Causes of Variation in Food Preference in the Netherlands: Our study convincingly showed that genetic factors play a significant role in food preference

Causes of Variation in Food Preference in the Netherlands. Jacqueline M. Vink  et al. Twin Research and Human Genetics, Volume 23, Issue 4, pp. 195-203, Aug 2020. https://doi.org/10.1017/thg.2020.66

Abstract: Our current society is characterized by an increased availability of industrially processed foods with high salt, fat and sugar content. How is it that some people prefer these unhealthy foods while others prefer more healthy foods? It is suggested that both genetic and environmental factors play a role. The aim of this study was to (1) identify food preference clusters in the largest twin-family study into food preference to date and (2) determine the relative contribution of genetic and environmental factors to individual differences in food preference in the Netherlands. Principal component analysis was performed to identify the preference clusters by using data on food liking/disliking from 16,541 adult multiples and their family members. To estimate the heritability of food preference, the data of 7833 twins were used in structural equation models. We identified seven food preference clusters (Meat, Fish, Fruits, Vegetables, Savory snacks, Sweet snacks and Spices) and one cluster with Drinks. Broad-sense heritability (additive [A] + dominant [D] genetic factors) for these clusters varied between .36 and .60. Dominant genetic effects were found for the clusters Fruit, Fish (males only) and Spices. Quantitative sex differences were found for Meat, Fish and Savory snacks and Drinks. To conclude, our study convincingly showed that genetic factors play a significant role in food preference. A next important step is to identify these genes because genetic vulnerability for food preference is expected to be linked to actual food consumption and different diet-related disorders.

Sexual dimorphism in body clocks: The repeated pattern of dimorphic rhythmicity observed in humans & animal models suggest that these differences are not attributable simply to societal pressures on either sex

Sexual dimorphism in body clocks. Seán T. Anderson, Garret A. FitzGerald. Science  Sep 4 2020, Vol. 369, Issue 6508, pp. 1164-1165, DOI: 10.1126/science.abd4964

Abstract: Circadian rhythms, or the body clock, confer temporal structure on human behavior and physiology to align homeostatic processes with anticipated changes in the environment. Disruption of these rhythms can influence health and well-being. Chronobiological research has often failed to consider how this temporal organization may be affected by sex. The few studies that do consider how these rhythms differ between sexes suggest a dimorphism that warrants further investigation. Recent findings from both humans and animal models illustrate how the systems that generate circadian rhythms diverge between the sexes, which has potential consequences for health and resilience to changes in sleep pattern.

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The repeated pattern of dimorphic rhythmicity observed in humans and animal models suggest that these differences are not attributable simply to societal pressures on either sex. Consistent with the findings that female mice show enhanced entrainment to phase shifts, studies in rodents have shown that females tend to be more resistant to genetic and environmental circadian disruption. In ClockΔ19/Δ19 mutant mice, in which mutation of the Clock protein interferes with transcriptional regulation by the BMAL1-CLOCK heterodimer and leads to lengthening of the circadian period, females do not develop any detectable cardiac dysfunction until 21 months of age, despite male ClockΔ19/Δ19 mice showing cardiac hypertrophy and dysfunction after 12 months (14). However, in ovariectomized ClockΔ19/Δ19 mice, cardiometabolic function was impaired relative to ovariectomized controls by 8 months of age, highlighting the protective effect of estrogen.

One possible reason for the resilience to circadian disruption in females relates to their biological imperative. Resistance to the negative consequences of circadian disruption coupled with improved sleep, even when experiencing nocturnal disturbances, may facilitate their adaptation to frequent nocturnal awakenings over a sustained period, given their predominant role in nurturing offspring. The early-activity chronotypes seen in women before menopause also align with those in children.

Circadian rhythms are influenced by sex, and this interaction is remolded throughout life. In the healthy state, females often show higher-amplitude oscillations with an earlier peak in gene expression. Dimorphism can also shape the response to circadian misalignment and the downstream consequences of disruptions to normal rhythms. A chronic disruption to human circadian rhythms is shiftwork, which is associated with cardiometabolic disease and cancer. Studies have sought to clarify whether this risk is affected by sex (15), but the results are constrained by a lack of longitudinal data. There are large differences in the rhythmic regulation of the liver transcriptome between males and females, but it is unknown whether other organs show similar differences or how faithfully this translates to protein expression and function. In humans, well-controlled, longitudinal analyses of the impact of misalignment will be necessary to address the hypothesis that females are more resilient than males to the disruption of circadian function caused by shiftwork and repeated long-distance travel.

Prenatal substance exposure, socioeconomic adversity, caregiver distress/depression, & adverse family functioning and birthweight/gestational age, physical illness, uniquely predicted more risky sexual & aggressive behavior in youngsters

Early external‐environmental and internal‐health predictors of risky sexual and aggressive behavior in adolescence: An integrative approach. Bruce J. Ellis  Nila Shakiba  Daniel E. Adkins  Barry M. Lester. Developmental Psychobiology, August 31 2020. https://doi.org/10.1002/dev.22029

Abstract: External predictive adaptive response (PAR) models assume that developmental exposures to stress carry predictive information about the future state of the environment, and that development of a faster life history (LH) strategy in this context functions to match the individual to this expected harsh state. More recently internal PAR models have proposed that early somatic condition (i.e., physical health) critically regulates development of LH strategies to match expected future somatic condition. Here we test the integrative hypothesis that poor physical health mediates the relation between early adversity and faster LH strategies. Data were drawn from a longitudinal study (birth to age 16; N = 1,388) of mostly African American participants with prenatal substance exposure. Results demonstrated that both external environmental conditions early in life (prenatal substance exposure, socioeconomic adversity, caregiver distress/depression, and adverse family functioning) and internal somatic condition during preadolescence (birthweight/gestational age, physical illness) uniquely predicted the development of faster LH strategies in adolescence (as indicated by more risky sexual and aggressive behavior). Consistent with the integrative hypothesis, the effect of caregiver distress/depression on LH strategy was mostly mediated by worse physical health. Discussion highlights the implications of these findings for theory and research on stress, development, and health.

We find that school districts in locations with stronger teachers’ unions are less likely to reopen in person; also, no evidence that measures of COVID-19 risk are correlated with school reopening decisions

DeAngelis, Corey and Makridis, Christos, Are School Reopening Decisions Related to Union Influence? (September 1, 2020). SSRN: http://dx.doi.org/10.2139/ssrn.3684867

Abstract: The COVID-19 pandemic led to widespread school closures affecting millions of K-12 students in the United States in the spring of 2020. Groups representing teachers have pushed to reopen public schools virtually in the fall because of concerns about the health risks associated with reopening in person. In theory, stronger teachers’ unions may more successfully influence public school districts to reopen without in-person instruction. Using data on the reopening decisions of 835 public school districts in the United States, we find that school districts in locations with stronger teachers’ unions are less likely to reopen in person even after we control semi-parametrically for differences in local demographic characteristics. These results are robust to four measures of union strength, various potential confounding characteristics, and a further disaggregation to the county level. We also do not find evidence to suggest that measures of COVID-19 risk are correlated with school reopening decisions.

