Evolutionary explanation

• evolutionary theories are based on the idea that the human brain and behaviour is a product of evolution by natural selection. humans have evolved adaptations to cope with the challenges of living in social groups
• aggression is an evolved strategy for problem solving among early humans. solving these issues enhanced survival and reproductive success which led to aggressive behaviours spreading through the gene pool, as those with the traits survived and passed genes on to offspring. then, these evolved mental representations inform reponses in similar situations to those experienced by ancestors
• intra-sexual selection is when ancestral males had to compete with other males for access to females. those who used aggression successfully would've been more successful in acquiring mates and more successful in passing genes to offspring.
• evidence for sexual competition

  • Lassek and Gaulin (2009): men have 75% more muscle mass than women
  • Puts (2010): men have thicker jawbones, which may have evolved due to men hitting each other
• men fear cuckoldry since they believe raising children that aren't theirs is a waste of their resources. this contributes to the survival of a rival's genes and leaves fewer resources to invest in their own future offspring.
• the adaptive function of sexual jealousy is that men in the past that avoided cuckoldry were more reproductively successful. therefore, behaviours evolved to prevent cuckoldry
• direct guarding is when men have vigilance over their partner's behaviour. for example, keeping tabs on their whereabouts
• negative inducements is when a person makes threats of dire consequences for infidelity. for example, if a person is married, they may threaten to kill themselves if they have an affair
• Wilson et al (1995) suggested that direct guarding and negative inducements are linked to violent behaviour. women who report this behaviour being present in their relationships were more likely to have suffered physical violence. 73% of these women had needed medical attention and 53% reported that they feared for their lives
• Smith (2007) argues warfare originated not only to obtain resources but also to attract mates and forge intragroup bond