The Current Status of the Sexual Strategies Theory - Essay Example

The article examines the Sexual Strategies Theory. It first looks at the history that led to the development of the theory and then evaluates some ofthe strengths and weaknesses of the theory and discusses some of the further work that needs to be done. One of the main points of the article is that the evolution of human sexuality is connected to evolutionary biology. History. Charles Darwin’s natural selection is the key to evolutionary theory. Since reproduction is central to evolutionary process and sexuality is the closest domain to reproduction then sexuality should be the targets of the selection process. Darwin used the phrase ‘survival of the fittest’ for natural selection. But the article points out that natural selection is not necessarily survival selection. Survival is only important as it is part of the reproduction process. Darwin made some observations that didn’t seem to be about survival, for example brilliant plumage of a bird that could not have been advantageous for survival. He also noticed that males and females of the bird were different (the males were gaudy and the females were drab) yet faced the same survival challenges. Because of these anomalies Darwin put forward a second evolutionary process which he called sexual selection which basically said that characteristics that give an organism advantage for competition for mates can evolve. He defined two processes in this evolutionary process. One is intrasexual with same-sex competing for a mate so that whatever characteristics the mate favors will evolve. The second is intersexual in which the quality is determined by the mate as desirable. Then those with that quality will have preferential advantage. Characteristics evolve for reproductive advantage acquired through successful mate competition. The theory explained a lot of Darwin’s anomalies but still was not widely accepted in Biology when he put it forward in 1871. Darwin’s theory did not explain the origin of mate choice. The next major development came in 1930 with the publication of R.A. Fisher’s book The Genetical Theory of Natural Selection. Fisher proposed the theory of ‘runaway selection’. He described evolution as a two-step process. First there is genetic variation in a trait, for example, tail length in some animals. Males with longer tails will survive more. Secondly the female has a genetic variation for their choice of tail- they prefer long tails. Therefore females will select long-tail males and bear sons with longer tails. Over generations the genes for long tails will survive and the genes for female preference for long-tailed males will survive. These two genes will co-evolve over time. This theory did not survive either and it was several decades before a new theory evolved. Triver’s theory of parental involvement followed from the two gaps to be filled in the previous theories- what drove males not females to engage in intrasexual combat and what were the contexts of mate choice. Trivers in 1972 proposed that it is the amount of parental investment that should be more selective in choice of mates. Since mothers invest more, in pregnancy, they exercise choice in variety of ways to increase survival and reproduction. Criteria for selection however depend on species, habitat and social context. The low investing sex, usually the male, has to be competitive among each other. The situation however is complex in humans as both sexes invest almost equally in parenting. These theories of sexual selection laid the groundwork for evolutionary psychology of human sexuality. The Evolution of Human Sexuality was published in 1979 by Donald Symons. Some of the major points of this theory were as follows-: 1. All products of evolution are either true adaptations, by products of adaptations or noise. An adaptation must be specifically designed to solve a particular problem. A by-product is an incidental result of this design and the noise is the random variations incidental to the functional design. 2. We should not only consider behavior in scientific scrutiny. The psychological mechanisms of the behavior are also important. For example, in a study of the short-term heterosexual encounters the data produced showed statistics of the number of encounters of males versus those of females, etc. The willingness of the partners, for example, and other psychological causes of the behavior need to be considered. Psychological mechanisms are particular and linked to a specific adaptive problem. Thus there are many psychological mechanisms existing in humans. 3. Males and females have different psychological mechanisms. The Sexual Strategies Theory followed. It believes that desire is at the center of human sexuality. This theory is examined in detail in this article starting with the assumptions of the theory, then the premises of the theory, the empirical support of the theory and some of its strength and weaknesses. There are four main assumptions of the theory: all sexual psychological mechanisms owe their existence to evolution by selection and it is the only process that is powerful enough to produce such complex mechanisms. Psychological mechanisms constitute a key locus of sexual adaptation. The psychological level of description is the key to understanding evolved mechanisms. Evolved mechanisms are sensitive to the context and are functional. They evolve in response to specific environmental contingencies. Sex differences in sexuality are predicted in domains in which males and females face different adaptive problems. The premises of the theory are as follows: the theory believes that humans have a complex repertoire of mating strategies including both long-term and short-term and that each are activated differently depending on the context of the situation. The long-term mating is characterized by the attachments between parents and the biparental care. The short-term mating occurs before settling on a long-term mate or can occur between bouts of long-term mating, usually as a brief affair. There are different adaptive problems associated with short-term and long-term mating. For example, long-term mating may involve assessment of a mate as a future partner whereas short-term mating may require the ability to identify partners who are immediately sexually accessible. Because of the differences in parenting investment, men can devote larger proportions of their mating effort to short-term mating than women. The males’ minimum investment in parenting is the single act of sex, but for women there is at least the nine months of pregnancy. The adaptive problems to be solved are therefore different for men than women. For short-term sexual strategy for men their problems are partner number, identifying sexually accessible women, identifying fertile women and a minimal commitment and investment. Men who lack the mechanisms to solve these problems would be out-reproduced. Women however must have benefits to short-term mating. These are immediate resource for themselves, mate insurance in case their long-term mate should not be available