Evolutionary Behavioral Sciences

Evolutionary Behavioral Sciences Past, Present, and Why People Struggle to Establish and Maintain Intimate Relationships Menelaos Apostolou Online First Publication, June 8, 2015. http://dx.doi.org/10.1037/ebs0000052

CITATION Apostolou, M. (2015, June 8). Past, Present, and Why People Struggle to Establish and Maintain Intimate Relationships. Evolutionary Behavioral Sciences. Advance online publication. http://dx.doi.org/10.1037/ebs0000052

Evolutionary Behavioral Sciences 2015, Vol. 9, No. 3, 000

© 2015 American Psychological Association 2330-2925/15/$12.00 http://dx.doi.org/10.1037/ebs0000052

Past, Present, and Why People Struggle to Establish and Maintain Intimate Relationships Menelaos Apostolou

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

University of Nicosia Many people face difficulties or fail completely to establish and maintain long-term intimate relationships. This is puzzling because, given the evolutionary importance of mating, we would expect that evolutionary forces would have endowed most people with adaptations that promote success in intimate relationships. This does not appear to have happened, and the present paper explores the reasons why. In particular, on the basis of anthropological and historical evidence, it is argued that the mechanisms involved in mate choice were shaped by selection forces in a context where mating was regulated. The situation in which individuals have to find mates almost completely on their own, constitutes therefore an evolutionarily novel situation for which selection forces had not sufficient time to produce adaptive changes. The present paper nominates several mechanisms involved in mate choice which may not have been optimized to deal effectively with the demands of the contemporary mating context. This perspective can promote a deeper understanding of the difficulties people face in intimate relationships, and provide a sound basis for therapy to address them. Keywords: mate choice, parental choice, intimate relationships, difficulties in intimate relationships

Many individuals find it difficult or even impossible to establish and maintain long-term intimate relationships (Miller, 2011; Osgood, Ruth, Eccles, Jacobs, & Barber, 2005). For instance, a survey of 14,000 unmarried Japanese people aged 18 –34 years found that 61% of men and 49% of women were single (The Fourteenth Japanese National Fertility Survey, 2010). However, more than 80% of single people in this sample indicated that they would like to marry at some point; one of the most frequently cited reasons for not having done so already was: “not knowing how to start a relationship with a member of the opposite sex.” As a consequence of difficulties in maintaining and establishing intimate relationships, many individuals have to spend a considerable part of their adult lives single (Laumann, 2004; Osgood et al., 2005), while others never marry or have children although they would have liked to do so (Miller, 2011; U.S. Census Bureau, 2000).

In sexually reproducing species such as our own, those who fail in the mating domain are selected out of the population (Buss, 2003), which suggests that evolutionary forces should have endowed most people with adaptations that promote success in intimate relationships. This raises the question of why many individuals face difficulties in this domain. There are at least five evolutionarily informed explanations that can potentially provide an answer. To begin with, the choice of a partner has considerable consequences for biological fitness (i.e., reproductive success); for instance, choosing a partner who suffers from a serious illness is unlikely to result in a long-lasting relationship. Accordingly, selection has endowed individuals with specific mate preferences which enable them to screen prospective mates to exclude those who compromise their fitness (Buss, 1989; Buss, 2003). Individuals with serious health problems, defects, or deformities will not appeal to anyone’s mate preferences, and they are therefore likely to be excluded from mating. A second explanation has to do with sexual orientation. Although there has been intense theoretical speculation about the evolutionary purpose of homosexuality (Apostolou, 2013;

Correspondence concerning this article should be addressed to Menelaos Apostolou, Department of Social Sciences, University of Nicosia, 46 Makedonitissas Avenue, 1700 Nicosia, Cyprus. E-mail: [email protected] 1


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Kuhle & Radtke, 2013), there is currently little agreement on this subject. The fact remains, however, that a part of the population has an exclusively or primarily homosexual orientation (LeVay, 2012). This could potentially account for some proportion of those who face difficulties in intimate relationships: nonheterosexual people who are afraid of the social consequences of their sexual orientation may choose to hide it and stay out of the mating market, or they may enter in heterosexual relationships which soon fail. A third explanation has to do with the availability of potential mates. In many societies high status men monopolize women (i.e., polygyny is practiced), leaving many low status men without a partner (Frayser, 1985). Moreover, because it is usually men who go to war, prolonged military conflict can result in many men being away from home or dying, and thus, not being available as mates. In this scenario, women who do not score high on the qualities that men value in potential mates have an increasing probability of remaining single. These cases have the effect that individuals may struggle to form intimate relationships because the availability of eligible mates is limited; however, polygyny is not practiced in postindustrial societies, and recently there have not been any prolonged large scale wars. A fourth possible explanation is that selection forces have favored a reproductive strategy by which some individuals opt-out of mating and divert their resources into helping their genetic relatives to survive and reproduce. This was proposed as an explanation for homosexuality (Wilson, 1975), but it failed to find empirical support (Bobrow & Bailey, 2001; Rahman & Hull, 2005). At present, there is little evidence to support this hypothesis, but were it to apply, some individuals would primarily be interested in helping their families rather than being actively interested in forming intimate relationships, because this would interfere with the reproductive-helper strategy. These hypotheses notwithstanding, there are a considerable number of people who have no physical deformities or serious illnesses, have a heterosexual orientation and live in a context in which potential mates are available, and who actively wish to have a long-lasting intimate relationship; yet, they find doing so difficult or impossible. This is all the more surprising be-

