experiments in group conflict

November 1, 1956

Experiments in Group Conflict

What are the conditions which lead to harmony or friction between groups of people? Here the question is approached by means of controlled situations in a boys' summer camp

By Muzafer Sherif

• DOI: 10.1038/SCIENTIFICAMERICAN1156-54
• Corpus ID: 4209660

Experiments in Group Conflict

• Published in Nature 1 November 1956

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Robbers Cave Experiment | Realistic Conflict Theory

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The Robbers Cave experiment, conducted by Muzafer Sherif in the 1950s, studied intergroup conflict and cooperation among 22 boys in Oklahoma. Initially separated into two groups, they developed group identities. Introducing competitive tasks led to hostility between groups. Later, cooperative tasks reduced this conflict, highlighting the role of shared goals in resolving group tensions.

The hypotheses tested were:

• When individuals who don’t know each other are brought together to interact in group activities to achieve common goals, they produce a group structure with hierarchical statuses and roles.
• Once formed, two in-groups are brought into a functional relationship under conditions of competition, and group frustration, attitudes, and appropriate hostile actions about the out-group and its members will arise; these will be standardized and shared in varying degrees by group members.

Study Procedure

Phase 1: in-group formation (5-6 days).

The members of each group got to know one other, social norms developed, leadership and group structure emerged.

Phase 2: Group Conflict (4-5 Days)

The now-formed groups came into contact with each other, competing in games and challenges, and competing for control of territory.

Phase 3: Conflict Resolution (6-7 Days)

Sherif and colleagues tried various means of reducing the animosity and low-level violence between the groups.

The Drinking Water Problem

The problem of securing a movie, realistic conflict theory.

Realistic conflict theory posits intergroup hostility and conflict arise when groups compete for limited resources. It emphasizes that competition over scarce resources (material goods, power, or social status) can lead to prejudice, discrimination, and animosity between groups.

• Resource Scarcity and Competition : When groups perceive that they compete for limited resources, hostility can arise.
• Formation of Ingroup and Outgroup Dynamics : Through competition, groups develop a strong sense of “us” (ingroup) versus “them” (outgroup). This distinction can lead to negative stereotyping and increased animosity.
• Superordinate Goals : Intergroup hostility can be reduced when conflicting groups collaborate on goals that neither group can achieve on its own. These goals supersede their smaller individual goals and encourage cooperation.

Critical Evaluation

Key takeaways.

• In the Robbers Cave field experiment, 22 white, 11-year-old boys were sent to a special remote summer camp in Oklahoma, Robbers Cave State Park.
• The boys developed an attachment to their groups throughout the first week of the camp by doing various activities together, like hiking, swimming, etc.
• The boys chose names for their groups, The Eagles and The Rattlers.
• During a four-day series of competitions between the groups prejudice began to become apparent between the two groups (both physical and verbal).
• During the subsequent two-day cooling-off period, the boys listed features of the two groups. The boys tended to characterize their own in-group in very favourable terms, and the other out-group in very unfavorable terms.
• Sherif then attempted to reduce the prejudice, or inter-group conflict, shown by each group. However, simply increasing the contact of the two groups only made the situation worse.
• Alternatively forcing the groups to work together to reach common goals, eased prejudice and tension among the groups.
• This experiment confirmed Sherif’s realistic conflict theory (also called realistic group conflict theory), the idea that group conflict can result from competition over resources.

Further Information

• Allport’s Intergroup Contact Hypothesis: Its History and Influence
• Aslam, Alex. “War and Peace and Summer Camp.” Nature, vol. 556, 17 Apr. 2018, pp. 306-307.

The Robber’s Cave

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• M. Sherif  

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Psychology has offered two basic approaches to describe the phenomenon of prejudice. One line of argument sees it as an individual problem; a sick person model of prejudice. The major influence here is psycho-analysis and the work of Freud, with the root of prejudice being seen to be in childhood experiences that create a damaged adult personality. Adorno et al. (1950) presented the picture of the authoritarian personality who projects his or her unresolved childhood conflicts onto minority groups. The authoritarian personality is narrow minded, a stickler for rules, inhibited about sex, unquestioningly submissive to authority, intolerant of ambiguity, and politically conservative. The basic flaw in this approach to prejudice is the insistence that prejudice is a sign of a sick personality, and that, by implication, most people are not prejudiced.

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Prejudice: Intra- and Interpersonal Aspects

Modern Prejudice

Gordon Willard Allport: The Nature of Prejudice, Addison-Wesley: Reading, MA 1954, 537 S. (dt. Die Natur des Vorurteils, Kiepenheuer & Witsch: Köln 1971, 531 S.)