Keywords: Collective Bargaining, Coronavirus, COVID-19, Reopening, School Closures, Unions
JEL Classification: I28, I20

Who are the Conspiracy Theorists? Demographics and conspiracy theories

Who are the Conspiracy Theorists? Demographics and conspiracy theories. Steven M. Smallpage, Hugo Drochon, Joseph E. Uscinski, Casey Klofstad. In Routledge Handbook of Conspiracy Theories, eds. Michael Butter, Peter Knight. Feb 2020. https://www.taylorfrancis.com/books/e/9780429452734/chapters/10.4324/9780429452734-3_1

Abstract: This chapter aims to address conspiracy theorising across cultural contexts. It provides the only cross-nationally-representative data focusing on conspiracy theories currently available. The chapter shows how cultural context conditions conspiracy theorising and as a consequence may frustrate attempts to study conspiracy theories cross-culturally. Conspiracy beliefs are individuals’ acceptance of specific conspiracy theories as likely true. Many researchers skip the step of systematically measuring conspiracy beliefs or thinking, and instead rely on impressions. Conspiracy beliefs are partially dependent on demographic characteristics and group memberships because they cast one’s own group as a victim of other groups. If conspiracy thinking is related to feelings of marginalisation, anomia and helplessness, then higher income levels should negatively predict belief in conspiracy theories. Studying conspiracy theories is important for understanding contemporary political life. Much of the theorising of who counts as a conspiracy theorist has taken place in the USA and other English-speaking areas.

Emophilia is a trait characterized by falling in love fast, easily, & often; is associated with ignoring red flags and rushing into relationships; the Dark Triad personality traits are interpersonally toxic but considered attractive to some

Emophilia and other predictors of attraction to individuals with Dark Triad traits. Jacqueline Lechuga, Daniel N. Jones. Personality and Individual Differences, Volume 168, 1 January 2021, 110318. https://doi.org/10.1016/j.paid.2020.110318

Highlights
• Emophilia is a trait characterized by falling in love fast, easily, and often.
• Emophilia is associated with ignoring red flags and rushing into relationships.
• The Dark Triad personality traits are interpersonally toxic but considered attractive to some.
• Emophilia was the best predictor of attraction to individuals high in Dark Triad traits.

Abstract: The current research investigated the association between different relationship orientations (e.g., insecure attachment, sociosexuality, emophilia) and attraction to individuals high in different Dark Triad traits (Machiavellianism, psychopathy, narcissism). Although research has focused on general attraction to antisocial partners, less attention has been paid to traits that affect that attraction. One understudied construct in predicting relationship-relevant attraction is emophilia, which is the tendency to fall in love fast and often. Across two studies (N = 452), we found that emophilia had a strong and unique relationship with attraction to individuals high in dark personality traits. In Study 1, participants completed an assessment of the Dark Triad as they would want their “ideal romantic partner” to complete it. Participants in Study 2 rated the attractiveness of different dating profiles generated by people who varied in the Dark Triad. Participants in both studies filled out self-assessments of emophilia, sociosexuality, and attachment styles. Across both studies, people high in emophilia were the most attracted to any target, including targets high in the Dark Triad traits, even when controlling for other relationship-relevant traits. The findings have implications for relationship research, personality research, and potential risk factors for becoming involved with antisocial partners.

Keywords: AttractionDark TriadAttachment stylesEmophiliaSociosexualityMatingRelationships

6. General discussion

In two different studies, the current research investigated the association between relationship variables (emophilia, sociosexuality, attachment styles) and attraction to the different Dark Triad traits (Machiavellianism, psychopathy, narcissism). Of interest was emophilia, the tendency to fall in love fast and often. We hypothesized that emophilia would correlate with attraction to the different Dark Triad traits. In Study 1, participants who scored higher in emophilia, avoidant attachment, and sociosexuality reported increased preference for “ideal romantic partners” who scored higher in the different Dark Triad traits. However, in Study 2, using mock dating profiles, only emophilia was significantly associated with generalized attraction. In particular, individuals high in emophilia reported higher attraction to all profiles, regardless of the nature of the profile or who wrote it. In contrast, sociosexuality was associated with only the narcissistic profile.

Previous research has suggested that individuals high in the different Dark Triad traits are attractive (Carter et al., 2014; Grosz et al., 2015), especially men (Jonason et al., 2009). However, these findings may largely depend on individual differences in different relationship orientations. Among these individual differences, emophilia emerged as the strongest predictor of attraction to ideal partners high in the different Dark Triad traits, and attraction to dating profiles in a non-discriminating fashion. Thus, they recorded a generalized attraction to others, consistent with the construct definition of emophilia (e.g., Jones, 2015).

7. Implications

Attraction to Dark Triad traits is not universal among women or men. Instead, certain individuals find the characteristics and presentation of the Dark Triad traits attractive. Specifically, individuals high in different Dark Triad traits may be especially appealing to people high in emophilia. Although, for some, there may be an initial attraction to Dark Triad individuals, people high in any of the Dark Triad traits struggle with retaining partners (e.g., Webster et al., 2016). Thus, future research should examine how long individuals high in emophilia actually stay in a relationship with individuals high in different Dark Triad traits. The data also speak to the possibility that individuals high in emophilia may have a type of reproductive strategy that lends itself to short-term mating. Thus, future research should examine the relationship between emophilia and life history strategy (Figueredo, Vásquez, et al., 2006). Future research should also determine mechanism. It could be that individuals high in emophilia are attracted to dark personality partners. However, it could also be that individuals high in emophilia ignore the red flags that might indicate a partner could be problematic in the future.

8. Limitations and future directions

There are also limitations to the present research. For example, all participants were obtained from Amazon's Mechanical Turk. Objections to the usage of Amazon's Mechanical Turk often include a lack of representation of the general population (Paolacci & Chandler, 2014), repeated participation of workers (Kees et al., 2017), and workers' motivation to participate for monetary compensation (Kees et al., 2017). However, it is worth noting that our research included attention checks. Further, some workers participate in studies for an innate interest in the study (Kees et al., 2017), and overall data collected from Amazon's Mechanical Turk has demonstrated to be of good quality (Hauser & Schwarz, 2016; Kees et al., 2017; Paolacci & Chandler, 2014). Another limitation is the absence of actor-partner data. Specifically, we did not study self and other ratings of individuals who are in relationships. Additionally, most of our participants were not single. However, research has found that individuals can have ideal conceptualizations of a romantic partner's personality that is uncorrelated with their actual romantic partner. Further, the best predictor of actual relationship pair-bonding is mate quality, which includes physical and non-physical traits (Figueredo, Vásquez, et al., 2006). Therefore, individuals can still gauge the attractiveness of individuals outside of a relationship.

