Monday, February 28, 2022

From 2021... Self-domestication/selective migration hypothesis: Cultural differences along the individualism–collectivism dimension are driven by the out-migration of individualists from collectivist core regions of states to peripheral frontier areas

From 2021... The origins of cultural divergence: evidence from Vietnam. Hoang-Anh Ho, Peter Martinsson & Ola Olsson. Journal of Economic Growth volume 27, pages45–89. Aug 20 2021.

Abstract: Cultural norms diverge substantially across societies, often within the same country. We propose and investigate a self-domestication/selective migration hypothesis, proposing that cultural differences along the individualism–collectivism dimension are driven by the out-migration of individualistic people from collectivist core regions of states to peripheral frontier areas, and that such patterns of historical migration are reflected even in the current distribution of cultural norms. Gaining independence in 939 CE after about a thousand years of Chinese colonization, historical Vietnam emerged in the region that is now north Vietnam with a collectivist social organization. From the eleventh to the eighteenth centuries, historical Vietnam gradually expanded its territory southward to the Mekong River Delta through repeated waves of conquest and migration. Using a nationwide household survey, a population census, and a lab-in-the-field experiment, we demonstrate that areas annexed earlier to historical Vietnam are currently more prone to collectivist norms, and that these cultural norms are embodied in individual beliefs. Relying on many historical accounts, together with various robustness checks, we argue that the southward out-migration of individualistic people during the eight centuries of the territorial expansion is an important driver, among many others, of these cultural differences.


The individualism–collectivism dimension has been found to be a powerful predictor of economic and democratic development in a large sample of countries (Gorodnichenko & Roland, 201120152017). Thus, why some societies have become more collectivistic or individualistic than others is a crucial question in understanding long-run comparative development. In the present paper, we propose and investigate the selective migration hypothesis, stating that cultural differences along the individualism–collectivism dimension are driven by the out-migration of individualistic people from collectivist societies to settle down in frontier areas, and that such patterns of historical migration are reflected even in the current distribution of cultural norms. We use the territorial expansion of historical Vietnam from the eleventh to the eighteenth centuries as an ideal setting to empirically examine this hypothesis. During this period, historical Vietnam gradually expanded its territory southward along the coast from the Red River Delta to the Mekong River Delta through various waves of conquest and migration to form the country as it is today.

Our empirical analysis focuses on the ability to solve collective action problems, which is the main feature of collectivism in related economic models, by using data on voluntary contributions to public goods, which is the most typical collective action in daily living in Vietnam. Using a household survey, we find that areas annexed earlier to historical Vietnam currently have higher levels of voluntary labor contribution to public goods production. Using a population census, we also find that households in districts that were annexed earlier have a higher percentage of households with grandchildren living in them and a lower prevalence of divorced households, which are two other standard measures of individualism–collectivism traits. Conducting a public goods experiment with high school students, we find that subjects from areas annexed earlier to historical Vietnam contribute substantially more to the public good compared to subjects from areas annexed later, and that the result is mainly driven by the belief about the contributions of other subjects. Relying on various Vietnamese historical accounts, together with various robustness checks, we show that the southward out-migration of individualistic people during eight centuries of territorial expansion of historical Vietnam is an important driver behind these cultural differences.

Despite our efforts, we recognize, however, that in the current study, it is empirically challenging to completely isolate the effects of selective migration from a crowding-in of collectivist norms by a strong state or the pre-existence of individualist norms in the periphery. We leave it for future research on other areas, with access to more detailed data on historical migration patterns and attitudes, to potentially shed further light on the relative contributions of each of these interrelated mechanisms.

We believe that the present paper makes a contribution by offering an extended conceptual framework and an empirical strategy combining survey and experimental evidence for understanding long-run cultural divergence. First and foremost, the migration patterns in the distant past played a crucial role in explaining cultural differences across modern societies. As time goes on, similar processes may continue to enhance cultural differences across societies. These cultural differences may, in turn, have important implications for future levels of comparative development.

Overall, women appear to accomplish their sexual goals in digital dating arenas more than men do given a surplus of male demand

Is Dating Behavior in Digital Contexts Driven by Evolutionary Programs? A Selective Review. Jorge Ponseti, Katharina Diehl and Aglaja Valentina Stirn. Front. Psychol., February 28 2022.