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© 1996 Philip Banyard and Andrew Grayson

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Sherif, M. (1996). The Robber’s Cave. In: Introducing Psychological Research. Palgrave, London. https://doi.org/10.1007/978-1-349-24483-6_9

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Anger, legacies of violence, and group conflict: An experiment in post-riot Acre, Israel

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GROUP CONFLICT: Experiment in Group Conflict by Sherif

“Conflict between groups – whether between boys’ gangs, social classes, “races” or nations – has no simple cause, nor is mankind yet in sight of a cure” (Sherif 1956)

Behavioral Science: A Quick Background Story

The studies of group conflict belong to Behavioral science, which is a new, yet, at the same time, an old science. The roots of behavioral science go back to socio-biology, with Charles Darwin as a pioneer, and have evolved through evolutionary-, cognitive- and social psychology. After World War 2, behavioral science and especially social psychology became popular mainly in the United States. The research questions were motivated by a concern to avoid a new World War and Holocaust in a combination with a curiosity as to what triggers group-conflict and obedience to authority.

In this paper, we focus on the classic field experiment by the authors Sherif and Sherif; commonly referred to as the Robbers Cave Experiment. Sherif’s research questions look into particular to questions:

• What sparks group conflicts?
• How can we bring harmony between groups?

The experiment was conducted in Robbers Cave State Park, Oklahoma. The study, which is called Experiment in Group Conflict, was first published in the journal Scientific American in 1956 (vol. 195, no 5). Further elaborations of the study were published in 1958 and 1961.

The experiment is a classic in Behavioral science as it demonstrates how social dynamics work to establish groups and how group conflicts , prejudices, and stereotypes can escalate and get out of hand.

Modern Behavioral Science

Today’s Behavioral science is well-known for its contribution to the social sciences. Empirical studies show that the human cognition (thinking) is not a mainly rational process as once believed. Especially, Nobel Prize-winner D. Kahnemann has formed a new scientific agenda focusing on cognitive biases, habits, and intuitions as central in our decision-making.

Rationality does play a part in our decision-making but it is a slow and energy-demanding process, so unless we get a clue where rationality is in demand we try to avoid the use of it. This renders our decision-making open to biases such as, for example, preferring people in our own group; also called in-group favoritism .

The Robbers Cave State Park Experiment

The social experiments took place in the Robbers Cave State Park, Oklahoma in 1954. Twenty-two 11-12-year-old boys were sent summer camping in Robbers Cave.

During the first phase of the experiment, the boys were assigned to one of two groups. Hereafter, the two groups were kept apart. The group members participated in different tasks and duties such as cooking and hiking. The social life in the groups, especially solving tasks, led to the formation of coherent groups with social hierarchies in which leaders (alpha), beta (followers), and at least one omega as an underdog emerged.

The boys chose names for their groups, The Eagles and The Rattlers, and painted them onto shirts and flags.

In the second phase of the experiment, groups start interacting with each other. Further, the research team arranged competitions in order to produce friction between the groups of boys. They arranged tournaments of games: baseball, treasure hunt, football, and so on. The tournaments started out as good sportsmanship but ended in dirty rivaling.

The rivaling got worse; it escalated and intensified. At first, this prejudice was only verbally expressed, such as teasing, taunting, or name-calling. As the competitions wore on, this expression took a more direct route. The Eagles burned the Rattler’s flag. The next day, the Rattler’s ransacked The Eagle’s cabin, overturned beds, and stole private property.

Within each group, solidarity increased in combination with changes in social hierarchies. One leader was removed because he could not stand the pressure, and a boy who previously was regarded as a bully (omega) was made a hero due to his bullying of members of the other group.

Finally, the groups became so aggressive with each other that the researchers separated them and progressed into a third phase of the experiment. The aim of this phase was to examine how the groups could be brought together in harmony.

At first, the two groups were brought to social events such as going to the movies, eating in the same dining room, and so on. Unfortunately, this was counterproductive as the social events served as opportunities for the rival groups to attack each other again and thereby intensify the conflict.

Sherif describes how favorable information about the other group was reinterpreted to fit stereotyped views about the group. Furthermore, leaders could not act without regard for the prevailing temper in the groups.

Due to the failed attempt to bring harmony to the inter-group relations, the research team changed strategy. They brought the groups together to work on common ends that could only be achieved if the two groups worked together.

The groups had to work together to secure the water supply and gain access to food.

These joint efforts did not immediately dispel hostility, but gradually the series of cooperative acts reduced friction and conflict. Gradually new friendships developed between individuals in the two groups. In the end, the two groups decide to hold a joint campfire.

