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  • Created on: 08-03-14 18:00

Social Learning Theory:

  • Bandura believed that aggression could not be explained using traditional learning theory where only direct experience was seen as responsible for the acquisition of new behaviours. Social learning theory suggests that we also learn by observing others, and this enables us to learn the specifics of aggressive behaviour such as the forms it takes, how often it is enacted and the situations that produce it.
  • Children primarily learn their aggressive responses through observing the behaviour of role models with whom their identify , and then imitating their behaviour.
  • Children also observe the consequences of aggressive behaviour by watching others being reinforced or punished - called vicarious reinforcement. Through this, they learn which behaviours are worth repeating.
  • Bandura claimed that in order for social learning to take place, the child must form mental representations of events in their social environment, as well as the possible rewards and punishments. When appropriate opportunities arise in the future, the child will display the learned behaviour as long as the expectation of reward is greater than that of the punishment.
  • Children for whom this behaviour has been particularly disasterous in the past, have a lower sense of self-efficacy in their ability to use aggression successfully to resolve conflicts, and therefore may turn to other means.
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Social learning theory: evaluation

  • Research support for the social learning theory form Badura's Bobo doll study in which children observing aggressive and non-aggressive adult models were then tested for imitative learning in the absence of the model. It was found that 1/3 of children in the aggressive condition repeated the model's behaviour, while 0 in the non-aggressive group did.
  • However, in Bandura's later study where the role models were either punished or rewarded, it does not show whether the children in the non-aggressive condition showed low levels of aggression because the punishment prevented learning or the punishment prevented performance of the behaviour. They found that when rewarding the children who showed aggressive acts, all groups performed more imitative acts. This shows that learning does take place regardless of reinforcements, but that production of behaviour is related to selective reinforcements.
  • Research shows that SLT explains adult behaviour as well. Phillips found that daily homicide rates in the US almost always increased in the week following a major boxing match, suggesting that viewers were imitating behaviours they watched and that social learning is evident in adults as well as children.
  • A major strength of SLT is that, unlike operant conditioning theory, it can explain aggressive behaviour in the absence of direct reinforcement. Although Badura's participants bhaved more aggressivley after observing an aggressive model, at no point were the children directly rewarded for their actions, therefore concept of vicarious learning is necessary in explaining the findings.
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social learning theory: evaluation

  • SLT can be used to explain cultural differences in aggression.Among the tribe of the Kalahari desert, aggression is fairly rare because of the child-rearing practices. When the child argues or fights, the parents neither reward or punish them, but physically seperate them and distract them. Also, parents do not use physical punishment, and aggressive postures are avoided. The absence of direct reinforcement of aggressive behaviour as well as the absence of aggressive models means there is little opportunity to acquire aggressive behaviours.
  • Ethical issues make it difficult to test SLT experimentally. Exposing children to aggressive behaviour with the knowledge that they may reproduce it raises ethical issues of protection against physical and psychological harm. Therefore, it is difficult to test experimental hypotheses abut the social learning of aggressive behaviour in children, and consequently difficult to establish scientific credibility of the theory.
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  • Deindividuation is a psychological state characterised by lowered self-evaluation and decreased concerns about evaluation by others.
  • It occurs when you lose a sense of personal identity through being in a crowd as there is a sense of anonymity. According to Zimbardo, being part of a crowd can diminish awareness of our own individuality and the larger the group, the greater the anonymity.
  • Deindividuation can often lead to an increase in behaviour that would normally be inhibited by personal or social norms due to there being a reduced fear of negative evaluation of actions.
  • One such consequence of deindividuation is aggression.
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Deindividuation: evaluation