cause many of these people not only do not have serious defects, but actually have traits which are considered desirable by the opposite sex. For example, one study followed more than 1,000 individuals over time, and found that a significant proportion of those who were single were highly educated and apparently successful in their careers (Osgood et al., 2005)—traits which are valued in a mate (Buss, 2003). More than half of the singles in this study reported wanting to be in a relationship and being unsatisfied with their dating and romantic lives. This paper argues that some of the difficulties people face in intimate relationships can be accounted for by a fifth explanation, which is based on the mismatch between ancestral and modern environments. More specifically, it is argued that selection forces have shaped the mechanisms involved in establishing and maintaining intimate relationships in an environment very different from the one prevailing in modern postindustrial societies and, as a consequence, in several instances, these mechanisms fail to meet the demands of the modern environment, resulting in difficulties in establishing and maintaining intimate relationships. The present paper develops this argument, by employing anthropological and historical evidence in order to reconstruct the ancestral environment, and demonstrate that the evolutionary pressures that have shaped mate choice mechanisms were different from the ones prevailing today. Several mechanisms which may not be able to meet the demands of the modern environment are then nominated. Finally, implications for therapy and ways to address the shortcomings of the nominated mechanisms are explored. The Ancestral Context The genus Homo appeared on earth approximately two million years ago, and for most of this period our ancestors lived in small bands of hunters and gatherers (Lee & Devore, 1968); thus, most of human evolution took place in this context (Tooby & Cosmides, 1990). About 10,000 years ago, the agropastoral revolution took place, and most of our ancestors shifted to a nonnomadic life and a mode of subsistence based on agriculture and the herding of animals (Bellwood, 2004). Human societies were to be transformed again with the Industrial Revolu-


PAST, PRESENT AND INTIMATE RELATIONSHIPS

tion, which began in 18th century Britain. But the Industrial Revolution took place too recently to have significant evolutionary consequences, meaning that the adaptations we carry with us today were shaped by evolutionary forces operating in an ancestral preindustrial context. Accordingly, identifying the mating patterns prevailing in such an environment enables a better understanding of the evolutionary pressures that have shaped the mechanisms involved in mating, and enables us to identify differences between post- and preindustrial societies, which are likely to result in several mechanisms involved in mating not being able to deal effectively with the demands of the postindustrial context. We lack direct information on ancestral hunter and gatherer mating patterns because these societies did not leave behind any written records pertaining to the first and the longer period of human evolution. Nevertheless, we have a good source of information, namely, contemporary hunters and gatherers whose mating patterns have been studied by anthropologists. The mating patterns typically found in these societies are likely to be characteristic of the hunter-gatherer way of life and, consequently, are likely to be similar to those in ancestral hunter-gatherer societies (Apostolou, 2014; Ember, 1978). Anthropological evidence indicates that in these societies mate choice was regulated (Broude & Green, 1983; Stephens, 1963). In particular, one study collected evidence from a sample of 190 contemporary foraging societies and analyzed their mating patterns (Apostolou, 2007), finding that the most common mode of long-term mating (in approximately 70% of the cases) was arranged marriage, where parents choose spouses for their children. Furthermore, in the vast majority of cases, men, mainly fathers, were in control of marriage arrangements. Courtship, where children choose their own spouses with little input from their parents, was the primary mode of marriage in less than 5% of cases. Phylogenetic analysis, which attempts to reconstruct the conditions prevailing in ancestral societies, has provided additional evidence that the patterns of mating found across contemporary hunters and gatherers (e.g., arranged marriage) were also prevalent in an-