Another limitation to consider is the usage of mock profiles to investigate attraction to the Dark Triad. Although vignettes have previously been used successfully to assess attraction to the Dark Triad (Carter et al., 2014; Qureshi et al., 2016; Rauthmann & Kolar, 2013), it is possible that these reported preferences may not replicate on actual choices (Figueredo, Vásquez, et al., 2006; Jauk et al., 2016; Eastwick et al., 2011). Further, the differences among the profiles were subtle. For example, narcissistic interests were: “I like the outdoors, cycling, MMA, hotrods, tattoos, swimming, music shows, and roller derby. Pretty much anything fun.” These interests reflected sensation seeking and social visibility, which are consistent with narcissism. Further, these interests differed from low Dark Triad interests, which were: “Music, photography, hiking, cycling, traveling, history, movies, learning, reading, computers, and gadgets.” Nevertheless, the subtle nature of these differences likely attenuated the ability to make conclusions about attraction specifically to individuals high in different Dark Triad traits. However, the attraction observed to all four profiles among those high in emophilia, does support further validity of the construct of emophilia and the assessment. Future research should focus on a more naturalistic study design to investigate attraction for the Dark Triad.

Although we do not have any theory as to why male participants high in emophilia would respond differently, one potential limitation was the focus on women's attraction to Dark Triad profiles in men. Just as there are gender differences in Dark Triad scores (Jonason et al., 2009), there are gender differences in emophilia worth noting. Specifically, men are higher on emophilia than are women, and among men, emophilia has a higher correlation with anxious attachment (Jones, 2017). Nevertheless, we focused on women's potential attraction to Dark Triad traits in men in Study 2 because that has been the traditional focus of research on Dark Triad and mate attraction (e.g., Brewer et al., 2018; Carter et al., 2014; Marcinkowska et al., 2015; Marcinkowska et al., 2016; Qureshi et al., 2016). Further, Dark Triad traits also mediate the relationship between gender and short-term mating efforts (Jonason et al., 2009). Nevertheless, future research should delve deeper into the potential gender differences within emophilia. Finally, future research should focus on a more naturalistic study design to investigate attraction for the Dark Triad.

Future research should also examine whether emophilia is associated with attraction to other problematic personality constructs such as borderline personality or vulnerable narcissism (Miller et al., 2010). It may be the case that the charm, risk-taking, and agentic nature of individuals high in the different Dark Triad traits is uniquely attractive to individuals high in emophilia. It may also be the case that the vulnerable nature of traits such as borderline personality is also attractive to those high in emophilia. At the very least, the presence of these traits may not interfere with emophilia-based attraction. Future research should also examine emophilia-based attraction to everyday traits such as extraversion and openness to experience. Finally, research should examine the mechanisms behind emophilia-based Dark Triad attraction. For example, although superficial charm is a likely candidate, this needs to be more directly tested.

Although not assessed in the current study, vulnerable traits such as borderline personality may also be associated with increased attraction to different Dark Triad traits. Because emophilia and borderline personality have a positive correlation (i.e., r = 0.17–0.22; Jones, 2011a), there may be similar but distinct processes driving the attraction of individuals with borderline characteristics to individuals high in different Dark Triad traits.

No significant evidence that people with high trait neuroticism access social media particularly frequently or for long periods of time; also, failed to find a relationship between status update frequency & neuroticism

Understanding neuroticism and social media: A systematic review. Thomas Bowden-Green, Joanne Hinds, Adam Joinson. Personality and Individual Differences, Volume 168, 1 January 2021, 110344. https://doi.org/10.1016/j.paid.2020.110344

Abstract: Despite people spending nearly 10% of each day on social media platforms, many also now appear to be anxious to limit the intrusion of social media into their everyday lives. Given the known link between mental anguish and trait neuroticism, understanding how personality relates to social media usage has become an important area of study in recent years. As a result, there is an abundance of articles exploring neuroticism and social media across a variety of contexts. This article synthesizes and reviews the existing work, based on a systematic search that identified 159 studies. Our findings highlight that this current research is highly contradictory, for example people with high trait neuroticism report excessive use despite appearing to use social media infrequently. We discuss the key trends across existing studies to date, and we consider the apparent difficulties experienced by people with high trait neuroticism in exploiting the full benefits of ‘social’ media, discussing the importance of considerations for both designers and users of social media platforms.

Keywords: NeuroticismPersonalityBig FiveSocial media

4. Discussion

4.1. Major findings and implications

Our review highlights a number of key trends across the vast amount of research attempting to understand how neuroticism relates to social media. First, there is no significant evidence that people with high trait neuroticism access social media particularly frequently or for long periods of time. Likewise, research has failed to find a relationship between status update frequency and neuroticism. There is also no consistently reported link between reacting to the content of others through commenting or liking and neuroticism. These findings contrast with the perceptions of their own usage.

Our findings also highlight numerous contradictions within the current research. For instance, although there appears to be a clear link between neuroticism and excessive usage of social media, often identified through self-report measures (such as Hawi and Samaha, 2019), this isn't necessarily reflected in duration or frequency of use findings. Some researchers have raised concerns about self-report measures as a valid and reliable means of determining technology addiction (Coyne et al., 2020; Ellis, 2019). Ellis (2019) also hypothesized a potentially causal correlation between ‘anxiety’ and self-reported addiction. A logical conclusion to be therefore drawn from these apparently conflicting findings (excessive yet infrequent use) is that people with high trait neuroticism worry about their usage more than their actual usage warrants, reflecting the anxiety facet associated with trait neuroticism (Tackett & Lahey, 2017). In turn, their anxiety to reduce perceived ‘excessive’ use could lead to lower usage in terms of time (e.g Kuo and Tang, 2014) and/or more ‘passive’ use. Ironically though, even passive use has previously been found to reduce well-being (Verduyn et al., 2015). The concern among people with high trait neuroticism about their social media use, may actually lead to a behaviour that is further contributing to their anxiety.

In respect of the initial goal to understand how personality traits relate to the apparent harmful effects of social media (Waterson, 2019), we find a wealth of evidence to support a link between self-report measures of excessive use and neuroticism as discussed above. Therefore, given that personality traits relate to reports of problematic use, the evidence suggests that responsivity to reduction efforts may also correspond with traits. Modern ‘microtargeting’ methods (Barbu, 2014) for example, especially in this social media environment, provide the potential to tailor specific intervention messages to specific personality traits (Matz et al., 2017).