  • Research supporting the link between deindividuation and increased aggression comes from Zimbardo in which undergraduates were required to deliver electric shocks to another student to 'aid learning'. Half the pps wore lab coats and hoods to hide their faces, sat in separate cubicles and were never referred to by name. The other half wore their normal clothes and wore large name tags, and sat in the same room. Pps in the deindividuation condition shocked the learner for twice as long as the identifiable pps suggesting that anonymity increased aggression.
  • However, Johnson suggested that rather than deindividuation automatically increasing aggression, the behaviour produced could be a product of local group norms. They used the same experimental conditions as Zimbardo but this time, some participants were made anonymous by means of a mask and overalls and others by means of a nurses' uniform. He found that pps shocked more than the control condition when in the overalls and mask, but actually shocked less than the controls when dressed in nurses' uniform. This shows that people respond to normative cues associated with the social context in which they find themselves. Those dressed in the mask and overalls (similar to the uniform of the Ku Klux Klan) felt that more aggressive behaviour was more appropriate than tose dressed as nurses.
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Deindividuation: evaluation

  • Dramatic support for the link between deindividuation and aggression also comes from Watson who collected data from 23 societies and found that those who changed their appearance (e.g. paints, tribal costumes) before going to war were more destructive towards their victims compared to those who did not.
  • However, evidence for the deindividuation theory itself is mixed. A meta-analysis of 60 studies of deindividuation concludes that there is insufficient support for the major claims of the deindividuation theory. For example, there was not much evidence that deindividuation is associated with reduced self-awareness or aggressive behaviour.
  • Cannavale found that male and female groups respond differently under deindividuation conditions reflecting a gender bias in the theory. An increase in aggression was obtained only in all-male groups. Diener also found greater disinhibition of aggression in males. Therefore, indicating that males may be more prone to disinhibition of aggressive behaviour when deindividuated, than females.
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Institutional aggression: within groups

  • One type of institutional aggression is that within groups such as in prisons.
  • Irwin claims that prisoners bring their own social histories and traits with them into prison, and this influences their adaptation to the prison environment.
  • Within prison environments, gang membership is consistently related to violence and other forms of antisocial behaviour. Several studies have found that gang members are more likely to engage in acts of prison violence. Huff found that gang members in the US were ten times more likely to commit a murder and three times mre likely to assault someone than were non-gang members of similar background.
  • Sykes described the specific deprivations that inmates experience within prisons that might be linked to an increase in violence. These include loss of liberty, the loss of autonomy and loss of security.
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Institutional aggression: within groups Evaluation

  • Evidence from DeLisi challenges the claim that pre-prison gang membership predicts violence whilst in prison. He found that inmates with prior street gang envolvement were no more likely than other inmates to engage in prison violence.
  • However, this lack of correlation between the two might be explained by the fact that violent gang members tend to be isolated from the general inmate population, therefore, greatly restricting their opportunities for violence. Fore example, Fischer found that isolating gang members in a special management unit reduced the rates of serious assault by 50%.
  • There is substantial research evidence to support the claim that peer violence is used to relieve the deprivation imposed by institutional cultures such as prisons. McCorkle found that overcrowding, lack of privacy and lack of meaningful activity all significantly influence peer violence. However, research in this area is not consistent in its findings. Research in psychiatric institutions for example found that increased personal space failed to decrease the level of violent incidents among patients.
  • Research has found that the deprivation model is better at explaning violence against prison staff whereas the importation model was better at explaining violence against other inmates.
  • A real-world application of the deprivation model happened at HMP Woodhill in 1990s. Wilson reasoned that if most violence occurred when it is hot, noisy and overcrowded, then it could be avoided by reducing these factors. He did and this virtually erradicated assaults, but political pressure led to units developing in different direction.
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Institutional aggression: between groups

  • In some cases, 'institution' mat refer to a whole section of society defined by ethnicity, religion or another feature. Violence may occur when one institution's relationship with another is characterised by hatred and hostility. Examples of this form of institutional aggression are the murder of 6 million Jews by the Nazis and the murder to 800,000 Tutsi by Hutu extremists.
  • Staub outlined 5 stages in the process of genocide that explain how difficult social conditions can rapidly escalate into victimisation of a target group.
  • Although human beings usually have moral inhibitions about killing fellow humans, this changes if the target grouo is dehumanied so its members are seen as worthless and therefore not worthy of moral consideration.
  • Milgran believed that the Holocaust was primarily the result of situational pressures that forced Nazi soldiers to obey their leaders regardless of any personal repugnance.
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Institutional aggression: between groups Evaluatio

