Antisocial punishment—punishment of pro-social cooperators—has shown to be detrimental for the efficiency of informal punishment mechanisms in public goods games. The motives behind antisocial punishment acts are not yet well understood. This article shows that inequality aversion predicts antisocial punishment in public goods games with punishment. The model by Fehr and Schmidt (Q J Econ 114(3): 817–868, 1999) allows to derive conditions under which antisocial punishment occurs. With data from three studies on public goods games with punishment I evaluate the (...) predictions. A majority of the observed antisocial punishment acts are not compatible with inequality aversion. These results suggest that the desire to equalize payoffs is not a major determinant of antisocial punishment. (shrink)

Sexual size dimorphism is generally associated with sexual selection via agonistic male competition in nonhuman primates. These primate models play an important role in understanding the origins and evolution of human behavior. Human size dimorphism is often hypothesized to be associated with high rates of male violence and polygyny. This raises the question of whether human dimorphism and patterns of male violence are inherited from a common ancestor with chimpanzees or are uniquely derived. Here I review patterns of, and causal (...) models for, dimorphism in humans and other primates. While dimorphism in primates is associated with agonistic male mate competition, a variety of factors can affect male and female size, and thereby dimorphism. The causes of human sexual size dimorphism are uncertain, and could involve several non-mutually-exclusive mechanisms, such as mate competition, resource competition, intergroup violence, and female choice. A phylogenetic reconstruction of the evolution of dimorphism, including fossil hominins, indicates that the modern human condition is derived. This suggests that at least some behavioral similarities with Pan associated with dimorphism may have arisen independently, and not directly from a common ancestor. (shrink)

.Evolutionary analysis focuses on how genes build organisms with different strategies for engaging and solving life’s challenges of survival and reproduction. One of those challenges is competing with conspecifics for limited resources including reproductive opportunities. This article will suggest that there is now good evidence for considering two dimensions of social competition. First, we will label antisocial strategies, to the extent that they tend to be self-focused, threat sensitive and aggressive, as well as using tactics of bulling, threatening, intimidating or (...) even injuring/killing competitors. Their strategic goal is to stimulate fear-inhibition, flight or submissive compliance in subordinates. Such strategies turn off and inhibit care and affiliative social interactions and motivation and they can be enacted by parents, teachers and leaders. The social signals emitted stimulate various aspects of threat processing in recipients, create stressful and highly stratified groups with a range of detrimental psychological and physiological effects. Second, in contrast, prosocial strategies seek to create relaxed and secure social interactions that enable sharing, cooperative and mutually supportive and beneficial relationships. The friendly and low/no threat social signals emitted in friendly cooperative and affiliative relationships stimulate physiological systems (e.g., oxytocin, the vagus parasympathetic system) that down regulates threat processing, enhances the immune system, facilitates frontal cortical processes and general wellbeing. This article reviews the literature pertaining to the evidence for these two dimensions of social engagement. (shrink)