Another prominent trend is the apparent motivation of those with high trait neuroticism to use social media to socially interact (such as Eşkisu, Hoşoğlu and Rasmussen, 2017). Again, the research we identify indicates that people with high trait neuroticism have a comparatively small online social network (such as Noë, Whitaker and Allen, 2018), appearing at odds with this socialising motivation. Yet, one explanation requiring further research may be a difference in perception regarding the number of friends/contacts required to ‘socialise’. Are those with high trait neuroticism content with a smaller network? Given that trait neuroticism is generally associated with feelings of dissatisfaction towards a social group (such as Dehle & Landers, 2005), people with high trait neuroticism do not seem to particularly value networks or strive to achieve a large online social network. Another explanation could be their usage of social media in terms of content creation and reaction. The design of social media platforms/algorithms requires users to be ‘social’ and to interact through creating and sharing content. Our findings suggest that those with high trait neuroticism generally do not provide significantly high quantities of status updates (such as Cheevasuntorn et al., 2018) or react to others' content through ‘likes’ or ‘comments’ (such as Lee, Ahn and Kim, 2014). Therefore, it is unsurprising that this ‘passive’ use (Ryan and Xenos, 2011) does not attract a large following or friendship base. Furthermore, the valence of the content that is shared by people with high trait neuroticism may well play a part in their experience of social media (and vice-versa – through the virtuous circle discussed below). Previous research indicates that positive content is more attractive to online audiences (Berger & Milkman, 2012), yet the overwhelming evidence is that people with high trait neuroticism share negative valence content (such as Shen, Brdiczka and Liu, 2015). Infrequent posting of ‘positive’ content that might otherwise attract peers is therefore a third potential causal explanation of the small network size.

In some ways, there appears to be an injurious circle or self-fulfilling prophecy, with potential dissatisfaction in a network (such as Dehle & Landers, 2005) leading to a negative experience which is reflected in negative sentiment and emotion (such as Shen, Brdiczka and Liu, 2015), again limiting the extent to which those with high trait neuroticism socialise on social media. A similar pattern may be occurring with the concern for self-presentation leading to extreme caution or anxiety about the posts created and therefore a smaller quantity of posts. It seems likely that this low level of interaction may lead to a smaller network size, which may intensify the concern for self-presentation.

Ultimately, if individuals with high trait neuroticism struggle to present themselves or interact with others properly on social media, they can be left craving social interaction (such as Eşkisu, Hoşoğlu and Rasmussen, 2017) and seeking favourable self-presentation (such as Seidman, 2013), yet limited in their success with either due to facets within their personality. People with high trait neuroticism may be unable to consistently present a positive online persona that would otherwise enable them to socialise successfully. As research on self-disclosure shows, there is perhaps no ‘filter’ (or not enough of a filter) on revealing facts about themselves (such as Peluchette et al., 2015) or presenting their true (i.e. negative) feelings. Therefore, as also demonstrated offline (Lincoln et al., 2003; Russell et al., 1997; Shurgot & Knight, 2005), those with high trait neuroticism do not enjoy interactions with others and are left unsatisfied with their social support network (De Jong et al., 1999; Dehle & Landers, 2005; Suurmeijer et al., 2005; Tong et al., 2004).

In sum, these findings cast considerable doubt on the ability of users with high trait neuroticism to exploit the full benefits of ‘social’ media. This is important given the increasing reliance (or assumed reliance) on social media to disseminate information and gather viewpoints. Thus, developers of social media platforms, businesses and organisations using social media should consider these aspects when designing social media spaces that are inclusive to all types of people.

4.2. Limitations and future directions

This research is not intended to offer quantifiable means of assessing the strength of effect sizes, and instead explores key trends and nuances across these studies. There is therefore an opportunity for future research to present meta-analyses of these trends. This would also explore in greater depth, for example, the differences in outcome when different data collection techniques are employed. Greater statistical analysis might also explore the effect size when traits combine.

In addition, further studies could shed further light on the apparent inconsistency between measures of compulsive, excessive or even addictive use, yet relatively low frequency of use. For example, data could be collected for a single sample on both frequency and some measure of self-reported problematic use, to further investigate this possible difference between perception and reality. Furthermore, a related area for further research is why those with high trait neuroticism self-report ‘problematic’ social media use. Are all participants accurate or does neuroticism affect self-perception? For instance, Davidson and Ellis (2019) have previously hypothesized a causal link to anxiety, a particular facet of the neuroticism trait.

Another important topic is the finding that people with high trait neuroticism appear to have fewer friends/contacts than their counterparts. This appears to contradict motivations for using social media and suggests that they may have a different perception of what it is to be ‘sociable’ online. This is an important topic for research because the nature of ‘social’ media requires users to establish and maintain networks. For example, although all recipients may believe they are participating as required, a social media campaign inviting users to share content is likely to be less effective when targeting people with high trait neuroticism recipients rather than those who are emotionally stable. An important question therefore is whether they realise this difference.

A final, and fundamental, topic for investigation is the relationship between content creation and network size. Our findings demonstrate that people with high trait neuroticism are, on average, less frequent in their posting of status updates i.e. they are ‘passive’ users of social media. In addition, they tend to post content that is negative in valence. Either, or both, variables could offer a causal explanation of the smaller-than-average network size.

Personality traits & the propensity to protest: Higher levels of agreeableness, emotional stability, & openness to experience are significantly associated with a decreased likelihood of protest participation

Personality traits and the propensity to protest: a cross-national analysis. Yi-Bin Chang et al. Asian Journal of Political Science, Sep 1 2020. https://doi.org/10.1080/02185377.2020.1814365

Abstract: This study examines the effects of the Big Five personality traits on individual protest behaviour in cross-national context. Past studies on the relationships between personality traits and political participation have mainly focused on a single country and found inconsistent results. Using the most recent wave of the World Values Survey, this study investigates the impact of personality on individual protest participation in 20 countries using the multilevel modelling. This study provides evidence that higher levels of agreeableness, emotional stability, and openness to experience are significantly associated with a decreased likelihood of protest participation. More importantly, this study demonstrates that contextual factors can interact with personality traits to influence individual protest participation. This study suggests that the effects of personality traits on individual protest participation disparate from country to country and each country may attribute the differing results to its particular political context.

KEYWORDS: Personality, Big Five, Protest, Context, Multilevel Modelling

Prosociality: Younger givers had higher levels of well-being other than physical health, older/retired givers reported better physical health only; females had better physical health, eudaimonic well-being, & psychological malfunctioning

Hui, B. P. H., Ng, J. C. K., Berzaghi, E., Cunningham-Amos, L. A., & Kogan, A. (2020). Rewards of kindness? A meta-analysis of the link between prosociality and well-being. Psychological Bulletin, Sep 2020. https://doi.org/10.1037/bul0000298

Abstract: In recent decades, numerous studies have suggested a positive relationship between prosociality and well-being. What remains less clear are (a) what the magnitude of this relationship is, and (b) what the moderators that influence it are. To address these questions, we conducted a meta-analysis to examine the strength of the prosociality to well-being link under different operationalizations, and how a set of theoretical, demographic, and methodological variables moderate the link. While the results revealed a modest overall mean effect size (r = .13, K = 201, N = 198,213) between prosociality and well-being, this masked the substantial variability in the effect as a function of numerous moderators. In particular, the effect of prosociality on eudaimonic well-being was stronger than that on hedonic well-being. Prosociality was most strongly related to psychological functioning—showing a more modest relationship with psychological malfunctioning and physical health. Using prosociality scales was more strongly associated with well-being than using measures of volunteering/helping frequency or status. In addition, informal helping (vs. formal helping) was linked to more well-being benefits. Demographically, younger givers exhibited higher levels of well-being other than physical health, while older and retired givers reported better physical health only. Female givers showed stronger relationships between prosociality and eudaimonic well-being, psychological malfunctioning, and physical health. Methodologically, the magnitude of the link was stronger in studies using primary (vs. secondary) data and with higher methodological rigor (i.e., measurement reliability and validity). We discussed all of these results and implications and suggested directions for future research.