  • Staub's model emphasises the importance of bystander intervention in preventing genocide. Doing nothing, it appears, simply allows the killing to continue unrestricted, and may even escalate it.
  • However, bystander intervention doesn’t necessarily end institutional aggression, as there is an important difference between the effect of intervention on duration and on severity of violence. In international or civil conflict, although intervention by outside agencies such as the UN can shortena conflict, it might also speed up criminals to step up their genocidal policy within that period of time. For example, in the Rwanden genocide 800,000 people died in just 100 days, a shocking rate of 8,000 deaths per day.
  • Evidence for the destructive consequences of dehumanisation can be seen in many conflicts such as the Jews in the Holocaust. However, dehumanisation may also explain violence against immigrants, seen by some as ‘polluting threats to the social order’.
  • Mandel rejects Milgram’s claims that obedience to authority was sufficient to explain the behaviour of Holocaust committers. He argues that Milgram’s account is monocausal and simply doesn’t match the historical record. For example, Goldhagen (1996) suggests that the main causal factor in the killings was a form of anti-Semitism so deeply fixed in the Germans at that time that they indirectly ignored the removal of millions of innocent Jews.
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Institutional aggression: between groups Evaluatio

  • Recent research suggests that personality may play an important role in this respect. Social Dominance Orientation (SDO) is a personality variable which predicts social and political attitudes. People who are high in SDO authorise social hierarchies and inter-group inequality, and see the world as ‘competitive jungle’.
  • Esses has shown that individuals high in SDO have a tendency to dehumanise outgroup members, and in particular foreign refugees and asylum seekers. 
  • These negative attitudes become rationalised through ‘legitimising myths’ which indicate to the high SDO individuals that these groups deserve our hostility because they are somehow less human than others.
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Neural and Hormonal Mechanisms: Serotonin

  • Serotonin is thought to reduce aggression by inhibitingresponses to emotional stimuli that might otherwise lead to an aggressive response. Low levels of serotonin in the brain have been associated with an increased susceptibility of impulsive behaviour and aggression. Some drugs are thought to alter serotonin levels and thus increase aggresive behaviour. Mann gave healthy subjects a drug known to deplete serotonin. Using a questionnaire to assess hostility and aggression levels, he found that the drug treatment was associated with an increase in hostility and aggression scores in males.
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N&H Mechanisms: Serotonin evaluation

  • Studies such as that of Raleigh support the importance of serotonin in aggressive behaviour in a study of vervet monkeys. They found that those fed on diets high in tryptophan which increases serotonin levels in the brain exhibited decreased levels of aggression. This suggests that the difference in aggression could be attributed to their serotonin levels.
  • Also, drugs that clinically raise serotonin levels should therefore produce a lowering in aggression. Bond found evidence for this in studies of antidepressant drugs that elevate serotonin levels. She established that such drugs tend to reduce inpulsive aggression.
  • Other evidence for the importance of serotonin in aggression has shown that in animals that are bred for domestication, there is a corresponding increase in brain concentrations of serotonin over generations, showing why domesticated animals have lower levels of aggression.
  • The links between serotonin and aggression are weel established in non-human animals. However, the link is not quite so clear in the case of humans. The complexity of human social behaviour means that a biological explanation for human aggression is insuffiecient on its own to explain the different aspects of aggressive behaviour.
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Neural and Hormonal: dopamine

  • Although the link between high levels of dopamine and aggressive behaviour is not as well established, there is some evidence to suggest that such a link exists. For example antipsychotics which reduce dopamine activity in the brain have been shown to reduce aggressive behaviour in violent delinquents.
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N&H Mechanisms: dopamine evaluation

  • Although research is fairly inconclusive about the role of dopamine in aggression, research suggests that its influence might be as a consequence instead of a cause. Kennedy found that in mice, a pathway in the brain becomes engaged in response to an aggressive event and that dopamine is involved as a positive reinforcer in this pathway. This suggests that individuals will intentionally seek out an aggressive encounter solely because they experience a rewarding sensation from it.
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Neural and Hormonal Mechanisms: testosterone

