An Adaptive Response

Annotations:

• Evolutionary psychologists argue that the different reproductive challenges faced by our ancestors led to a number of evolved sex differences, including sex differences in jealousy.
• Male sexual jealousy is a frequently cited cause of violence in interpersonal relationships.
• In many cultures, the murder of on adulterous wife or her lover is not only condoned but encouraged.
• Among the Nuer people of East Africa, for example, a man caught in adultery runs the risk of death at the hands of the woman's husband.
• As recently as 1974, in the US state of Texas, a man who killed his wife's lover "while in the act," would remain unpunished. 

1. Infidelity and jealousy

   Annotations:

   • Daly and Wilson claim that men have evolved several different strategies to deter their female partners from committing adultery (i.e. infidelity).
   • These range from vigilance to violence, but all are fuelled by male jealousy, an adaptation that evolved specifically to deal with the threat of paternal uncertainty.
   1. Daly and Wilson, 1988
   2. Cuckoldry and sexual jealousy

      Annotations:

      • Unlike women, men can never be entirely certain that they are the fathers of their children, as fertilisation is hidden from them, inside the woman.
      • As a result, men are always at the risk of cuckoldry, the reproductive cost that might be inflicted on a man as a result of his partner's infidelity.
      • The consequence of cuckoldry is that the man might unwittingly invest his resources in offspring that are not his own.
      • The adaptive functions of sexual jealousy, therefore, would have been to deter a mate from sexual infidelity, thereby minimising the risk of cuckoldry.
   3. Mate retention and violence
      1. Buss, 1988

         Annotations:

         • Buss suggests that males have a number of strategies that have evolved specifically for the purpose of keeping a mate.
         • These include "direct guarding" of the female, and "negative inducements" that would prevent her from straying.
         • By restricting their partners' sexual autonomy (direct guarding), our male ancestors would have been able to deter rivals from gaining access to their mates.
         • A modern example of direct guarding is "vigilance", e.g. coming home unexpectedly to see what a female partner is up to.
      2. Wilson et al, 1995

         Annotations:

         • Wilson found that women who agreed with questionnaire items such as "he is jealous and doesn't want you to talk to other men", were twice as likely to have experienced serious violence from their partners, with 72% of these having required medical attention following an assault from their male partner.
         • Men may also attempt to retain their partners by offering threats (i.e. negative inducements for any infidelity.
         • Because sexual jealousy is a primary cause of violence against women, those who are perceived by their partner to be threatening infidelity (e.g. looking at another man), are more at risk of violence than those who are not.
      3. Dobash and Dobash, 1984

         Annotations:

         • Studies of battered women, for example, have shown that in the majority of cases, women cite extreme jealousy on the part of their husbands or boyfriends as the key cause.
   4. Uxoricide (wife-killing)

      Annotations:

      • Men can guard against their partner's infidelity either by conferring benefits or by inflicting costs, including violence.
      1. Shackelford et al, 2000

         Annotations:

         • As not all men possess resources that might be used to provide benefits, some men are especially prone to using violence, or the threat of violence.
         1. Daly and Wilson, 1988

            Annotations:

            • According to Daly and Wilson, death of the partner from physical violence may be an unintended outcome of an evolutionary adaptation that was designed for control rather than death.
      2. Pipat Lueprasitkul

         Annotations:

         • In July 2002, a Thai court freed a man who admitted battering his wife to death in a jealous rage after discovering she had visited a former sweetheart.
         • Pipat Lueprasitkul, a former university lecturer, was given a two-year suspended prison sentence after the court took into account his background and the young age of his children.
         • The court also considered that Pipat attacked his wife Wannee in a fit of jealousy, an explanation that outraged women's groups.
         • According to the World Health Organisation study, nearly half of all women in Thailand are subjected to physical or sexual violence at some point in their lives.
   5. Research support

      Annotations:

      • The predictions concerning mate retention techniques and female-directed violence have been tested in Shackelford's study to the right.
      • This study shows a clear relationship between sexual jealousy, mate-retention strategies by males, and violence towards women.
      1. Buss and Shackelford, 1997

         Annotations:

         • Other research also supports this connection.
         • Buss and Shackelford found that men who suspected that their wives might be unfaithful over the next year exacted greater punishment for a known or suspected infidelity than men who did not anticipate future infidelities.
         • This finding is consistent with the claim in evolutionary psychology that mate retention strategies are evoked only when a particular adaptive problem is faced, in this case the belief that the wife's infidelity is likely.
   6. Practical applications

      Annotations:

      • An important implication of research such as Shackelford's is that particular tactics of mate retention used by males can be an early indicator of violence against the female partner.
      • The findings from these studies can potentially be used to alert friends and family members to the danger signs, the specific acts that can lead to future violence in relationships.
      • At this point, help can be sought or offered before the violence ever happens.
   7. Uxoricide
      1. Shackelford, 2000

         Annotations:

         • Daly and Wilson's explanation of uxoricide, which suggests that most cases are unintended consequences of spousal violence linked to sexual jealousy, is challenged by Shackelford.
         • He analysed half a million homicides, selecting 13,670 where a man had killed his wife. A startling finding was that younger women had a much greater risk of uxoricide regardless of the age of their partner.
         • The fact that men kill their wives when they are most reproductively valuable contradicts evolutionary logic that men should regard such women as "prized property".
         1. Duntley and Buss, 2005

            Annotations:

            • However, an alternative explanation, the "evolved homicide module theory" can explain these findings.
            • A partner's infidelity carries a double loss for the male, particularly when the female is still of reproductive age.
            • Not only does her lose a partner (decreasing his reproductive fitness), but another man gains a partner and increases his own fitness.
            • By killing his wife, he at least prevents a competitor from gaining in the reproductive stakes.
2. Evolution of homicide

   Annotations:

   • Homicide represents the most extreme form of aggression, and statistics worldwide reveal that the majority of the killers and victims are men.
   1. Buss and Shackelford, 1997
   2. Lack of resources

      Annotations:

      • In a study of homicides in Detroit, USA, 43% of the male victims and 41% of the male perpetrators were unemployed despite the fact that only 11% of the adult men in Detroit were unemployed that year.
      • Also, 73% of the male perpetrators and 69% of the male victims were unmarried.
      • A lack of resources and an inability to attract long-term mates appears to lead to increased social competition and male-male homicides.
      1. Wilson and Daly, 1985
   3. Loss of status

      Annotations:

      • One of the key motives of male-male homicide appears to be the defence of status in the local peer group.
      • Because human beings evolved in the context of small groups, a loss of status could have been catastrophic for survival and reproduction.
      • Although maladaptive nowadays, these mechanisms continue to operate, triggered by events that would have triggered them in our ancestral past.
   4. Sexual jealousy

      Annotations:

      • This also appears to be a key motivator of same-sex aggression and homicide, with men predominantly the perpetrators and the victims.
      1. Daly and Wilson, 1988

         Annotations:

         • A summary of eight same-sex killings involving "love triangles" found that 92% were male-male homicides and only 8% were female-female homicides.
   5. Commentary

      Annotations:

      • Because humans face being killed in many different circumstances (e.g. in status contests, by a jealous mate or sexual rival), it is likely that they would have evolved anti-homicide defences, such as being able to read the signs of homicidal intent, and killing in self-defence.
      1. Anit-homicide defenses and the costs of homicide
         1. Duntley and Buss, 2004

            Annotations:

            • Once such mechanisms begin to evolve, homicide becomes a far more costly strategy to pursue.
            • Its success rate becomes lower, and attempting to kill becomes increasingly dangerous for the killer.
            • Both of these consequences mean that homicide gives decreased fitness benefits to the killer.
            • As a response, selection favours the development of deceptive strategies such as concealment of homicidal intent from victims to avoid activating their homicidal defences.
      2. Limitations of the evolutionary perspective on homicide

         Annotations:

         • An evolutionary perspective on aggression cannot explain why people react in such different ways when faced with the same adaptive problem.
         1. Buss and Shackelford, 1997

            Annotations:

            • For example, Buss and Shackelford suggest that, currently, an evolutionary perspective cannot account for why three men confronted with a wife's infidelity will result in a beating in one case, a homicide in the second case, and getting drunk in the third case.
            • Nor can an evolutionary perspective explain why some cultures (e.g. Yanomamo of South America) seem to require male violence to attain status, whereas in other cultures (such as the Kung San of the Kalahari) aggression leads to irreparable reputational damage.
3. Mate retention

