/misc/paradoxEvolution.html

http://www.viewzone.com/estrogen.html

http://impossibletospell.com/2010/07/171/ 

 

The Adaptive Value of Love: Evolutionary Mechanisms Underlying Mate Selection

Introduction

In the mating game, men and women have a variety of conscious and unconscious strategies that they utilize to secure partners. These strategies were developed over millions of years of evolution, and we’re still programmed to use them today. This programing has developed in every living thing that reproduces sexually. The comparisons between species are an aspect that is vital to fully understand mate selection. One of these differences is the influence of the modern world on humans having sex.

Although science is far from having all the answers to why we behave in the ways we do, people have discovered some possible explanations.

The Mechanics of Human vs Animal Mate Selection

Sexual selection, according to Arianne Albert and Dolph Schluter in their article, “Selection and the origin of species”, is when a member of one sex mates with a member of the other sex due to various reasons. With reference to humans it is the form of natural selection that favors characteristics that assist in either attracting the selecting sex or help one in competing with others f the same sex. We attempt to clarify what some of the general factors underlying animal and in specific human mate selection are.

    Albert and Schluter both argue that the outcome of sexual selection can be seen in the behavioral displays as well as the genital shapes and sounds that “characterize male courtship and mating behavior.” Male peacocks must impress the peahens with impressive feather displays and the peahen is given the ultimate choice. Human selection is similar to mating behaviour amongst other animals in this respect because the onus of impressing the prospective mate falls on the man. Mammal females tend to be more selective of their mates as, in accordance with the differential parental investment theory, the woman has an initially higher investment in the offspring and therefore has more to lose from a genetically poor mate. Males can fertile at minimal cost as their direct input requires no more then their genes. Women however, invest the gestation period as well as the postnatal care and therefore they have to ensure that this investment has not been in vain. Women therefore tend to demand evidence of superior genetic capability before choosing to mate while men are relatively non-selective about their choice of mate. 

Click on the link below to further this information with a video:

http://videos.howstuffworks.com/animal-planet/28898-ms-adventure-primping-peacocks-video.htm

Hanna Kokko, Robert Brooks, Michael D. Jennions, and Josephine Morley, in their article, “The evolution of mate choice and mating biases” argue that there are two types of selection: direct and indirect. Direct selection (the one related more closely to successful evolutionary practices) is when the sexual selection is made to increase fitness. “A female’s mating biases are favored by direct selection if they increase he own lifetime reproductive output. Direct selection favors mating biases toward males that are more fertile, provide superior resources, offer more parental care or otherwise reduce the female’s current reproductive costs,” (3). Thus sexual selection in the direct sense is based on increased fitness overall.

Due to the structure of human society and the emphasis on monogamy, it is assumed that the man will directly contribute genes and indirectly contribute resources, financially and temporally, that will be needed to meet the needs of the offspring. Human mate selection  therefore follows along similar lines where a man’s genetic potential is valued by his physical attractiveness while his fitness potential is valued by his social standing, dominance within the social hierarchy or ambition.

Indirect selection however, is the selection of a mate based on characteristics that could possibly endanger the viability of the species. In the case of peacocks for instance, peahens tend to mate with the more attractive of the peacocks but the excess plumage however, makes these peacocks more vulnerable to predators. Indirect selection is therefore more about preference than about fitness, an aspect of evolutionary mate selection that is playing into evolutionary discourse today.

Kokko’s article says that “fitter males and the females who preferentially mate with them, will have offspring that inherit the genes for both fitness and the mating preference,” (3).Thus, the genes for both indirect and direct selection are passed to the offspring. Direct selection seems self-explanatory in terms of evolution: the fact that the female would choose a male who would increase overall fitness would fall right in line with natural selection and therefore evolution. However, indirect selection is a little more questionable. How do females evolve to choose males indirectly? How does natural selection allow for females to choose traits that might not be beneficial for survival?

One theory, Kokko’s article argues, is that a process called sensory drive pushes females to choose males indirectly (4). “It may provide the initial ‘nudge’ often required to initiate choice-display coevolution. If males are not advertising, females are unable to choose…” (4). Thus in order for reproduction to work, males must advertise their features and these features are picked up by the females whose sensory drive processes choose which males to mate with. this argument is gaining more relevance today with the debate on the impact of birth control and its impact on evolution and natural selection. 
Watch the Video below to further your understanding.

 

Mate Selection for Females and Males

         According to many scholars, male and female mate selection is concerned with exploiting the “reproductive potential and reproductive investment of members of the opposite sex” (Geary, 29). 

         Reproductive potential is the “individuals’ ability to invest in the growth, development, and later social and reproductive competencies and/or the potential genetic benefit a make would confer on offspring” and “reproductive investment is the expenditure of this potential on offspring” (Geary, 29).

        In addition to biological factors, mate selection is restricted by kin, the marriage system, societal expectations, and ecological conditions. These factors impact human females and males in different ways and, therefore, impact their mating preferences in unique, sex-specific ways. Women’s mate selection strategy is to select a mate who will conceive, raise and provide for a child with them. This strategy causes the cost of reproduction to be higher for women than for men and weight costs versus benefits when selecting potential long-term and short-term partners. In contrast, human males, like other males, compete for “access to preferred and oftentimes, multiple mates” in order to produce as many offspring as possible (Geary, 29). With this objective, males seek out more short-term relationships and are more hesitant about entering into long-term relationships and thus the are more careful when selecting  long-term partners. Although these biological drives greatly influence our mate selection they do not completely determine who are partners will be. Culture, societal expectations, sexual preference and other factors influence our actions on these unconscious drives.

       Visit this link below to watch a video on "The Science of Sex Appeal"

http://videos.howstuffworks.com/discovery/35981-science-of-sex-appeal-women-are-choosier-video.htm 

Sources:

Multimedia Resources:

http://www.pbs.org/wgbh/evolution/library/01/6/real/l_016_08.html

Sources.

Hanna Kokko, Robert brooks, Michael D. Jennions and Josephine Morley. “The
evolution of mate choice and mating biases.” http://rspb.royalsocietypublishing.org/
content/270/1515/653.full.pdf+html

Arianne Y.K. Albert and Dolph Schluter. “Selection and the origin of species.”
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Mark Ridley. Evolution. http://www.blackwellpublishing.com/ridley/a-z/
Peacocks_Tail.asp

Mate Selection - Evolutionary Factors. <http://family.jrank.org/pages/1147/Mate-Selection-Evolutionary-Factors.html>