  • The male sex hormone testosterone is thought to influence aggression from young adulthood onwards due to its action on brain areas involved in controlling aggression. Evidence for this association comes from a number of sources such as that of Dabbs who measured salivary testosterone levels in violent and non-violent criminals and found that those with the highest testosterone levels had a history of violent crimes whereas those with low levels had committed only non-violent crimes. Studies of non-prison populations have found similar results such as that of Lindman who found that young males who behaved aggressively when drunk had higher testosterone levels than those who did not act aggressively.
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N&H Mechanisms: testosterone evaluation

  • A meta-analysis of 45 studies has established a mean correlation of 0.14 between testosterone and aggression, however, Archer claims that methodological problems with this study meant that a correlation of 0.08 was more appropriate.
  • Albert claims that despite many studies showing a positive correlation between testosterone and aggression, other studies find no such relationship, particularly those that have compared testosterone levels in aggressive and less aggressive individuals. In addition, most studies showing a positive correaltion have involved small samples of men within prisons, using either self-report measures of aggression or judgements based solely on the severity of the crime committed.
  • Mazur suggests that we should distinguish aggression from dominance. Individuals act aggressively when their intent is to inflict injury, whereas they act dominantly if their wish is to achieve or mainatin status. Therefore, he claims that aggression is just one form of dominance behaviour. In non-human animals, the influence of testosterone on dominance behaviour might be shown in aggressive behaviour. In humans, however, the influence of testosterone on dominance is likely to be expressed in more varied and subtle ways.
  • Most studies have involved male participants, however, in anything, research suggests that the association is higher in females than male samples. Women with higher testosterone levels had higher occupational status possibly as a result of being more assertive. These studies indicate that women may also respond to challenging situations with increased testosterone, displaying characteristics such as aggressiveness and dominance.
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Neural and Hormonal Mechanisms: cortisol

  • Cortisol appears to have a mediating effect on other aggression-related hormones such as testosterone, possibly because it increases anxiety and the likelihood of social withdrawal. High levels of cortisol inhibit testosterone levels and so inhibit aggression. Studies have reported low levels of cortisol in violent offenders and violent school children. This suggests that although relatively high testosterone is the primary biochemical influence on aggression, low cortisol also plays an importanat role by increasing the likelihood of aggressive behaviour.
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N&H Mechanisms: cortisol

  • The moderating effect of cortisol on aggressive behaviour is supported in a longitudinal study of boys with behavioural problems. Those boys with consistently low levels os cortisol bgan anti-social acts at a younger age and exhibited 3x the number of aggressive symptoms, compared to boys with higher cortisol levels. Researchers concluded that cortisol levels were strongly and inversely related to aggressive conduct disorder.
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Genetic factors in aggression:

  • The role of genetic factors in aggression can be tested in twin studies. One of the few studies to specifically study aggresive behaviour using twin pairs found that 50% of the varience in direct aggressive behaviour could be attributed to genetic factors.
  • Adoption studies can help determine the relative contributions of environment and heredity in aggression. Positive correlation between adopted children and their biological parents implies a genetic effect, while positive correlation between the child and their adoptive parents implies an environmental effect. A study of over 14,000 adoptions in Denmark found that a significant number of adopted boys with criminal convictions had biological fathers with criminal convictions, demonstrating evidence for a genetic effect.
  • One gene which has been linked to aggression is the gene responsible for the production of protein MAOA which regulates the metabolism of serotonin in the brain, and low levels of serotonin are associated with aggressive behaviour. A study of a Dutch family found that many of its male members behaved in a particularly violent and aggressive manner. These men were found to have abnormally low levels of MAOA, and a defect in this gene was later identified.
  • A second study involving 500 children found that those with low levels of MAOA were more likely to grow up to show antisocial behaviour, but only if they had been maltreated as children. This shows that it is the interaction between genes and the environment that determines behaviours such as aggression.
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Genetic factors in aggression: Evaluation