Low-level physiological differences in sensory processing may shape an individual’s politics: Fungiform papilla density, a proxy for taste bud density, predicts conservatism (association statistically mediated by disgust sensitivity)

Ruisch, B. C., Anderson, R. A., Inbar, Y., & Pizarro, D. A. (2020). A matter of taste: Gustatory sensitivity predicts political ideology. Journal of Personality and Social Psychology, Sep 2020. https://doi.org/10.1037/pspp0000365

Abstract: Previous research has shown that political attitudes are highly heritable, but the proximal physiological mechanisms that shape ideology remain largely unknown. Based on work suggesting possible ideological differences in genes related to low-level sensory processing, we predicted that taste (i.e., gustatory) sensitivity would be associated with political ideology. In 4 studies (combined N = 1,639) we test this hypothesis and find robust support for this association. In Studies 1–3, we find that sensitivity to the chemicals PROP and PTC—2 well established measures of taste sensitivity—are associated with greater political conservatism. In Study 4, we find that fungiform papilla density, a proxy for taste bud density, also predicts greater conservatism, and that this association is partially statistically mediated by disgust sensitivity. This work suggests that low-level physiological differences in sensory processing may shape an individual’s political attitudes.

Bus drivers were twice as willing to let white testers ride free as black testers (72% vs. 36% of the time); signals of wealth and patriotism improve minority testers’ outcomes

The Colour of a Free Ride. Redzo Mujcic, Paul Frijters. The Economic Journal, ueaa090, September 2 2020. https://doi.org/10.1093/ej/ueaa090

Abstract: We use a natural field experiment to estimate the causal effect of race on discretionary favours in the marketplace. Test customers are randomly assigned to board public buses with no money to purchase a fare, leaving the bus driver to voluntarily decide whether to offer them a free ride. Based on 1,552 transactions, we uncover strong evidence of racial bias: bus drivers were twice as willing to let white testers ride free as black testers (72% vs. 36% of the time). Signals of wealth and patriotism improve minority testers’ outcomes. Our results show that white privilege extends to unregulated daily interactions.

JEL C93 - Field ExperimentsJ15 - Economics of Minorities, Races, Indigenous Peoples, and Immigrants; Non-labor Discrimination

The roles of attractiveness and competitive abilities to understand conditionality in men’s short-term reproductive strategies

Testing strategic pluralism: The roles of attractiveness and competitive abilities to understand conditionality in men’s short-term reproductive strategies. Oriana Figueroa et al. PLoS One, August 31, 2020. https://doi.org/10.1371/journal.pone.0237315

Abstract: The decision to allocate time and energy to find multiple sexual partners or raise children is a fundamental reproductive trade-off. The Strategic Pluralism Hypothesis argues that human reproductive strategies are facultatively calibrated towards either investing in mating or parenting (or a mixture), according to the expression of features dependent on the individual's condition. This study seeks to test predictions derived from this hypothesis in a sample of 242 young men (M ± SD = 22.12 ± 3.08) from Chile’s 5th Region (33֯ south latitude). Specifically, two predictions were considered that raise questions about the relationship between traits related to physical and psychological attractiveness (fluctuating facial asymmetry and self-perception of attractiveness) and competitive skills (baseline testosterone and self-perception of fighting ability) with short-term reproductive strategies. Our results indicate that psychological features related to the self-perception of physical attractiveness are related to short-term reproductive strategies. However, no evidence was found that fluctuating facial asymmetry, basal levels of testosterone and self-perception of fighting ability were related to short-term reproductive strategies. These results support the existing evidence of the importance of physical attractiveness in calibrating men’s reproductive strategies but cast doubts about the role of fluctuating facial asymmetry. They also suggest that traits related to physical attractiveness, in comparison to competitive capabilities, play a more important role in calibrating men’s short-term reproductive strategies.

Discussion

The Strategic Pluralism Hypothesis explains the conditionality of human reproductive strategies and the resolution of the trade-off between investment in multiple partners and investment in parental care [1]. This hypothesis considers that there are biological, psychological and anthropometric factors that calibrate reproductive behavior according to the context in which the individual faces the aforementioned trade-off. This study proposes two predictions that were mainly not sustained as only an effect of self-perceived physical attractiveness on short-term sociosexual orientation was found. Our results emphasize the role of physical attractiveness in men on the unfolding of unrestricted reproductive strategies (short-term strategies at the scale of sociosexual orientation). The main result indicates that the traits of attractiveness have an effect on unrestricted reproductive strategies whereas fighting abilities do not.

The first prediction sought to determine if there is a positive relationship between traits associated with physical attractiveness and traits associated with competitive abilities with unrestricted reproductive strategies. Also, we postulated that these effects should be moderated by psychological variables related to self-perception of physical attractiveness and fighting ability, respectively. Our results suggest that only self-perceived attractiveness does affect unrestricted sociosexual orientation when evaluated with the full data set. However, we failed to show the expected effect of fluctuating facial asymmetry on unrestricted reproductive strategy either as a main effect or moderated by self-perception of physical attractiveness. Conversely to our results, some studies found evidence that fluctuating facial asymmetry is associated with the implementation of short-term reproductive strategies [20], with the number of sexual partners over one’s lifetime [50, 51], and with the perception of attractiveness [14]. Several lines of evidence may explain our contrasting results. First, despite that symmetry is associated with attractiveness, this association is weak and other facial features like averageness may play a more important role in perceived attractiveness [52]. Also, facial fluctuating asymmetry is assumed to underlie variation in facial symmetry between individuals being an indirect measure of overall symmetry. This circumstance may lessen its relationships with attractiveness. And more importantly, there exists controversy about the relationship between evolutionary relevant features and levels of fluctuating facial asymmetry [21]. If it is the case that fluctuating asymmetry is not an accurate proxy of developmental instability, the rationale about the importance of fluctuating facial asymmetry as a trait related to short-term mating strategies weakens and other variables as muscularity or strength could be better predictors of an unrestricted sociosexual orientation than fluctuating facial asymmetry [42, 53]. However, this is an unresolved issue as positive evidence about the importance of fluctuating asymmetry as a proxy of health and mating success was also reported [14]. An alternative explanation of our results is that fluctuating facial asymmetry affects unrestricted sociosexual orientation but this effect is mediated rather than moderated by psychological features. In this regard, previous investigations have found that the effects of morphological features on the psychology of unrestricted male sociosexual behavior were mediated by self and third-party perceptions of physical attractiveness [23, 54]. However, our cross-sectional design precluded us to investigated mediation relationships in an accurate way [55].