   Annotations:

   • Shackelford used a survey method to test evolutionary psychology predictions concerning mate retention strategies.
   • They used 461 men and 560 women in the US. All participants were in committed, heterosexual relationships.
   • Male partners answered questions about their use of mate retention techniques, and were assessed on how often they performed each of 26 different types of violent act against their partners.
   • Female participants answered questions concerning their partners' use of male retention techniques and the degree to which their partners used violence against them.
   • Men's use of two broad types of retention technique (intersexual negative inducements and direct guarding) was positively correlated with their violence scores.
   • In addition, use of emotional manipulation (e.g. saying they would kill themselves if their partner left) as a specific tactic appeared to consistently predict men's violence against women.
   • Results from female participants confirmed this trend, with reports of direct guardings and intersexual negative inducements being positively correlated with their experience of female-directed violence.
   • In addition, women reported that those partners who frequently used specific mate retention tactics of vigilance and emotional manipulation were more likely to use violence against them.
   • As with males, age relationship duration made no difference to the reported trends.
   1. Shackelford et al, 2005
      1. Problems with surveys

         Annotations:

         • In this study, data was collected  using a survey technique.
         • Surveys are a form of self-report technique that have particular problems, especially when used in sensitive areas such as violence against a spouse.
         • Answers may not be truthful because of the social desirability bias - a tendency to respond in a way that will be viewed favourably by others.
         • This takes the form of over-reporting desirable behaviour and under-reporting undesirable behaviour.
4. Gender bias

   Annotations:

   • Most studies of infidelity have focused solely on men's mate retention and men's violence against women.
   • However, women also engage in mate retention tactics and sometimes behave violently towards their partners.
   • Research suggests that women initiate and carry out physical assaults on their partners as often as men do.
   1. Archer, 2000

      Annotations:

      • For example, family conflict studies find approximately equal rates of assaults by women and men,
      • It would be informative, therefore, to investigate whether women's mate retention is also linked to partner-directed violence.

Annotations:

• We have already seen how groups can increase aggressive behaviour through the process of deindividuation, but we now turn our attention to the relationship between group membership and displays of aggression.
• What is there about being in a group that makes people behave in such apparently bizarre ways?

1. US Census Bureau

   Annotations:

   • The US Census Bureau estimates that 4,742 lynchings took place between 1882 and 1968.
   • Many of the victims were accused of little more than "insulting a white man" or "seeking employment out of place".
   • Victims were hanged from trees, often tortured and mutilated before death, burned alive, castrated and dismembered.
   • Not only were lynchings sanctioned by local communities, they were frequently advertised well in advance and tickets sold.
   • People often dressed up for the occasion to enjoy the carnival atmosphere that surrounded these grizzly scenes, with some lynch mobs swelling to as many as 15,000 people.
2. Lynch mobs

   Annotations:

   • In the last decades of the nineteenth century, the lynching of black people in the Southern states of the USA became an institutionalised method used by whites to terrorise blacks and maintain white supremacy.
   1. Social transitions and need for conformity
      1. Myrdal, 1944

         Annotations:

         • Myrdal suggests that the fundamental cause of lynching in the US was fear of the Negro, which led white mobs to turn to "lynch law" as a means of social control.
         • Of the 4,742 documented lynchings, nearly three quarters of the victims were black.
         1. Patterson, 1999

            Annotations:

            • Patterson claims that lynch mobs were more active during this period because it was a time of major social transition (after the collapse of slavery), where the entire community felt at risk.
            1. Ridley, 1997

               Annotations:

               • When groups feel at risk, survival of the group becomes more important, and as Ridley points out, cooperative group defence and antagonism to outsiders go hand in hand.
      2. Commentary
         1. Boyd and Richerson, 1990

            Annotations:

            • Boyd and Richerson provide evidence to support the power of social conformity in group displays of behaviour.
            • They discovered that groups in which cooperation thrived were also those that flourished.
            • This, therefore, provides an explanation of why, when a majority group is more at risk as a consequence of social change, individual self-interest would give way to "groupishness."
   2. Power-threat hypothesis

      Annotations:

      • The racist myth of Negroes' uncontrollable desire to rape white women was frequently used in defence of the lynching practice, although homicides and assault were more frequently cited "threats" to the majority gang.
      1. Blalock, 1967