  • The role of genetic factors on aggression is complex because of more than one gene contributes to a given behaviour, and there may be other factors (e.g. environnmental) that may influence the manifestation of aggressive behaviour. It can be difficult to determine, for example, whether genetic factors determine which environmental factors have an influence, or visa versa, as it is shown in Caspi's study that it is the interaction between genes and the environment that determines behaviours such as aggression, not genetics alone.
  • Most of the studies have measured aggression using self-report techniques or observational studies. Miles found that genetic factors explained a large proportion of the varience in aggressive behaviour in studies that had used parental or self-reports. However, those using observational ratings showed significantly less genetic contribution and a greater influence of environmental factors. This suggests problems with the methodology of many studies: if these studies were valid, one would expect no differences between the results of self-report studies and those of observational studies.
  • Many of the studies in this area have focused on individuals convicted of violent crime. However, these results only represent a small minority of those who are regularly involved in aggressive behaviour, as many violent attacks do not results in a conviction. These individuals may also not be habitual offenders; they may be usually calm people who were designated as violent for a one-time offense. This may explain why so many studies have found little or no evidence of heritability for violence.
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Genetic factors in aggression: Evaluation

  • There is research support for MAOA increasing aggressive behaviour from Cases, who disabled the MAOA gene in mice and found that in these mice, levels of serotonin and dopamine (both of which are associated with higher levels of aggression) increased and aggression increased. This suggests that MAOA reduces aggression by regulating levels of these neurotransmitters.
  • Studies such this one on non-human animals have an important role in helping us understand aggression in humans as it allows us to precisely identify the role of specific genes. However, animals have different genome and physiology to humans, so the effects of genes may be different. The use of animals in studies can also be considered unethical.
  • This research has an important real-world application.  There have been suggestions that if people's genes predispose them towards aggressive behaviour, genetic engineering should be used to change their genes and reduce this risk. Some have even suggested more extreme measures to prevent the heritability of such genes, for example by chemical castration. However the labelling of an individual as dangerous based on their genetic inheritance poses serious ethical questions.
  • Explanations that are purely genetic have been criticised for being too deterministic. They argue that our aggression is pre-programmed, while ignoring the human characteristic of free will. If aggression is purely biologically determined, people cannot be held responsible for their actions; this may have further implications for the legal system when dealing with acts of aggression.
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Evolutionary Explanations of aggression:

  • Wilson claimed that men have evolved strategies to deter their partners from committing adultery, such as vigilance and violence, but are fuelled by sexual jealousy, an adaptation that evolved to deal with the threat of paternal uncertainty.
  • Unlike women, men can never really be sure that they are the fathers of their children, and as a result, men are always at risk of cuckoldry. That a man might invest his resources in offspring that are not his own. The adaptive function of sexual jealousy, therefore, is to deter a mate from infdelity, therefore, minimising risk of cuckoldry.
  • Buss suggested that males have a number of strategies that have evolved specifically to keep a mate which include restricting their partner's autonomy, and violence or threats. As sexual jealousy is a primary cause of violence against women, those who perceived their partners to be threatning infidelity are at more risk of violence. In fact, sudies of battered women have shown that in the majority of cases, women cite extreme jealousy on part of their male partners as the cause.
  • Infidelity is also linked to male violence. Camilleri found that sexual assault of a female by her male partner was directly linked with perceived risk of infidelity.
  • If a child is born, the male risks investing in the offspring of another man, and thus, lowering his own reproductive success. Therefore, when a woman becomes pregnant, the function of violence directed to her may be to terminate the pregancy, thus eliminationg a potential offspring of a rival and leaving her free to bear offspring for him.
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Evolutionary Explanations of aggression: Evaluatio

  • Research has supported the relationship between mate retention strategies and violence. Shackleford found that men who suspected that their wives might be unfaithful gave greater punishments than men who did not. These finding sare consistent with the claim that mate retention strategies are evoked only when a particular adaptive problem is faced, in this case, infidelity.
  • An important applicationof this research is that particular tactics of mate retention can be an early indicator of violence and therefore can potentially be used to alert friends and family members to signs that can lead to future violence. Therefore, help can be sought or offered before the violence ever happens.
  • The claim that male sexual jealousy is linked to aggression is supported by Takahashi who found that using brain imaging techniques, men showed greater activation of the amygdala and hypothalamus (areas associated with aggression), when presented with scenes depicting sexual infidelity in their mate.
  • However, there are claims that our understanding of the relationship between jealousy and aggression is limited. It doesn't tell us for example, whether the perceived infidelity is initiated by the female partner or male rival. Nor does it tell us whether the degree of perceived infidelity is important.
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Evolutionary Explanations of aggression: Evaluatio