Self-perception of fighting ability was not related to unrestricted sociosexual orientation. In this regard, other studies have established a relationship between fighting and mate value [43], which is defined as “the complete set of characteristics that an individual has in a given moment and in a particular context that affects his capacity to successfully find, attract and keep a partner” [56]. According to Muñoz-Reyes et al. [43], fighting ability is associated with the mate value of a partner, which implies a positive relationship between this variable and men’s assessments of their chances of finding partners, and therefore of employing intrasexual competition strategies, which implies a high degree of self-confidence in the search for partners. It has been established that the self-perception of fighting ability is also associated with aggressive behavior [25]. These findings indicate that it is plausible to support that fighting ability is a conflict resolution mechanism in situations of intrasexual competition, which is consistent with studies that have found a positive association between traits associated with fighting abilities and reproductive success [23, 43, 57]. Despite the above evidence, our null results may indicate that self-perception of fighting ability when evaluated jointly with self-perception of attractiveness is not an important factor related to unrestricted strategies. That can be explained if we assume that mate choice or indirect competition through showing off attractive features may be more important in industrialized societies rather than the direct competition through fights.

No effect was found for baseline testosterone levels on short-term reproductive strategies. Studies have associated testosterone with the search for social status [58], self-confidence in competitive situation [39] and the adoption of dominant roles in economic environments [29]. Consequently, testosterone can be considered a social hormone associated with status-seeking and not so much with aggression in itself. Status in turn could be related to different reproductive strategies according to the way it is acquired. The relationship between testosterone and reproductive strategies has been explored in other studies and evidence has been found that favors the role of testosterone as a promoter of short-term strategies. For example, Edelstein et al. [32] found an interaction between unrestricted sociosexuality and the relational status of men and established that men in relationships with partners, but that have interest in extramarital relationships, have similar testosterone levels as those of single men, producing a positive attitude about unrestricted strategies. Puts et al. [38] established that there is a negative relationship between the number of sexual partners and baseline testosterone levels, and a positive relationship between high levels of baseline testosterone and unrestricted sociosexual psychology (desire and attitudes). Although this investigation employed a reduced version of the sociosexual orientation questionnaire [59], a relationship was found between baseline testosterone levels and an orientation toward short-term strategies. The reduced sample in the model that assesses the effect of baseline testosterone on reproductive strategies could explain the null result with respect to this variable.

Based on the second prediction, a relationship was expected between attractiveness and competitive abilities on unrestricted strategies. We failed to find that association as the effect of self-perception of attractiveness was not moderated by self-perception of fighting abilities. This result further suggests that fighting abilities do not play a major role in unrestricted sociosexual orientation both directly or moderating the effects of physical attractiveness. In addition, it is important to consider that self-perception of fighting ability may not necessarily be related to the willingness to compete for new mates, but may be also associated with the willingness to protect a current mate and the offspring. In this regard, that feature is expected to be related to more restricted sociosexual orientation reflecting a higher inversion in parental care [6].

Among the limitations of this research is the inclusion of only one anthropometric measurement (fluctuating facial asymmetry), which, although a common measurement to study physical attractiveness, could be complemented with others that are also considered attractive features and, in some cases, more important in explaining facial attractiveness [52]. Another limitation was the loss of data due to the storage of samples and handling of the testosterone kit, despite following protocols tested in other investigations. In addition, our null results of the effect of basal testosterone on sociosexuality do not preclude a potential relationship between testosterone changes elicited on a mating context and sociosexuality. Changes in testosterone levels and additional anthropometric variables associated with unrestricted strategies should be included in future research, such as facial masculinization [35], height [e.g. 60] and body mass [e.g. 42]. Finally, individuals in our study expected to participate in a competitive game and to be paid according to their performance. Despite that these tasks were performed after the measures taken for the current study; they may introduce some noise in the study.

In conclusion, the present study contributes some evidence that supports the Strategic Pluralism Hypothesis as we found that psychological features of attractiveness are related to unrestricted reproductive strategies among men. However, our results are not conclusive about the potential role of competitive skills (measured by basal levels of testosterone and self-perception of fighting ability) and the role of fluctuating facial asymmetry in explaining unrestricted reproductive strategies. These findings encourage further research on traits that may be affecting the cost-benefits balance in the reproductive trade-off that men have between maximizing the number of sexual partners and investing in parental care, and designs that allowed to investigate mediation relationships considering the importance of the relationship among anthropometric features on the self-perception (that is, psychological features) of subjects when the reproductive trade-off is solved.

The immoral behavior of poor guys was attributed to situational factors and was discounted, whereas wealthy guys’ behavior was perceived as less excusable & was attributed primarily to bad moral character

Weiner, D. S., & Laurent, S. M. (2020). The (income-adjusted) price of good behavior: Documenting the counter-intuitive, wealth-based moral judgment gap. Journal of Experimental Psychology: General. Sept 2020. https://doi.org/10.1037/xge0000952

Abstract: Poor people are punished more frequently and more severely than are wealthy people for their transgressions, suggesting that an agent’s wealth affects how they are morally evaluated. To our knowledge, this has not been tested empirically. An initial study found that people expect the poor to be judged more harshly than the wealthy. Several other experiments consistently found that the reverse was true: Poor targets were judged as less immoral than wealthy targets for the same moral violations. Explanations of this wealth-based moral judgment gap were explored, including differences in descriptive/prescriptive expectations, global anti-wealthy or pro-poor biases, and differences in how people understand and explain the behavior of wealthy and poor moral transgressors. Although the moral judgment gap is likely multiply determined, poor targets were consistently viewed as having better reasons than the wealthy to act badly. Thus, the immoral behavior of poor targets was attributed to situational factors and was discounted, whereas wealthy targets’ behavior was perceived as less excusable and was attributed primarily to bad moral character. A final study extended our findings to the domain of prosocial behavior. Consistent with a reasons-based explanation, poor targets were viewed as having better moral character than wealthy targets when their behavior benefitted others, and wealthy targets were viewed as having more extrinsic reasons to behave prosocially.