         Annotations:

         • The threat model of lynch mobs is based on Blalock's power-threat hypothesis which says that groups that pose a threat to the majority are more likely to be discriminated against and to be the subject of violent action.
         • Lynching was an extreme form of discrimination, motivated by perceived racial threat.
      2. Commentary

         Annotations:

         • Part of the difficulty of testing a threat model of the behaviour of lynch mobs is that the nature of social threat is vague and poorly defined.
         1. Clark, 2006

            Annotations:

            • In a study of lynchings in Brazil, Clark concluded that the evidence contradicted the claim that the threat of "dangerous classes" in society was a major causal factor in lynchings.
            • In Sao Paulo, for example, the percentage of Afro-Brazilians in the community was negatively correlated with incidents of lynch-mob violence.
3. Religious rituals

   Annotations:

   • Not all aggressive behaviour is aimed at others, some is self-inflicted as part of an initiation rite or religious ritual.
   • If human beings are rational creatures, why do we indulge in acts that can be painful or at the very least uncomfortable?
   • Among Native Americans, Luiseno initiates were required to lie motionless while being bitten by hordes of ants, and among Shiite Muslims, self-flagellation is still practised as a way of celebrating the holy day of Ashura.
   1. Costly signalling theory
      1. Sosis, 2004

         Annotations:

         • Sosis believes that the inherent costs of religious rituals are the critical feature that contributes to the success of religion, and that natural selection would have favoured their development.
         • By engaging in painful rituals such as self-flagellation, an individual signals commitment to a group and what it stands for.
         • Consequently, religious behaviour can promote cooperation within the group.
         1. Zahavi and Zahavi, 1997

            Annotations:

            • Zahavi and Zahavi suggest that the significant costs of such acts also serve as deterrents for anyone who does not believe in the teachings of a particular group but wants to take advantage of its benefits.
   2. Research support
      1. Sosis and Bressler, 2003

         Annotations:

         • Sosis and Bressler provide evidence to support the claim that the costs of religious commitment contribute to the longevity of religious groups.
         • They found that religious groups tended to impose twice as many costly requirements on their members as did non-religious groups, and the number of costly requirements was positively correlated with the lifespan of the group.
         • This shows us that those religions requiring the greatest displays of commitment (often involving painful rituals) produce the most committed members, and so last the longest.
   3. Costs and benefits

      Annotations:

      • The costly signalling theory predicts that religious rituals are costly to followers in order to deter religious imposters who might otherwise invade religious communities.
      • However, when the pay-offs are high, imposters may still attempt to fake membership of the group.
      • The expectation, therefore, is that the costs surrounding religious rituals should be related to the incentives of membership.
      1. Chen, 2003

         Annotations:

         • This is precisely what was found by Chen, in a study of the Indonesian financial crisis on the 1990s.
         • As the crisis worsened, Muslim Indonesian families devoted a greater proportion of their dwindling financial resources to religious observance.
         • Chen observes that in times of crisis, religious institutions provide social insurance, minimising risk by collectively supporting the most needy.
4. Sports events and xenophobia
   1. Wilson, 1975

      Annotations:

      • Wilson claims that xenophobia has been documented in "...virtually every group of animals displaying higher forms of social organisation."
      • Natural selection, it appears, has favoured those genes that caused human beings to be altruistic toward members of their own group but intolerant toward outsiders.
   2. Shaw and Wong, 1989

      Annotations:

      • Shaw and Wong argue that mechanisms that prompt suspicion towards strangers would have been favoured by natural selection.
      • This would have enabled our ancestors to avoid attack, and so leave behind more offspring.
   3. MacDonald, 1992

      Annotations:

      • MacDonald suggests that from an evolutionary perspective, it is adaptive to exaggerate negative stereotypes about outsiders, as the overperception of threat is less costly than its underperception.
   4. Research support
      1. Foldesi, 1996

         Annotations:

         • Foldesi provides evidence to support the link between xenophobia and violent displays among Hungarian football crowds.
         • He found that the racist conduct of a core of extremist supporters led to an increase of spectators' violence in general, and xenophobic outbursts in particular.
         • Violent incidents based on racist or xenophobic attitudes were observed at all stadia, with gypsies, Jews and Russians the usual targets.
   5. Football violence as a career
      1. Marsh, 1978