Abstract: In recent years, millions of citizens all over the world have used digital dating services. It remains unknown to what extent human sexuality will be changed by this. Based on an evolutionary psychological perspective, we assume that sexual selection shaped behavioural tendencies in men and women that are designed to increase the reproductive fitness. These tendencies are referred to as sexual strategies. Males and females sexual strategies differ according to sex-dimorphic reproductive investments. We assume that this inheritance will affect human sexuality also in a digital future. To evaluate this assumption, we conducted a selective review of studies on digital dating services. Based on sexual selection theory, we derived a number of hypotheses regarding how men and women will use digital dating services typically and how the use of digital dating services might affect sexual wellbeing. Out of an initial data set of 2,568 records, we finally reviewed a set of 13 studies. These studies provided support for the notion that men and women act in the digital dating area according to sex-typical strategies. However, sometimes the circumstances of digital dating affect communication flow, e.g., in that men are even more active in establishing contacts than they are in real world conditions. Overall, women appear to accomplish their sexual goals in digital dating arenas more than men do given a surplus of male demand. Our results suggest that future human sexuality will be impacted by an interaction of both: sex-dimorphic ancient sexual strategies and new technologies.


This selective review evaluated a total of 13 cross-sectional studies on digital dating services. Evolutionary psychological reasoning and some hypotheses, which we drew from this, drove our analysis. Taken together, our selective review supports the notion that human sexuality is not going to change fundamentally on account of the rising popularity of digital dating services. The hypotheses that led our review covered four broader topics: (a) female mating preferences, (b) male mating preferences, (c) interactions between male and female mating preferences and finally, and (d) sexual wellbeing. The reviewed studies provided supporting evidence particular to hypotheses regarding mating preferences (a–c), which were derived from evolutionary psychological reasoning. Our hypotheses regarding sexual wellbeing received only partial support.

Female Mating Preferences

Some of the reviewed studies provided findings that are in accord with evolutionary psychological reasoning. These studies report that women in the digital mating market appreciate men of higher education and of white colour. Both attributes are associated with higher socio-economic status in many countries. High-status men in turn look for younger women, as one study reported. This indicates that high-status men in digital mating markets are aware of female mating preferences. Both findings (preference for high-status males and pursuit of younger women by high-status men) have previously been found in non-digital mating markets (Buss, 1989bGrammer, 1992Buss and Shackelford, 2008Iredale et al., 2008Vohs et al., 2014Ponseti et al., 2018). One of the reviewed studies concluded that men try to look taller and more powerful as they orient their selfies more often from below (Sedgewick et al., 2017). In fact, women prefer males who are physically more powerful and taller (particularly in a short-term mating context). Again, this has been found already in the non-digital mating market before (Frederick and Haselton, 2007). Obviously, men act according to female preferences for physical dominance and display as much as possible of this trait. This in turn is sexually rewarded: physically powerful men report more sexual partners than less powerful men do (Frederick and Haselton, 2007).

We assume that female mating preferences (like male mating preferences as well) are shaped by sexual selection and modulated by culture and actual conditions of the mating marked (in terms of demand and supply). The findings discussed so far indicate that humans act according to female mating preferences in (sometimes anonymous) digital dating arenas more or less similar to real-world encounters.

Male Mating Preferences

According to sexual selection theory, males have more fitness benefits from having numerous sexual partners than females do. Therefore, males are predicted to pursue more sexual partners than females. In humans, this is particularly evident when looking at gender differences regarding interest in short-term sex (Clark and Hatfield, 1989Voracek et al., 2005Gueguen, 2011). This has been found outside the digital market area previously and appears to be true in the digital dating market in the same manner (Harris and Aboujaoude, 2016Martins et al., 2016). Male fitness benefits from high numbers of sex partners and from having young sex partners given that the reproductive capacity of a young female is higher than that of an older female. Therefore, men appreciate youthfulness in their female partners much more than vice versa (Buss, 2008, S. 114). Again, what has been found in real-word mating with respect to male mating preferences is mirrored in the digital mating market (Bruch and Newman, 2018).

Interaction of Male and Female Sexual Strategies

A striking gender difference was reported by the study of Bruch and Newman in that 80% of first messages were sent by men (Bruch and Newman, 2018). Given that in the study of Bruch and Newman the numbers of male and female participants were roughly similar, the reported difference cannot be due to a limited female supply. It rather suggests that males are much more active, if not impatient, in establishing contacts. This male over-activity might be the result of both, (i) the possibility to anonymously interact with several women at the same time (driven by the strategy to find as many mates as possible and the lack of social control) and (ii) the lack of concealed signals from women that help men to focus on those mates with prospect of success. Male over-activity in turn puts females in a more comfortable position, allowing them to define the rules of the game more according to their own needs. One possible consequence of this is that women are more self-centred in their profiles and communication (Davis and Fingerman, 2016). A pattern that is pronounced in high attractive women. These women respond even less to male requests than less attractive women (Bruch and Newman, 2018). These findings are in accord with sexual selection theory predicting the higher investing sex to be choosier and the lower investing sex to be more competitive in its efforts to sexually access the higher investing sex. We predicted the respective findings for the digital mating arena because similar observations have been made in real-world scenarios previously – and, of course, because of our overall hypothesis that important variances in human mating strategies have been shaped in ancient times. However, interactions between male and female mating strategies are complicated and require a closer look, even though the data of our selective review on this was scarce. In real-word scenarios, the supply of males is an importance factor that modulates the female inclination to engage in short-term sex. If there are fewer males than females in a given mating market, females tend to be more willing to engage in short-term sex; “sex becomes cheap” (Barber, 2000Schmitt, 2005Xing et al., 2016). Conversely, “sex becomes expensive” when there is more male demand. Possibly, the observed self-centredness of women in digital dating markets is caused by the dynamic between supply and demand. As noted above, a surplus of male demand can be experienced in a mating market even if absolute numbers of males and females are equal simply because one sex is more impatient in its efforts to establish contacts.

