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.
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.adherents.com/misc/paradoxEvolution.html
No comments:
Post a Comment