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cestral ones (Walker, Hill, Flinn, & Ellsworth, 2011). A subsequent study found that the choice of a mate is also heavily regulated in contemporary preindustrial societies which base their subsistence on agriculture and animal husbandry (Apostolou, 2010). Another study coded the mating patterns of 16 historical agropastoral societies over a period of approximately 5,000 years, and found that in all but one of these societies the primary mode of long-term mating was arranged marriage, marriage arrangements were predominantly controlled by fathers and other male relatives, and daughters were controlled more than sons (Apostolou, 2012). In fact, in many societies where free mate choice is now the norm, similar mating patterns were prevalent until only a few generations ago (e.g., England; see Stone, 1990). Moreover, the asymmetry in parental investment, with women directing more parental investment to their children than men (e.g., pregnancy, breastfeeding), results in men competing more intensively between them for gaining access to women (Miller, 2013). One way to achieve this is to fight directly with other men (i.e., fathers, brothers, uncles, husbands, possible competitors). Puts (2010) argued that observations such as men being larger, more muscular, and more aggressive than women suggest that male intrasexual selection, where men fight each other in order to monopolize women, had been an important selection force in ancestral times, which acted also in constraining women’s capacity to exercise mate choice. In a preindustrial context there is also space for individual mate choice to be exercised. To begin with, in many societies parents consult their children before choosing a spouse for them, and individuals can exercise mate choice more freely if their parents are absent due to death or physically too weak to impose their will (Apostolou, 2010, 2014). Children may also escape from the control of their parents, or manipulate them into granting them more freedom of choice (Apostolou, 2014). Last, but not least, children can exercise choice through divorce, which exists in almost all human societies (Betzig, 1989). Overall, there is space for individual mate choice to be exercised, but this has been reduced considerably in the later stage of human


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evolution. More specifically, the agropastoral revolution resulted in much greater production of resources, which meant that ancestral agropastoral societies were wealthier than ancestral hunter-gatherer ones. In turn, this indicates that there was much more at stake for parents in choosing a mate for their children. For instance, in an agropastoral society a marriage alliance with a wealthy high status family can provide parents access to considerable resources, but this is not the case in a foraging society where fewer resources are available. Parents might therefore be motivated to strengthen their grip over their children’s mating as the resources at stake increased (Apostolou, 2010, 2014). Consistent with this, comparisons between agropastoral and hunting and gathering societies reveal that parental choice is stronger in the former, indicating that it had also been stronger in the later stages of human evolution that followed the agricultural revolution, which took place approximately 10,000 years ago (Apostolou, 2010). This is of special importance, because, as these 10,000 years are the most recent, there has not been sufficient time for evolutionary forces to eliminate the effects of selection pressures operating during this period; that is, the consequences of the evolutionary pressures exercised during that time are still with us today. The significance of the agropastoral period can be better understood in the context of William Irons’ (1998) concept of the adaptively relevant environment (ARE). The ARE of an evolved adaptation consists of those features of the environment that the mechanism must interact with in order to confer a reproductive advantage. An adaptation interacts only with a few selected elements out of the organism’s total environment in order to confer its reproductive advantage, and different adaptations interact with different features of the environment. When changes occur to the environment, which are long lasting, those adaptations having changed AREs undergo evolution, while the rest remain the same (Irons, 1998). Agropastoral revolution brought about such a permanent change; namely, the strengthening of parental choice and the weakening of individual mate choice, and this change is likely to have affected the adaptations involved in mating. In

addition, although brief in evolutionary terms, the last 10,000 years is long enough for considerable evolutionary change to have occurred to these adaptations (Cochran & Harpending, 2009). The industrial revolution also brought a permanent change to the ARE of the mechanisms involved in mating, since it has resulted into a considerable weakening of parental control over mating and an associated strengthening in individual mate choice. Nevertheless, this transition is extremely recent in evolutionary terms to have been able to eliminate the effects of selection pressures operating during the 10,000 years of preindustrial agropastoralism. It is thus unlikely to have resulted into significant changes in these mechanisms to make them better adapted to the modern conditions. The Mismatch Between Ancestral and Modern Conditions In parental-choice systems the choice of a spouse rests predominantly with parents, but children can also exercise choice through various means, such as extramarital relationships and divorce (see above). In free-choice systems the choice of a spouse rests with children, but parents can have a considerable influence on this choice, predominantly through the use of manipulation (Apostolou & Papageorgi, 2014). Thus, in parental-choice and free-choice systems, both parental choice and individual choice are exercised; the difference is that in the former systems parental choice is stronger than individual choice, while in the latter systems individual choice is stronger than parental choice. That is, individuals in both systems need to appeal to prospective parents-in-law as desirable sons- and daughters-in-law, and to prospective mates as husbands and wives; nevertheless, the former pressure is much stronger in a parental-choice system than in a free-choice system and vice versa. This difference in selection pressures may have resulted in mechanisms that have been optimized to work well in a parental-choice system (typical of ancestral preindustrial societies), and not to work very well in a free-choice system (typical of postindustrial societies). In addition, because both selection forces are present, it is expected that there is coevolution between parents’ strategies and children’s strategies. The strategies which are the products of