due to death, illness etc., and genetic benefits through mating with superior men. For long-term mating men face the problems of identifying reproductively valuable women, ensuring increased probability of paternity, and identifying women with good parenting skills. The women’s benefits include identifying men who would protect them, commit to a long-term relationship and have good parenting skills. Support for the theory. Empirical evidence from observations, expressed preferences, physiological studies, demographic statistics and lab tests has been collected to support the Sexual Strategies Theory. Extensive cross-cultural data has also been gathered to test the theory. This data is examined under the following topics- desire for sexual variety, long-term mate preferences, sexual jealousy, and sexual conflict. Desire for sexual variety. Men reported desiring more partners than women and would consent to sexual intercourse after a shorter meeting time with a woman. In studies where men and women were approached and asked if they would go out on a date, go back to the person’s apartment or have sex, 75% of the men agreed to have sex as opposed to 0% of the women. There were also differences in sexual fantasies and shifts in attractiveness of the opposite sex over the course of an evening in a bar. All the studies showed men as having greater desire for a variety of sex partners than women. Long-term mate preferences In a study of 37 cultures the two main characteristics for men in preference of a mate were physical attractiveness and youth. Both of these characteristics are related to fertility and reproductive value. For women the main characteristics were good financial prospects and cues that lead to resources such as ambition, industriousness and social status. The differences in the men and women were related to the different adaptive problems that they face. There were also temporal shifts in mate preference. Men in long-term strategies place premium on sexual fidelity and abhor promiscuousity (to solve the problem of uncertainty of paternity), but in short-term strategies the reverse is true where they are indifferent to sexual fidelity and even slightly desire promiscuousity, (to solve the problem of accessibility). Women in short-term strategies place great value on immediate resources (like men to spend money on them), whereas in long-term strategies they value cues to long-term providing such as a promising career. Sexual jealousy. The research shows little difference between males and females regarding jealousy; both showed jealousy in mating. However the focus of the jealousy was different where men showed jealousy for sexual infidelity whereas women responded with jealousy to emotional infidelity. The evolutionary psychologists predicted that jealousy with women it was more variable with culture and context than with men. Sexual conflict This was a major component of the theory to predict the domains in which men and women would experience conflict. The theory suggests that conflict will result in any situation where one person’s sexual strategy interferes with another person’s strategies. There are many domains in which this occurs; two are discussed in the paper. One is that women are more upset by men’s strategies that interfere with their own strategies. They are upset by the aggressiveness of the sexual approaches of men. Men on the other hand are more upset by women’s strategy of withholding sex, desiring it less frequently or holding more stringent conditions for consummation. Several studies have confirmed these reactions of men and women including a study done with newlyweds. Evaluation and critique of the theory. According to this article the theory of Sexual Strategies has withstood numerous empirical tests. The conclusions have been cross-cultural. Studies have been done in Korea, Japan, Germany and the Netherlands for example. The studies have used different methodologies such as self-reports and physiological methods. The theory therefore refutes the claim that evolutionary hypotheses cannot be tested. Nevertheless there are still several tests to be done. However the strengths of the theory are based on the following-: 1. Parsimony and internal consistency. Parsimony is explained as making few assumptions or having few basic theoretical principles account for a large number of phenomena. According to this definition Sexual Strategies Theory is quite parsimonious since desire is the central assumption and from this comes a large variety of predictions. One area where some may think that the theory should be more parsimonious is in terms of the number of psychological mechanisms it postulates. But the author disagrees and thinks that just as human anatomists and physiologists postulate many different bodily mechanisms for the many different parts of the body, it is necessary to have many psychological mechanisms in one model of the mind since selection has fashioned so many psychological mechanisms. 2. Level of empirical support. Evolutionary psychology is explicit about the assumption that psychological mechanisms are universal; as opposed to manifest behaviors which are not, as shown in the many studies. However, the author points out that even though there is such a strong empirical foundation for the theory there is still further work to be done especially in the behavior manifestations. One example is to investigate the behaviors caused as a result of jealousy. There are four weaknesses of the theory presented-: 1. there is no record of selective pressures affecting human sexuality over evolutionary time. Some selection pressures are inferred from paleontological evidence or comparative analysis but it is still difficult to reconstruct evolutionary history of prior selection. 2. there is still not enough information available on psychological mechanisms. 3. the predictive value needs to be strengthened. It is possible to examine what is necessary for a successful solution, but it is still difficult to identify in advance which solution has evolved or if in fact the most successful solution is the one that has evolved. 4. the theory is far more successful in predicting and explaining sex differences than similarities between men and women or differences within the sexes. The article concludes that the Sexual Strategy Theory is compatible with theories of biological evolution. This is a very interesting theory that is useful in explaining many of the sexual behaviors of men and women in most of today’s societies. Positive aspects of the theory include the belief that desire is at the heart of human sexuality, that humans have a large repertoire of mating strategies and that men and women have different psychological mechanisms based on the different perspectives they have on mating. Although the theory presents evidence from many cultures, it would be useful to see data from ‘non-traditional’ cultures with different beliefs of marriage, for example in polygamous cultures. The theory seems well thought out and it was helpful to read the historical background to how the theory developed. Read More