However, it is not self-evident that a surplus of male demand in the digital (as well as in the real-world) market is only driven by male’s (ancient) strategy to find as quickly as possible as many mates as possible. In a seminal review, Baumeister and Twenge (2002) showed convincing evidence that women work together to restrict male’s sexual access to females (in order to get as much as possible in exchange for sex). One strategy is to hide, respectively, to obscure a female’s own sexual interest. Women are influenced by other women (mothers, sisters, girlfriends, etc.) which makes them feel uncomfortable when openly showing their own sexual needs. This cultural force, in addition to adaptations shaped by sexual selection and the specific conditions of anonymous digital dating, might be one further reason why 80% of first messages were sent by men.

Effects of Digital Dating Services on Sexual Wellbeing

Contrary to our expectations, we found no studies that reported high numbers of persons being victims of sexual deception (as described above). However, we found no study that investigated this topic from an evolutionary psychology viewpoint directly. Taken together, the reviewed studies provided mixed information about whether using digital dating services might lead to increased sexual wellbeing or not. In Tinder users, feelings of loneliness or low self-esteem were found quite often (Rochat et al., 2019); others reported a willingness to engage in infidelity or unprotected sex, particularly in male users of some other data bases (Harris and Aboujaoude, 2016); however, Tsai et al. (2019) found no evidence for this in their systematic review. Moreover, a systematic comparison of couples who have met online vs. offline based on a large representative sample reported no difference regarding the quality of the relationship. That is, differences concerning sexual wellbeing between the online and offline dating world might not be as big as they were sometimes assumed, maybe with the exception that some individuals with specific problems might be attracted by particular dating services. We propose that the specific interactions between personality characteristics and characteristics of certain dating services that may lead to problems of sexual wellbeing should be investigated in future research. It is possible that the benefits of digital dating services are underestimated as well. It was found that online couples are not better off than offline couples. However, it is possible that many people are in a stable relationship or experience sexual intimacy thanks to the use of digital dating.

General Limitations

The findings of this selective review are limited by the fact that the studies included in our review were not designed to test evolutionary psychological hypotheses. This has led to a type of methodological cherry-picking in the sense that we just looked at the reviewed studies for evidence that seemed to match with (or contradict) our expectations. One problem with this approach is that the samples of the reviewed studies were of quite different origins. Some studies were based on representative samples of the general population, whereas others focussed on particular individuals, e.g., Tinder users or individuals in committed relationships. Moreover, our review covers different types of dating services; some of them offer opportunities for short-term dating, whereas others focus on long-term dating. These aspects also influence the operational sex ratio. There is ample evidence in evolutionary psychology that people experience different sexual preferences and apply different strategies depending on whether they are looking for a short-term mate or a long-term mate and depending on whether there is a surplus of males or females in a given mating arena. This leads to some limitation in the reported findings given that our hypotheses were found to be proved sometimes in one sample type but not in another sample, and vice versa. In most cases this was influenced by the fact that not all studies we reviewed provided information regarding all our hypotheses.

Factors that contribute to the maintenance or decline of relationship satisfaction

Factors that contribute to the maintenance or decline of relationship satisfaction. Francesca Righetti, Ruddy Faure, Giulia Zoppolat, Andrea Meltzer & James McNulty. Nature Reviews Psychology, Feb 21 2022.

Abstract: The quality of romantic relationships influences physical and mental health. However, maintaining happy and healthy relationships is challenging; relationship satisfaction declines over time, and relationship dissolution is frequent. This raises the question of which factors contribute to the maintenance versus decline of relationship satisfaction. In this Review, we examine the key factors that have been linked to relationship satisfaction in both cross-sectional and longitudinal studies. Specifically, we describe how self-reported perceptions (subjective perceptions of the self, the partner or the relationship), implicit evaluations (automatic evaluations of one’s partner assessed indirectly) and objective indexes (demographics, life events, communication patterns and biological indexes) relate to relationship satisfaction. This synthesis suggests that self-reported perceptions are not always the most reliable predictors of longitudinal changes in relationship satisfaction. Thus, to uncover why some relationships flourish and others struggle over time, future research should not solely focus on self-reported perceptions, but also on implicit evaluations, demographics, life events, communication patterns and biological factors, and their combination.