  • The link between infedelity and partner violence is supported by the findings that the risk of partner's infidelity predicts violence among men but not females. This is significant because it is the males, not females that are at risk of cuckoldry. Another study suppoting this link found that men convicted of ****** their partners were more likely to have experienced cuckoldry risks prior to their offence.
  • Most of these studies, however, have focused solely on men's mate retention strategies and men's violence against women. However, women also engage in mate retention tactics and sometimes behave violently towards their partners. In fact, research suggests that women carry out physical assaults on their partners as ofetn as men do, and Felson found that women were twice as likely to murder out of jealousy than were men.
  • An evolutionary perspective on violence cannot explain why people react different ways when faced with the same adaptive problem. Shakleford suggested that it could not explain why different males, when faced with their partner's infidelity react in different ways.
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Evolutionary Explan of group display:

  • Waller noted that humans have evolved to live in groups and need to define the boundaries of the behaviour of the group to protect resources such as territory, food and mates from potential threats. Thus, early humans formulated an in group "us" and an out group "them" strategy and this may lead to aggressive behaviour.
  • Suspicion of strangers (xenophobia) increases the propensity for intergroup aggression. MacDonald suggests that it would be adaptive to exaggerate negative stereotypes fo outsiders, as the overperception of threat would be less costly than the underperception. Therefore, group displays of aggressive behaviour is often directed at outsiders, and this may have been favoured by natural selection.
  • Another evolutionary explanation of aggressive behaviour in group display  considers the adaptive benefit of promoting and maintaining cooperation within the group to benefit the members (e.g. food sharing and hunting). Members of a group may show credibility enhancing displays such as painful rituals or fire walking as a way to signal their deep commitment to the group and to be accepted.
  • These are costly signals (e.g. to physical health) and help to solve the adaptive problem of free-riders (those who take advantage but does not contribute). Therefore, natural selection would have favoured the development of violent rituals.
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Evolutionary Explan of group display: evaluation

  • One strength of the evolutionary explanation of group display is that it can explain the behaviour of supporters at sports events. Evans analysed police reports from 40 football matches involving English club sides or the English national side and found more evidence of xenophobia abuse and violence in games involving the English side. This supports the evolutionary explanation that club sides are more ethically diverse and therefore less likely to produce xenophobic responses from foreign supporters.
  • However, Marsh offers an alternative explanation to this. He argues that disempowered young males may achieve social status by taking part in football violence. This suggests it may not be necessary to explain football violence by considering the ultimate mechanisms underlying the behaviour.
  • The evolutionary explanation of group display as being shaped by xenophobia is controversial and socially sensitive. This is because it presents xenophobia and possibly racism as part of the natural behaviour of humans. However, human behaviour is not determined by evolutionary forces, and humans have free will to choose not to behave aggressively towards outsiders due to their highercognitive and moral beliefs. This explanation may offer an excuse for racist behaviour that many would consider to be unacceptable.
  • However, an application is that it does imply that football clubs can try to reduce racism by reducing "in group" identity. For example banning IRA songs by celtic supporters.
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Evolutionary Explan of group display: evaluation

  • The explanation of costly displays to signal commitment is supported by Sosis who found that frequency of warfare was the strongest predictor of the costliness of the society's male ritual displays, as clearly reliable and commited members are necessary during warfare - where costly signalling tended to be permanent displays such as scars. Internal warfare, where group members were more likely to be temporary, is associated with less permanent scars such as body painting. This supports the claim that costly ritualistic displays have evolved to signal commitment.
  • However, these evolutionary explanations for warfare may demonstrate a gender bias as they do not adequately reflect the behaviour of women. Adams claimed that the idea of a woman warrior is almost unheard of in most societies. Women would have considerably less to gain from fighting in certain-death situations and more to lose (e.g. loss of their reproductive capacity). This is fundimental as women simply do not increase their fitness as much as men do. Therefore, our understanding of the displays typically found in warfare is limited to the behaviour of males.
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