coevolution taking place in a parental-choice system may not work well in a free-choice system and the reverse is also true. To use one example, children value good looks more in a mate than their parents in an in-law (Apostolou, 2014). In a parental-choice system it may be optimal for children to overemphasize beauty, in order to constrain their parents from making considerable compromises on this trait: if children have a strong preference for beauty in a spouse, parents may be reluctant to accept a very unattractive individual as a spouse for their children, because this may result in a considerable negative reaction from them, such as running away, which can compromise the marriage arrangement. On the contrary, in free-mate choice systems this strong preference may not be optimal, because the choice of a mate is not determined by parents, so instead of constraining parents in making undesirable compromises for their children, this strategy can lead children to make fitness-decreasing compromises for themselves. Individuals, for instance, may compromise too much on commitment, social status, and personality traits in order to get a mate who is good looking. Thus, they may end up with a mate who is good looking, but has few resources, is abusive, and not committed to the relationship. In sum, the anthropological and historical records indicate that most human evolution took place in a context where mate choice was regulated, with parents exercising a strong influence over their children’s mating decisions, whereas many individuals today find themselves in a context where parental influence has decreased considerably, and there is much more freedom of choice. Finding a long-term mate has become a task that men and women have to undertake almost completely on their own, perhaps for the first time in human evolutionary history. To put it another way, free mate choice constitutes a novel situation, and there may not have been sufficient time for selection forces to optimize the mechanisms involved in mating to the modern context. Drawing on evolutionary reasoning, several mechanisms involved in mating which are likely to be affected by the mismatch between ancestral and modern conditions can be nominated.

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Adaptations Involved in Mating in the Postindustrial Context Personality predicts many aspects of social interaction, and this is particularly so in the domain of intimate relationships (Buss & Hawley, 2011; Figueredo, Sefcek, & Jones, 2006). As personality traits have been shaped by evolutionary forces operating in ancestral environments, it can be the case that several of these traits may impair the formation of intimate relationships in contemporary environments. For instance, traits such as introversion and shyness, can be disadvantageous where individuals have to find mates on their own, but would have had few if any negative fitness consequences in a context where marriage was the product of negotiation between families. Similarly, a need for intimacy, in a free-mate choice context, constitutes an important prerequisite for establishing and maintaining a long-term intimate relationship. For example, narcissists have a low need for intimacy, which makes them less motivated and less willing to recognize and address the shortcomings of their character in order to make the formation of long-term intimate relationships possible (Campbell & Miller, 2011). A strong need for intimacy, however, is not a primary requirement for establishing and maintaining a relationship in which the purpose of marriage is to establish useful alliances between families. In effect, evolutionary pressures on specific aspects of personality such as shyness and need for intimacy are weak where mate choice is regulated; this translates into selection forces allowing more variation in these traits, as alleles that predispose for, say, a high level of shyness, are not selected against (Fisher, 1958; Crespi & Vanderkist, 1997). Some of this variation may nevertheless be dysfunctional in a free-mating context. For instance, in an ancestral setting introverted or shy individuals would find themselves married to spouses that their parents have selected, whereas in a postindustrial context, where they have to actively seek and find their own mates, they are likely to remain single for a prolonged period of time. Conversely, traits such as humor, charm, and being easygoing make an individual a pleasant mate to be with, and promote success in intimate relationships (Buss, 2003; Kuhle, 2012); still, when it comes to mate selection, these


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traits are of less concern to parents than they are to their children (Apostolou, 2014; Perilloux, Fleischman, & Buss, 2011). This means that selection for these traits in ancestral times would have been weak, resulting in selection forces allowing considerable variation in these dimensions. In effect, there would be many individuals today scoring below the optimal level for a context in which mating is not regulated. Although low scores in these traits may not make the formation of long-term intimate relationships impossible, they can make it difficult. In summary, personality has been shaped by selection forces in a context where mating was regulated and individual mate choice was weak. The consequence of this is that today, where mating is free and there is strong individual mate choice, many individuals find themselves with personality dispositions that prevent or make difficult the formation of long-lasting intimate relationships. Evolutionary forces may not have made many individuals pleasant in character, but it is also likely that they have not made many individuals pleasant in bed. More specifically, sexual intercourse constitutes an important aspect of intimate relationships (Toates, 2014; Wincze & Carey, 2001). Several mechanisms regulate sexual intercourse which, however, were shaped under ancestral conditions, and therefore may not be able to function effectively under modern ones. Ejaculation latency time in men and sexual desire in woman are good candidates of mechanisms that may not work optimally in a free-mate choice setting. In ancestral times, where female choice was constrained by parental control over mating and male-male competition, there was not a strong need for a man to satisfy a sexual partner in order to persuade her to stay with him. In turn, this indicates that there had been weak evolutionary pressures on the mechanisms that regulate ejaculation latency time. In other words, men who ejaculated relatively quickly, allowing little time for the sexual satisfaction of their partners, were not particularly disadvantaged compared to those who ejaculated later, giving more sexual satisfaction to their partners. In consequence, selection forces have allowed considerable variation in ejaculation latency time, with some of this variation not being optimal for a free-mate choice context where