Sex differences in the use of competitive tactics have been well documented & may reflect evolved predispositions; some say these differences may be eliminated in single-sex environments; paper says the differences persist

Deaner, R. O., McClellan, A., Zeigler-Hill, V., & Benenson, J. F. (2020). Sex differences in exclusion and aggression on single-sex sports teams. Evolutionary Behavioral Sciences, Aug 2020. https://doi.org/10.1037/ebs0000247

Abstract: Sex differences in the use of competitive tactics have been well documented and may reflect evolved predispositions. Recent research, however, suggests these differences may be eliminated in single-sex environments. We addressed this possibility by surveying men and women about their recent experiences as members of college (n = 376) and high school (n = 485) single-sex sports teams. We focused on participants’ recollections of being targets of exclusion or overt aggression by their teammates. In both samples, women were significantly more likely than men to recall being excluded (college Odds Ratio [OR] = 2.88; high school OR = 1.67) and receiving overt verbal aggression (ORs = 9.15, 3.30). By contrast, women were significantly less likely than men to recall receiving overt physical aggression (ORs = 0.18, 0.14). Furthermore, as predicted by the male warrior hypothesis, compared with men, women were more likely to be excluded by (ORs = 4.2, 3.36) or to receive aggression from (ORs = 13.69, 3.61) teammates in a competitive context (i.e., game) compared with other contexts. This pattern was significant for aggression in both samples and for exclusion in the high school sample. Collectively, these results indicate that differences in the behavior of men and women persist in single-sex settings where groups must cooperate against opponents.

Check also On The Evolution of The Sex Differences in Throwing: Throwing is a Male Adaptation in Humans. Michael P. Lombardo, Robert O. Deaner. The Quarterly Review of Biology, Volume 93, Number 2, June 2018. https://www.bipartisanalliance.com/2018/05/on-evolution-of-sex-differences-in.html

Justice is (not so) blind: Effects of facial masculinity and agreeableness on perceptions of criminal guilt

Justice is (not so) blind: Effects of facial masculinity and agreeableness on perceptions of criminal guilt. Ford, K. D., Penton-Voak, I. S., & Pound, N. (2020). Justice is (not so) blind: Effects of facial masculinity and agreeableness on perceptions of criminal guilt. Evolutionary Behavioral Sciences, Aug 2020. https://doi.org/10.1037/ebs0000246

Abstract: People have a tendency to make rapid judgments about the personality of others based on their facial appearance, a tendency which could have adaptive value if it helps facilitate the avoidance of individuals disposed to exploit and/or harm the perceiver. These rapid judgments, accurate or not, have the potential to influence how individuals are treated in many areas of life, including within the criminal justice system. Previous research investigating effects of appearance on judicial proceedings has suggested that a masculine facial appearance might activate criminal stereotypes, and therefore increase the likelihood of being judged guilty of a crime. To examine how masculinity might interact with other appearance dimensions, we investigated how facial morphological masculinity and perceived agreeableness influence perceptions of criminal guilt. In an online study, 369 participants (167 men, 200 women, 2 did not say) aged 18 to 82, read 12 short fictional vignettes each describing a crime (assault, burglary, or rape) with each accompanied by the face of a man “charged” with the crime. Faces were manipulated using morphing techniques to increase or decrease levels of (a) morphological masculinity and (b) perceived agreeableness (i.e., 2 × 2 manipulations for each target face). Participants were asked to indicate in each case whether they thought the “accused” was guilty or not. Overall, facial appearance had a significant effect on the probability of being judged guilty. For each crime type, manipulations of perceived agreeableness had large effects on the probability of being judged guilty, whereas manipulations of morphological masculinity did not.

Public Significance Statement—This study investigated how facial appearance can affect whether people are perceived as likely to have committed a crime. Computer graphics techniques were used to manipulate aspects of male facial shape and the facial images were presented to volunteer participants in an online study. Manipulations of perceived agreeableness in faces had large effects on the probability of an individual being judged guilty of a hypothetical crime. However, changes to the shape of the face to make it more or less masculine did not.

Keeping an intimate relationship is challenging; common reasons are “Fading away enthusiasm,” followed by “Long work hours” and “Lack of personal time and space”

The Challenges of Keeping an Intimate Relationship: An Evolutionary Examination. Menelaos Apostolou, Yan Wang. Evolutionary Psychology, September 4, 2020. https://doi.org/10.1177/1474704920953526

Abstract: Keeping an intimate relationship is challenging, and many people face difficulties in doing so. In the current research, we have attempted to identify these difficulties, within the context of an evolutionary theoretical framework. More specifically, by using a combination of qualitative research methods in a sample of 163 Greek-speaking participants, we identified 78 such difficulties. By employing maximum likelihood analysis on the scores of 1,099 Greek-speaking participants, we classified these difficulties in 12 broader factors. The most important factor was “Fading away enthusiasm,” followed by “Long work hours” and “Lack of personal time and space.” Almost 70% of the participants indicated that at least one factor, and 41% indicated that three or more factors caused them difficulties. Significant sex effects were found for most factors, indicating that men and women differed in the importance they ascribed to these difficulties. Moreover, significant age, marital status and number of children effects were found for several factors.

Keywords: difficulties in keeping an intimate relationship, keeping an intimate relationship, mating, mismatch problem, intimate relationships

Discussion

In the current research, we have identified 78 difficulties in keeping and intimate relationship, and we have classified them in 12 broader factors. We have also found that enthusiasm and romantic feelings fading away quickly, along with long work hours and lack of personal time and space, were considered as the most important factors causing difficulties to people in keeping an intimate relationship. In addition, almost 70% of the participants indicated that at least one factor, and 41% indicated that three or more factors, caused them difficulties. Significant sex, age marital status and number of children effects were found for most of the factors.

The mismatch between ancestral and modern conditions is likely to account for many of the factors that have emerged here. In more detail, in the ancestral context, enthusiasm and intense romantic feelings would motivate people to start a relationship, and they are expected to reside as the relationship progresses. In a pre-industrial context, the support, protection and subsistence benefits would take over, providing the incentive to people to keep the relationship. The absence of these factors in the post-industrial context, makes the fading away of enthusiasm and romantic feelings impairing for keeping a relationship, as people lose the incentive to do so.

In the same vein, because in the ancestral context the benefits from having a family largely outweighed the costs of having unpleasant personality traits, positive selection forces would be relatively weak on personality traits that make an individual more pleasant as a partner. Thus, in the context of romantic relationships, several people today, are not easygoing, are selfish, insecure, clingy and aggressive, traits, which impair their capacity to keep an intimate relationship since their partners are not very willing to overlook them. For instance, being physically aggressive is not tolerated in the contemporary context where individual rights are well-protected and women are not dependent on their partners, having thus the opposite effect: Women would most likely walk away from an abusive partner. Furthermore, in ancestral human societies, people lived in extended families, meaning that they had many people around which could help them with raising their children (Hrdy, 2008). In post-industrial societies, people usually live on their own, away from their families, and they have to bear themselves the bulk of the demands for raising their children. Thus, selection forces may not have adequately prepared them to do so and keeping at the same time an intimate relationship.