         Annotations:

         • Marsh offers an alternative explanation of the aggressive displays of football crowds.
         • He claims that much of what passes for violent behaviour is actually highly ordered and ritualised.
         • Being a football hooligan enables young males to achieve a sense of personal worth and identity in the eyes of their peers.
         • Group displays of aggression, therefore, are not, according to Marsh, an indication of underlying xenophobic tendencies, but part of an alternative "career structure" for working class males.
   6. Xenophobia on the terraces

      Annotations:

      • Podaliri and Balestri illustrate this tendency in their analysis of the behaviour of Italian football crowds.
      • From the end of the 1980s, xenophobic political organisations such as the Northern League in Italy had led to the growth of extreme right-wing movements characterised by racist chants and openly anti-Semitic banners.
      • Nowhere was this more evident than in the curve (terraces) of football stadia in Northern Italy.
      • Chants and banners among the ultras (extremists) of clubs in this region were not only openly xenophobic, but additionally strengthened the cultural identity  of the supporters because they stressed differences between Northern and Southern Italians.
      • A common chant among the ultras of Atalanta Bergamo (a Northern Italian club) was "Bergamo is a nation, all the rest is South."
      1. Podaliri and Balestri, 1998
5. Club or country?

   Annotations:

   • Evans and Rowe analysed data relating to 40 football matches played in 1999/2000.
   • All 40 games were played in continental Europe, and involved both English club sides and the English national side.
   • Post-match reports and interviews with senior police and other officials suggested a much greater degree of disorder associated with games involving the national side than games involving club sides.
   • This was primarily attributed to the influence of nationalism and xenophobia.
   • A possible reason for these findings is that English club sides are more ethnically diverse than the national side, and so less likely to invoke xenophobic responses from foreign supporters.
   1. Evans and Rowe, 2002
6. Lynch mobs and deindividuation
   1. Mullen, 1986

      Annotations:

      • Mullen carried out an archival analysis to determine whether the atrocities committed by lynch mobs could be accounted for in terms of self-attention processes.
      • He coded 60 newspaper reports of lynching events for information regarding group composition and the level of atrocity (e.g. the occurrence or non-occurrence of hanging, shooting, dismembering of the victim, etc.).
      • It was found that, as the lynch mob grew in size, the lynchers became less self-attentive, or more deindividuated.
      • This led to a breakdown in normal self-regulation processes, which in turn led to an increase in the level of atrocities committed against the victim.
7. Evolutionary approach

   Annotations:

   • An analysis of the adaptive advantages of religious ritual and commitment to religious practices helps us to understand the success of religion from a purely evolutionary perspective.
   • However, there is also a dark side to this understanding.
   • If the intragroup solidarity that religion promotes is its significant adaptive advantage, then its disadvantage for a peaceful world must be its role in intergroup conflict.
   1. Sosis, 2000

      Annotations:

      • Sosis points out that one of the benefits of intragroup solidarity is the ability of unified groups to defend and compete against other groups.
      1. Roes and Raymond, 2003

         Annotations:

         • Ross and Raymond found that societies with stricter religious practices tend to have higher levels of intergroup conflict.
         • They argued that societies only attained a large size if they were bound together by a religiously inspired morality, reducing internal conflict and promoting group cooperation in the face of external enemies.
8. Application to real-world

   Annotations:

   • The power of xenophobia to invoke violence has motivated football clubs to take steps to minimise its influence.
   • In Germany, in December 1992, all the teams in the Bundersleague played in shirts displaying the slogan, "Mein Freund ist Auslander" (My Friend is a Foreigner).
   • In Scotland, a century of sectarian bigotry has been addressed by the two Glasgow teams.
   • Celtic have introduced the "Bhoys against bigotry" campaign and Rangers have finally abandoned their long-standing tradition against the signing of Catholic players.
   • In England, initiatives such as Sheffield United's "Football Unites, Racism Divides" have attempted to forge stronger links with local ethnic communities.
   1. Bradbury, 2001

      Annotations:

      • In an audit of clubs' policies of racism, Bradbury concluded that although progress has been made, much more needs to be done, including taking direct action against racist and xenophobic incidents.