men have to sexually satisfy their partners. This nonoptimal variation in ejaculation latency time is characterized then as premature ejaculation, with about one in three men suffering from it (Laumann et al., 2005; Lewis et al., 2004). As well as making the sexual life of a couple less satisfying, leading perhaps to the dissolution of the relationship, early ejaculation also makes some men feel ashamed, so that they choose not to enter the mating market in the first place (Barnes & Eardley, 2007). Sexual desire motivates individuals to seek mates (Wallen, 1995). Nevertheless, in an ancestral context women were exchanged between men (Apostolou, 2014), and a strong female sexual desire that would motivate women to seek a mate and engage in sexual intercourse was less necessary. This suggests that selection pressures on the mechanisms that regulate sexual desire had been weak, allowing considerable variation in this trait; it is no surprise then that almost one in two women today experience low interest in sex (Shifren, Monz, Russo, Segreti, & Johannes, 2008). Low sexual desire may impair the quality and thus the length of a relationship, but it may also reduce women’s motivation to enter the mating market in the first place. Overall, selection pressures in ancestral human societies are likely to have allowed considerable variation in the functioning of mechanisms involved in sexual intercourse, with some of this variation not being optimal for a freemate choice context, resulting in some individuals opting out of the mating market or facing problems in establishing and maintaining intimate relationships. Evolutionary forces may not have made many individuals pleasant in character, and in bed, but it is also likely that they have not made many individuals pleasant to the eye. More specifically, the looks of a prospective in-law are not the primary concern of parents when they choose spouses for their children (Apostolou, 2014; Perilloux et al., 2011). Consequently, in an ancestral context there was little evolutionary pressure on individuals to look after their appearance, possibly resulting in high variation in the mechanisms regulating how much attention people place on their looks. Thus, today many individuals may not pay adequate attention to their appearance; for instance, they do not care much if they become overweight, they do not



care much about their clothing, and so on. Good looks are much more important to potential mates than to their parents (Apostolou, 2014; Perilloux et al., 2011); thus, failure to devote sufficient attention to one’s looks may have much more negative consequences in intimate relationships today in a free-mate choice setting than in an ancestral preindustrial one. That is, poor looks constitutes a considerable impediment where individuals have to attract mates on their own. It is important to clarify that it is not argued here that people do not care about their looks, but instead that they may not care enough for the demands of a free-mate choice context. In particular, individuals place much more importance on the looks of their mates than their parents on the looks of their in-laws; consequently, the transition from a context where mate choice is regulated to a context where it is freely exercised, has resulted into beauty being considerably more important and more valued in the mating market. This has caused a tremendous growth in the beauty industry, which provides individuals with products and services to help them improve their looks (Apostolou, 2011). People with predispositions not to care much about their looks would not have suffered considerable reproductive costs in ancestral societies, and would have been able to pass their predispositions to future generations. However, those in future generations who find themselves in a free-mate choice context are likely to suffer reproductive costs, since looks in this context are valued considerably more. Thus, although there may be an overall increase in the interest to improve one’s looks, some people may fall behind, which is likely to have detrimental consequences for their reproductive success. In an ancestral context, men would usually receive women from other men through arranged marriage. Successful men such as chiefs would receive more than one wife and would marry polygynously, while less successful men would receive one or even none (Frayser, 1985). It follows that there would be strong selection pressures on men to be appealing to other men as prospective in-laws, and weaker selection pressures to appeal to women as prospective mates. These pressures may have resulted in some men being predisposed to divert effort into seeking appreciation from other men instead of women. In a postindustrial context

