This response shows how the socio-relational framework of expressive behaviors may be used to understand and predict social psychological processes, beyond sex differences in the expression of emotion. I use this opportunity to elaborate on several key concepts on the epigenesis of evolved social behaviors that were not fully addressed in the target article. These are: evidence of a natural history of masculine and feminine specialization (sect. R1); phenotypic plasticity and range of reactivity of social behaviors (sect. R2); exploitive and (...) protective functions of social behaviors (sect. R3); and the role of cognition in some affective responses (sect. R4). I conclude by highlighting (in sect. R5) future directions for psychological research from a socio-relational basis. (shrink)

According to kin selection theory, indirect reproductive advantages may induce individuals to care for others with whom they share genes by common descent, and the amount of care, including self-sacrifice, will increase with the proportion of genes shared. Twins represent a natural situation in which this hypothesis can be tested. Twin pairs experience the same early environment because they were born and raised at the same time and in the same family but their genetic relatedness differs depending on zygosity. We (...) compared the degree of willingness to fight and sacrifice for the co-twin among monozygotic and dizygotic pairs in a sample of 1443 same-sex and opposite-sex twins. We also analyzed the effect of the subject’s gender and that of the co-twin on those altruistic behaviors. Results partly supported the postulated explanation. MZ twins were significantly more likely than DZ twins to self-sacrifice for their co-twins, but zygosity did not affect willingness to fight for him/her. The genders of the subject and of the co-twin, not genetic relatedness, were the best predictors of aggressive altruistic intentions. (shrink)

According to kin selection theory, indirect reproductive advantages may induce individuals to care for others with whom they share genes by common descent, and the amount of care, including self-sacrifice, will increase with the proportion of genes shared. Twins represent a natural situation in which this hypothesis can be tested. Twin pairs experience the same early environment because they were born and raised at the same time and in the same family but their genetic relatedness differs depending on zygosity. We (...) compared the degree of willingness to fight and sacrifice for the co-twin among monozygotic and dizygotic pairs in a sample of 1443 same-sex and opposite-sex twins. We also analyzed the effect of the subject’s gender and that of the co-twin on those altruistic behaviors. Results partly supported the postulated explanation. MZ twins were significantly more likely than DZ twins to self-sacrifice for their co-twins, but zygosity did not affect willingness to fight for him/her. The genders of the subject and of the co-twin, not genetic relatedness, were the best predictors of aggressive altruistic intentions. (shrink)

We propose that human self-domestication favored the emergence of a less aggressive phenotype in our species, more precisely phenotype prone to replace (reactive) physical aggression with verbal aggression. In turn, the (gradual) transition to verbal aggression and to more sophisticated forms of verbal behavior favored self-domestication, with the two processes engaged in a reinforcing feedback loop, considering that verbal behavior entails not only less violence and better survival, but also more opportunities to interact longer and socialize with more conspecifics, ultimately (...) enabling the emergence of more complex forms of language. Whereas in the case of self-domestication sexual selection has been proposed to work against physical aggression traits, in the case of verbal insult the selection has been proposed to work in favor of verbal aggression. The tension between these two seemingly opposing forces gets resolved/alleviated by a tendency to replace physical aggression with verbal aggression, and with verbal behavior more generally. This also helps solve the paradox of the Self Domestication Hypothesis regarding aggression, more precisely why aggression in humans has been reduced only when it comes to reactive aggression, but not when it comes to proactive aggression, the latter exhibiting an increase with the advent of modern language. We postulate that this feedback loop was particularly important during the time period before 50 kya, arguably between 200 kya and 50 kya, when humans were not fully modern, neither in terms of their skull/brain morphology and their behavior/culture, nor in terms of their self-domestication. The novelty of our approach lies (i) in giving an active role to early forms of language in interacting with self-domestication processes; (ii) in providing specific linguistic details and functions of this early stage of grammar (including insult and humor); (iii) in supplying neurobiological, ontogenetic, and clinical evidence of a link between (reactive) aggression and (reactive) verbal behavior; (iv) in identifying a variety of proxies of the earlier stages in evolution among cognitive disorders; and (v) in identifying specific points of contact and mutual reinforcement between these two processes (self-domestication and early language evolution), including reduction in physical aggression and stress/tension, as well as sexual selection. (shrink)