The factors that we have identified in the present study, reflect also conflict between the sexes. People adopt a mixed mating strategy that involves extra-pair relationships in order to increase their own at the expense of their partners’ fitness. Accordingly, as it can be seen in the “Infidelity and abuse” factor, a partner’s adoption of such strategy makes keeping the relationship difficult. Although conceptually distinct, being physically abusive loaded to the same factor as infidelity. One possible explanation is that, a male extra-pair infidelity may be coupled with physical aggression, a strategy which, in an ancestral context, could have prevented women from walking away from their unfaithful partners. The conflict between the sexes is also reflected in factors such as “Long work hours”: Being more wealthy and successful could enable individuals, especially men, to attract higher mate value long-term partners or a higher number of casual ones. In effect, people may overemphasize on their careers in order to achieve status and wealth, neglecting their current partner.

The extracted factors reflect also the adoption of a short-term mating strategy. This is more obvious in the “Not monogamous” factor, where people indicated that they were not monogamous, and as a consequence, they tended to have unsatisfactory sexual lives when they stay long in a relationship, and for this reason tend to break up easily. This factor is also reflected in the “Fading away enthusiasm”: In order to be able to adopt a short-term mating strategy, people’s romantic feelings are expected to be intense when they meet a new partner, but to reside quickly, motivating them to look for other partners. Such calibration of behavioral mechanisms would prevent people from keeping an intimate relationship.

Sex-differences were found in almost all factors, suggesting that men and women differed in how important they considered the various difficulties. As it was originally predicted, men would be more likely to adopt a short-term and a mixed mating strategy, which would cause them difficulties in keeping an intimate relationship. These difficulties were reflected in the “Not monogamous” and the “Infidelity and abuse” factors. They were also reflected in the “Fading away enthusiasm” and the “Lack of personal time and space” factors, where men gave significantly higher scores than women. For instance, as discussed in the introduction, men’s enthusiasm may fade away quickly, so that they could move on to the next partner. Also, in order to be able to have multiple partners, men would prefer to have more freedom of movement, and less control by a partner, and these preferences reflect on the “Lack of personal time and space.” As indicated by the effect size, the largest sex-difference was found for the “Lack of effort,” which also reflects this issue as items such as “My sexual interest for my partner soon fades away” loaded there. This factor may also reflect the different evolutionary histories of men and women: During most of evolutionary time, men monopolized women by force, so they may not have evolved to have high empathy and understanding of their partners’ needs.

Significant age effects were found for several factors. As indicated by the effect size, the largest difference was for the “Bad sex” and the “Long work hours” factors. Starting from the former, older participants gave higher scores than younger ones. One possible explanation is that, the more time people spend in a relationship, the more likely it is for them to get bored having sex with the same partner. Age in this case probably acts as a proxy of the length of the relationship, with older participants being more likely to be longer in an intimate relationship than younger participants. With respect to the “Long work hours” factor, we found that older participants spent more time working and less time allocating to the partners than younger participants. One possible explanation is that, as people get older, they are more likely to advance in their careers, and have then to spend more hours working and fewer hours being with their partners.

We also found that participants who had more children gave higher scores for difficulties such as their children absorbing most of their time and energy than participants with fewer or no children. This is expected, as people would allocate less resources in child-rearing and would be less likely to disagree with their partners on how to raise their daughters and sons, if they had few or no children than if they had several children. We also found that, participants who were single and divorced, gave significantly higher scores in most factors than participants who were married and in a relationship. One possible interpretation of this finding is that, individuals who experienced more difficulties, were more likely not to be in a relationship than individuals who experienced fewer difficulties. For instance, people who did not make considerable effort to keep a relationship, were not monogamous, and they felt that a relationship constrained them, were less likely to keep an intimate relationship than people who made considerable effort, were monogamous and they did not feel that a relationship constrained them. Future research needs to investigate this finding further.

The means for all factors were below the middle of the scale (i.e., “3”), suggesting that each one on its own was not causing people considerable difficulties in keeping a relationship. Yet, each mean was accompanied by a relatively large standard deviation, indicating that there was considerable variation in these difficulties, with some people finding them very constraining and others not constraining at all. On the basis of these findings, we can argue that people will experience severe difficulties in keeping a relationship when more than one factors is present. For instance, if people are quirky, have a taste for sexual variation, and lose their enthusiasm quickly, they will face severe difficulties in keeping a relationship, but people who are say only quirky, may manage to do so more smoothly. Of course, the outcome depends also on the severity of the problem; if people are for instance extremely quirky, they will face severe difficulties in keeping a relationship even in the absence of other difficulties.

As discussed above, the difficulties that people face in keeping an intimate relationship could lead to divorce. Such difficulties could cause the termination of the relationship long before it reaches the point of marriage, leading people to remain single. They may also prolong the spells of singlehood, because people who face such difficulties may had bad experiences from being in a relationship, which could demotivate them from looking to establish new ones. Actually, one study asked participants to indicate the reasons why they were single, and found that bad experiences from previous relationships was a common reason (Apostolou, 2017b). Accordingly, studying the difficulties in keeping intimate relationships is necessary for developing interventions that could enable people to maintain an intimate relationship. A proper theoretical framework for understanding these difficulties is key for this endeavor to succeed. For instance, the evolutionary theoretical framework, developed in the current paper, indicates that most of these difficulties arise from behavioral mechanisms not being well-adapted to the modern conditions rather than from behavioral mechanisms being broken. That is, in most cases of people facing difficulties in keeping an intimate relationship, there is not an underlying pathology. In turn, possible interventions should not aim to identify and “cure” a pathology, but to enable instead people to address the limitations of their behavioral adaptations, and function better in the contemporary environment.

Our research is not without limitations. To begin with, our results were based on self-report data that are subject to several biases. In particular, people may not have an accurate perception of what causes them difficulties in keeping an intimate relationship. For instance, people may fail to recognize that they are clingy, which in turn, makes keeping a relationship difficult. Furthermore, we employed a non-probability sample, so our findings cannot be readily generalized to the population. Also, although we have employed a combination of qualitative research methods in order to identify the reasons which caused people difficulties in keeping an intimate relationship, we may not have captured all of them. Moreover, the importance ascribed to these reasons may vary with the cultural context, which indicates that cross-cultural research is required for examining cultural variation. In addition, our study is explorative and was based one sample. Consequently, the next step in this research should be to employ these results and systematically develop a theoretically-driven measure, with carefully generated items, a good and a priori specified factor structure, and good measurement properties. Finally yet importantly, we did not control for sexual orientation. Given the relatively low prevalence of homosexuality and bisexuality (LeVay, 2010), we expect that our sample was predominantly heterosexual. Accordingly, our findings may not generalize to non-heterosexual individuals.

The plethora of reasons and factors that we have identified in the current research, testify to the complexity of the phenomenon. Such complexity suggests that our work is insufficient for fully understanding the difficulties that people face in keeping an intimate relationship. It should be considered thus, as the first of the many studies which are required to understand this fascinating phenomenon.