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however, this strategy has limited reproductive benefits because women’s mating decisions are not controlled by their fathers, brothers, and uncles. Consequently, such men may devote long hours in succeeding in climbing up the social status hierarchy, leaving little time for mating effort; in an ancestral setting this might have led to polygyny and in a modern setting it is likely to lead to staying single. Physical aggression against one’s partner, usually coming from bouts of jealousy, has been hypothesized to be an adaptation that enables men to restrict their intimate partners’ sexual behavior (Buss, 2000; Goetz, Shackelford, Romero, Kaighobadi, & Miner, 2008). Such aggression makes sexual infidelity costly for a woman, reducing her motivation to cheat, protecting, in effect, men from being cuckolded. In a preindustrial context where mate choice is regulated and the interests of the family come first, and where individual rights are not well protected, such aggression may be a relatively successful strategy. Parents are also likely to accept it as long as it is not particularly harmful for their daughter, because her husband is usually their choice, and if their daughter is to engage in extramarital relationships with men of her own choice, she would put at risk the marriage that they had arranged. On the contrary, in a postindustrial context where mating is not regulated, the individual rights are well protected, and family alliances are less important, violence may be a less successful strategy for ensuring paternity. This is because women have low tolerance for violence from their partners (Bowlus & Seitz, 2006); thus, although an adaptation which predisposes to physical violence against one’s partner may decrease the risk of being cuckolded, it is also likely to increase considerably the chance of the relationship failing. Mate choice involves compromises since individuals’ mate choices are constrained by their own mate value (Li, Bailey, Kenrick, & Linsenmeier, 2002). For instance, mate-seekers who are “fives” will have a hard time attracting mates who are “tens” because the latter will not be willing to stay with individuals of a low mate value, at least not in the long-term (Li et al., 2002; Luo & Klohnen, 2005). Effective mate choice requires then that mate-seekers assess their own mate value, and then direct mating effort at prospective mates who are close to this


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value, since these are the ones whom the chances of attracting are high. Nevertheless, because in ancestral times people rarely faced the problem of finding mates on their own, selection forces have not optimized selfassessment and mate choice mechanisms for this endeavor, with the consequence being that today some individuals may overestimate or fail to take into consideration their own mate value when they seek a mate. These individuals may have unreasonable expectations or maintain very high standards which do not match their own qualities, leading them to spend their mating effort in attempting to attract unattainable mates while rejecting offers from potential mates who are closer to their own mate value. In the same vein, in ancestral societies where mate choice was regulated, one’s status and mate value was probably determined to a large extent by their family status. Thus, in modern environments, individuals might be using their family status as a proxy for their own (in internal mate-value assessment mechanisms). Since their parents are likely to have higher status than they themselves have earned, offspring may be using this to aim high and expect too much from potential mates. In postindustrial societies, the formation of an intimate relationship involves an individual approaching another individual and initiating flirting. Flirting requires several capacities, including knowing what to say and what not to say, when to say something and when not to say it, and responding appropriately to the other individual. There are several mechanisms involved in flirting, including empathy and understanding the feelings of the opposite sex (Geher & Kaufman, 2013). During most of human evolution and especially during its later stages, flirting skills were rarely necessary to establish an intimate relationship. In effect, mechanisms involved in flirting may not have been refined by evolutionary forces, making the establishment of a relationship difficult in a free-mating context. Another possible consequence of this is that individuals with poor flirting skills may have to settle for mates of much lower mate value than their own, who can be attracted with little flirting; such relationships may prove unstable since the higher mate value partners might feel that they lose from the deal. In a preindustrial context parents, in controlling their children’s mate choices, would have

screened out individuals who were unlikely to be appropriate long-term partners; for example, individuals who did not intend a long-term commitment (Apostolou, 2014). This translates into weak selection pressure exercised on children—particularly on daughters who are controlled more—to become adept at this kind of screening; that is, selection forces may have resulted in some individuals having a reduced capacity to screen effectively prospective mates on their own. One consequence of this is that today some individuals, most likely women, may become involved in relationships that are not likely to be viable in the long-term. For instance, they may engage in relationships with mates who do not intend to make a commitment, or who are not fit to be long-term partners. In summary, specific personality traits, mechanisms that regulate sexual functioning, behavioral mechanisms that allocate attention to looks and to mating effort, mechanisms which are involved in the assessment of one’s mate value, in regulating aggression, in flirting with the opposite sex, and in screening prospective mates, are adaptations which are likely not to be able to deal effectively with the demands of a context in which mate choice is not regulated. Mate-Attraction Versus Mate-Retention Mechanisms In parental-choice systems individuals are under stronger selection pressure to appeal to parents than to their children, while in freechoice systems the opposite is true. Still, in both systems individuals would need to maintain intimate relationships. On this basis it can be argued that mate-retention mechanisms, which have been shaped in parental-choice systems, may also work well in free-choice systems, something which is not the case for mateattraction/selection mechanisms. Still, although this may be true for some mechanisms, it may not be for others. In particular, in preindustrial societies where mate choice is regulated, individual rights are not well protected, while the primary consideration is not the satisfaction of individuals but the establishment of useful alliances (Apostolou, 2014). In this context, a man can, for instance, maintain a marriage by threatening his wife with severe physical punishment if she leaves