Minimizing the costs that others impose upon oneself and upon those in whom one has a fitness stake, such as kin and allies, is a key adaptive problem for many organisms. Our ancestors regularly faced such adaptive problems. One solution to this problem is to impose retaliatory costs on an aggressor so that the aggressor and other observers will lower their estimates of the net benefits to be gained from exploiting the retaliator in the future. We posit that humans have (...) an evolved cognitive system that implements this strategy which we conceptualize as a revenge system. The revenge system produces a second adaptive problem: losing downstream gains from the individual on whom retaliatory costs have been imposed. We posit, consequently, a subsidiary computational system designed to restore particular relationships after cost-imposing interactions by inhibiting revenge and motivating behaviors that signal benevolence for the harmdoer. The operation of these systems depends on estimating the risk of future exploitation by the harmdoer and the expected future value of the relationship with the harmdoer. We review empirical evidence regarding the operation of these systems, discuss the causes of cultural and individual differences in their outputs, and sketch their computational architecture. (shrink)

Purpose: The main aim of the research was to analyse aggression dimensions among athletes practising martial arts and combat sports.Material and Methods: There were 219 respondents. The Buss and Perry Aggression Questionnaire in the Polish adaptation by Siekierka was applied.Results: Martial arts apprentices turned out to present a statistically significantly lower level of hostility and of the general aggression index than combat sports athletes. It turned out that lower level of aggression was noted in female participants, verbal aggression, hostility, and (...) the general aggression index. Analysis revealed that the training experience and the training rank did not differentiated the level of the respondents' particular aggression dimensions.Conclusions: It would be advisable to perform parallel analyses in other areas of Poland and take into account the respondents' education and place of residence. (shrink)

Sex differences in physical and indirect aggression have been found in many societies but, to our knowledge, have not been studied in a population of hunter-gatherers. Among Aka foragers of the Central African Republic we tested whether males physically aggressed more than females, and whether females indirectly aggressed more than males, as has been seen in other societies. We also tested predictions of an evolutionary theory of physical strength, anger, and physical aggression. We found a large male bias in physical (...) aggression. Controlling for anger, we found an adult female bias in indirect aggression. Physical strength predicted anger, which predicted hitting, although results were sensitive to the inclusion or exclusion of traditional healers, who were physically and emotionally distinct from other Aka. With some important caveats, our results generally support the predicted sex differences in physical aggression and indirect aggression, and the predicted relationships among anger, strength, and aggression. (shrink)

In the process of cultural learning, people tend to acquire mental representations and behavior from prestigious individuals over dominant ones, as prestigious individuals generously share their expertise and know-how to gain admiration, whereas dominant ones use violence, manipulation, and intimidation to enforce obedience. However, in the context of intergroup conflict, violent thoughts and behavior that are otherwise associated with dominance can hypothetically become prestigious because parochial altruists, who engage in violence against out-groups, act in the interest of their group members, (...) therefore prosocially. This shift would imply that for other in-groups, individuals behaving violently toward out-groups during intergroup conflicts become simultaneously prestigious, making them desirable cultural models to learn from. Using the mechanism of credibility enhancing displays, this article presents preliminary vignette-based evidence that violent CRED s toward out-groups during intergroup conflict increase the perceived trustworthiness of a violent cultural model. (shrink)

Many male traits are well explained by sexual selection theory as adaptations to mating competition and mate choice, whereas no unifying theory explains traits expressed more in females. Anne Campbell's “staying alive” theory proposed that human females produce stronger self-protective reactions than males to aggressive threats because self-protection tends to have higher fitness value for females than males. We examined whether Campbell's theory has more general applicability by considering whether human females respond with greater self-protectiveness than males to other threats (...) beyond aggression. We searched the literature for physiological, behavioral, and emotional responses to major physical and social threats, and found consistent support for females' responding with greater self-protectiveness than males. Females mount stronger immune responses to many pathogens; experience a lower threshold to detect, and lesser tolerance of, pain; awaken more frequently at night; express greater concern about physically dangerous stimuli; exert more effort to avoid social conflicts; exhibit a personality style more focused on life's dangers; react to threats with greater fear, disgust, and sadness; and develop more threat-based clinical conditions than males. Our findings suggest that in relation to threat, human females have relatively heightened protective reactions compared to males. The pervasiveness of this result across multiple domains suggests that general mechanisms might exist underlying females' unique adaptations. An understanding of such processes would enhance knowledge of female health and well-being. (shrink)

Benenson et al. postulate that human females evolved unique survival adaptations to facilitate maternal and grandmaternal care. This hypothesis is consistent with the broader hypothesis that female phenotypes are more ecologically optimal, but further evidence is needed to make a compelling case that sex differences in self-protection are not primarily the result of more intense sexual selection on males.