Evolutionary explanations of Aggression Flashcards
Evolutionary explanations of aggression are based on the idea that aggression is an innate trait which can be traced back to our ancestors in the Environment of Evolutionary Adaptedness (EEA).
It is proposed that aggression is an ADAPTIVE trait which has promoted survival in the past because it helped to solve problems. Males who were aggressive in the EEA were more likely ensure their genetic material was passed to future generations
sexual jealousy
Sexual jealousy is an emotional state experienced by males when they fear their partner may leave them and engage in sexual relations with another male which may lead to paternal uncertainty
Males, therefore, fear CUCKOLDRY in which they raise offspring which is not genetically theirs.
Investment in offspring which do not share the male’s genes is a waste of his resources taking time away from raising biological offspring.
Males have evolved to use MATE-RETENTION TACTICS (MRT’s) to deter their partner from leaving or cheating on them.
These strategies therefore enhance reproductive success.
Direct Guarding
Male becomes increasingly vigilant of female mate in an attempt to restrict her freedom and prevent another male “gaining access”. E.g. not letting her go out
Negative inducements
Male using aggressive threats against the female in an attempt to ward off other males and make her feel unworthy of their attention. E.g.:
threatening to attack partner if she talks to another man (inter sexual threats)
threatening to attack another man for looking at her (intra sexual threats)
Sexual jealousy is the primary cause of violence against women and those who are perceived to be threatening infidelity (i.e. looking at another man) are particularly more at risk of violence.
Women who are victims of domestic abuse often cite extreme jealousy from their male partners (Dobash & Doabsh 1984). Sexual jealousy also accounts for 17% of all cases of murder in the UK where men are predominantly the perpetrators
Warfare
Although for humans, war has extreme risks of danger and personal cost, it also has adaptive benefits of attracting mates and strengthening group bonds.
Displays of aggression in warfare indicate bravery which can be perceived as an attractive quality from a potential mate.
Male warriors in traditional societies are likely to have increased SOCIAL STATUS leading to respect from peers within the group, and have more sexual partners and offspring as a result.
Supporting evidence for evolutionary explanations of aggression and sexual jealousy
Shackleford
Research into intimate partner violence, self report techniques to investigate the use of MRTs 107 married couples. Positive correlation between reports of MRT and physical violence. Men experiencing sexual jealousy more likely to use direct guarding and negative inducement stragues and had higher violence scores
women stated emotionally manipulative males were more like to have used physical aggression against them
Wilson
showed that women whose partners were sexually jealous and did not want them to talk to other men were twice as likely to have experienced serious violence 72% requiring medical attention afterward
MRT can reliably predict aggression in males against their partners
Supporting research for evolutionary explanations of aggression and warfare
Chagon
Yanamamo tribe showed that there was constant fighting between branches of the Yanamamo for access to female mates and to improve the status of one tribe over the other.
Successful warriors had more wives and children than those who were less successful.
They also found that those who had killed in battle tended to be married, whilst those who had not killed in battle, tended to be unmarried
Aggression in warfare can predict reproductive success of a male, showing the adaptive vale of aggression
evolutionary explanations can account for gender differences in aggression
There a very few warrior female societies as females have considerably less to gain by being aggressive.
Females are more at risk from near-death situations, risking reproductive damage and loss of offspring.
Female aggression is a maladaptive trait and is therefore not practiced. An adaptive strategy for females could include engaging in verbal aggression as a way of resolving disputes, which is often what happens
can explain why women less aggressive than men
Aggression may not always be adaptive
Violent and aggressive behaviour in males is not always an adaptive trait and can be regarded as maladaptive in some circumstances. For example aggressive males could be rejected socially and not appear to be attractive to a female mate seeing as though they may have an increased risk of injury or death.
reduces the validity as contradicts idea that aggression has evolved to be beneficial