him. He may also be very jealous, physically punishing her for any undesirable contact, in order to avoid her establishing a relationship and running away with another man. Since in this context marriages are arranged, a woman is likely to be in a marriage with someone whom she does not like, making these strategies even more important for the maintenance of the relationship. Accordingly, selection forces may have favored a high jealousy and aggressive behavior toward one’s partner in a man, since this would enable him to maintain a successful relationship in a regulated-choice context. Still, in a free-choice postindustrial context, these strategies are likely to bring the opposite result, namely, the relationship to end prematurely. That is, women may not be willing to tolerate extreme jealousy and physical abuse from their partners, and they break up with them. Another consideration is that mate-retention mechanisms are expected to have evolved to enable individuals to retain fitness-increasing mates and not mates in general. Thus, individuals who find themselves having mate-attraction/selection mechanisms, which do not work effectively in a free-choice context, may end up attracting individuals who are not good for long-term mates. Their mate-retention mechanisms may then motivate them to drive these mates away. Thus, a situation can arise where individuals are trapped in a loop of making many short-term relationships, although they would like fewer and more long-lasting ones. In this case, the inability of individuals to keep a long-term relationship is not due to their materetention mechanisms not working optimally; quite the opposite actually: it is due to their mate-attraction/selection mechanisms not working optimally. Exposure to Eligible Mates In the Mate-Attraction Versus Mate-Retention Mechanisms section, the existence of strong individual mate choice has been identified as the key difference between ancestral and modern environments that creates novel challenges that several mechanisms involved in mating cannot deal with effectively. Nevertheless, this is not the only difference between ancestral and modern environments which is likely to have a negative impact on the formation of intimate relationships.

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More specifically, in postindustrial societies most people live in large cities, among strangers; while it is not uncommon for individuals to have to move to different cities or countries, away from their families and friends in order to find a job. One possible consequence of this is that people may frequently find themselves in a situation where they have a very limited social network through which they can meet eligible mates. Furthermore, modern conditions result in many people spending most of their day in their work environment, with limited time for building a social network outside work, and given that they may have to move frequently, this can result into most of their socializing to be with work colleagues. At the same time, the potential complications are likely to deter many individuals from flirting in the workplace. In addition, certain jobs attract members of one sex (Su, Rounds, & Armstrong, 2009), which means that even if flirting was to take place freely, the availability of eligible mates in the work environment is likely to be limited. Overall, in the Mate-Attraction Versus MateRetention Mechanisms section it was argued that success in intimate relationships can be predicted by how effectively one’s mechanisms can deal with the challenges of free mate choice, with the mismatch between ancestral and modern environments indicating that several individuals are likely to have a reduced capacity for doing so. In this section, it has been argued that success is also predicted by exposure to eligible mates, and that modern environments can limit such exposure. It is also likely to be an interaction between the capacity to deal effectively with the demands of free mate choice, and the exposure to eligible mates. For example, people who are introverts, shy, have poor flirting skills, and pay little attention to their looks are likely to face problems attracting mates, with this becoming much more severe if they find themselves in a situation where their social network is limited and they cannot flirt at work, and the primary places for meeting mates are bars and clubs. Implications for Therapy The inadequacy of evolved mechanisms to function effectively in a postindustrial context is likely to have costs for the individual: both direct costs and opportunity costs. To begin


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with, failure to establish a long-term relationship may result in experiencing negative feelings such as loneliness and depression (Diener & Biswas-Diener, 2008; Layard, 2005). Moreover, a dysfunctional relationship may result in experiencing negative feelings such as anger and jealousy (Buss, 2000). Accordingly, difficulties in intimate relationships can be emotionally costly for the individual. On the contrary, a functional long-term intimate relationship can be highly rewarding in terms of experiencing positive feelings such as happiness, love, and intimacy (Diener & Biswas-Diener, 2008; Layard, 2005). This means that individuals who fail to establish a successful long-term intimate relationship suffer the opportunity cost of positive feelings that they might otherwise have experienced. Accordingly, addressing the question of how to deal effectively with the shortcomings of the evolved mechanisms and respond more effectively to the challenges of the modern environment is an important one, since it offers the potential to reduce the risk of failing to establish a successful long-term intimate relationship and the costs that it entails. One recommendation is that individuals seek the assistance of a mental health professional, such as a counseling or clinical psychologist, and work on the problematic aspects of their behavior. This requires, however, that the mental health professional is evolutionarily informed in order to be able to provide a valid diagnosis; however, with a few exceptions (Nesse & Williams, 1996), the evolutionary paradigm has made little impact on clinical psychology and psychiatry. It is therefore likely that many mental health professionals will be unable to properly diagnose the problem since they may be looking in the wrong direction. For instance, they may assume that the individual has a dysfunctional thinking style (the cognitive perspective), or that their dysfunctional relationships with the opposite sex are a consequence of a dysfunctional relationship with the opposite sex parent (the psychoanalytic perspective), or life circumstances have conditioned the individual to behave in a dysfunctional way when it comes to mate selection (the behavioral perspective). Yet, in many instances it may simply be the case that an individual has inherited mechanisms which were optimized in a context where individual choice was not an

important factor in mating, and these mechanisms are not effective in a modern context in which individual choice constitutes an important factor. Correct diagnosis of the nature of the problem may enable therapists to help individuals develop and use more appropriate and effective ways of dealing with it. In particular, therapists can train individuals in skills that will enable them to override the limitations of their evolved mechanisms, and encourage them to take corrective action. For instance, therapists can teach flirting and matescreening skills, work on regulating aggression and how to divert it to more appropriate outlets, and work on personality aspects which are particularly impairing in the formation of intimate relationships. A therapist can also motivate individuals to consider and reevaluate their careers and working hours, and to propose courses of action that will increase exposure to eligible mates. In addition, therapists can prescribe drugs to deal with certain aspects of sexual dysfunction. Last, but not least, it is also necessary that new therapeutic approaches, based on the realization that many dysfunctional aspects of mating and relationship-related behaviors are due to mental mechanisms failing to cope with the demands of the modern context because they evolved in a different one, need to be developed. Such approaches should target specific mechanisms which are poorly adapted to the present environment. Conclusion Anthropological and historical evidence indicates that during most of the period of human evolution mate choice was regulated, with parents choosing long-term mates for their children. In addition, the presence of strong malemale competition further constrained the capacity of women to exercise choice. As a consequence, in an ancestral preindustrial setting there had been weak evolutionary pressures on mechanisms that have a primary role in enabling individuals to attract and retain mates. In turn, this translates into considerable variation in the functioning of these mechanisms. In a modern postindustrial context, in which mate choice is no longer regulated, some of this variation has become dysfunctional, preventing



some individuals from establishing and maintaining long-term intimate relationships. Variation means that the performance of mechanisms or adaptations can be understood in terms of a continuum rather than in terms of categories (i.e., working well—not working well). This indicates that it is not the case that the problems arising from the mismatch between ancestral and modern conditions will affect some people and will not affect others, but rather it is the case that they will affect many people to different degrees. That is to say, some people will face minor or moderate difficulties in establishing and maintaining a long-term intimate relationship, while others will face more significant ones, and some such major ones that they will be effectively excluded from the mating market. Accordingly, the arguments developed here are relevant to many people, not just to a small minority. Some further clarifications of this line of argument are needed. To begin with, although several mechanisms involved in mating which are likely to be poorly adapted to the demands of a modern environment have been nominated here, and the ways in which they may negatively affect the establishment and maintenance of intimate relationships have been explored, these are unlikely to be the only ones. Future research should draw on the evolutionary perspective to produce a more comprehensive list. Furthermore, in this paper putative mechanisms have been nominated and not identified; thus, future studies need to provide empirical evidence that these mechanisms fail to work optimally in a modern context. Last, but not least, it is not claimed that the mismatch between ancestral and modern environments is the only cause of problems in intimate relationships; it is argued that this mismatch is likely to be an important predictor of poor relationship performance, but it is by no means the only one. David Buss, a leading authority on the evolutionary psychology of mating behavior, has argued that we come from a long line of ancestors who managed to attract mates and reproduce successfully because evolutionary forces have endowed them with appropriate mechanisms that have been passed down to us (Buss, 2003). In stating this, he aimed to send a positive message to his readers: that they are equipped with what is necessary to succeed in mating. This paper takes a less optimistic posi-

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tion, but one that is better grounded in evidence of ancestral human condition. It has to be true that our ancestors were able to find mates and reproduce successfully— otherwise we would not be here—and that our ancestors were successful in mating and reproduction because they had specific mechanisms that have been passed down to us. However, it is argued that although these mechanisms worked well in our ancestors’ environment, they may not work equally well in the modern environment since this is different from the ancestral one. This is likely to result in many individuals facing problems establishing and maintaining long-term intimate relationships. An understanding of the etiology of the problem may lead to better ways of addressing it, and help individuals to make a more adaptive response to the demands of the modern environment.

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