Sherif (p. 58) formulates it like this:

“ In short, hostility gives way when groups pull together to achieve overriding goals which are real and compelling to all concerned”

The Relevance of the Experiment Today?

The Robbers Cave study has been criticized for a number of reasons. First, the sampling in the study is obviously a problem as the study only includes white healthy middle class 11-12 years old boys from stable protestant homes. Girls, other races, and other religious beliefs than Protestantism were not included.

Further, the study is criticized for being unethical. The participants were deceived, as they did not know the true aim of the study. Also, participants were not protected from physical and psychological harm.

Can we learn from the experiment? Yes, we can learn that it takes very little perceived competition to accelerate group conflicts. At the same time, the question is whether or not we convince ourselves that we are neutral in our own decisions or realize that we do have a tendency to favor people from our own group in everyday life, working life, and the organization that we work in?

We all interact with each other in many different group formations and make important decisions. But do we actually value the suggestions from people who are not in our group when they have better suggestions or more relevant information, or do we prefer suggestions from our own group members?

Furthermore, when groups are established it is not easy to change group members’ perception of themselves and the outgroup. The way out of inter-group conflicts with a spin of prejudice and stereotypes is to establish a common goal that can make individuals from different groups work together.

The Robbers Cave experiment illuminates the kind of group conflicts that take place all over the world. The conflicts are salient in civil wars with ethnic cleansing and wars between nations, but inter-group conflict and bringing harmony between individuals with a commitment to groups are relevant far beyond war issues.

Competition arises in situations where people perceive resources to be scarce, and that is a trigger of group conflict, especially if the distribution of resources is regarded as unfair. There is a lot of evidence that when people compete for scarce resources (e.g. fundamental rights, jobs, land, etc.) there is a rise in hostility between groups. For example, in times of financial difficulty, there may be high levels of racism among white people who believe that black people take their jobs, and asylum seekers are profiting off a well-established welfare system. These are among the more contemporary and challenging examples of accelerating group conflicts today.

From a historical perspective, we find prominent examples of group conflict, e.g. the US Civil War, The French Revolution, the fight against apartheid, and the women’s movement. These examples illuminate how group conflict has the potential to change a system. The group conflict in these cases is in defining fundamental rights and thereby defining who is part of the common in society.

In light of this experiment, an enormously important task of a leader is to keep people on the same page working together with a common purpose.

Use the knowledge about behavior and expect perspectives to be influenced by group dynamics. Be aware of the different roles each coworker has in the group. If you’re working with reorganizing, and especially the merging of organizations, pay attention to inter-group conflicts, particularly the ‘Us Versus Them’ perspectives that will flourish. Even though there won’t be fights over food there will by fights for identities and common goods and resources in the organization.

Sherif, M. (1954). Experimental study of positive and negative intergroup attitudes between experimentally produced groups: robbers cave study.

Sherif M. (1956). Experiments in Group Conflict. Scientific America, v195 nr. 5, pp 54-59.

Sherif, M. (1958). Superordinate goals in the reduction of intergroup conflict. American Journal of Sociology, 349-356.

Sherif, M., Harvey, O. J., White, B. J., Hood, W. R., & Sherif, C. W. (1961). Intergroup conflict and cooperation: The Robbers Cave experiment (Vol. 10). Norman, OK: University Book Exchange.

Please note that we write Sherif and Sherif even though the first article only has Muzafer Sherif as the author. Muzafer’s wife was deeply involved in the project but she only appears as an author in the last article from 1961. Sherif and Sherif have later explained that the project was a collaboration.     

About the Authors:

Pia vedel ankersen.

Pia Vedel Ankersen , PhD, is Director of the Research Program Organization, Coordination, and Citizen Involvement at the VIA Campus Research Center for Management, Organization, and Social Science.

Pernille Bjørnholt Nielsen

Pernille Bjørnholt Nielsen , cand.scient.soc, is a consultant at DEFACTUM – a research and consultancy house. She is also the managing director at TegnLet – a Danish company helping organizations use drawings to enhance communication in processes of design, planning, and change processes, etc. – combining behavioral science with graphic facilitation.

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1 Understanding and Responding to Intergroup Conflict: Toward an Integrated Analysis

Linda R. Tropp, Department of Psychological and Brain Sciences, University of Massachusetts Amherst, MA, USA

• Published: 21 November 2012
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Conflicts based in ethnic, religious, and racial differences continue to erupt around the world, despite decades of intervention and scholarly research. It is difficult to assess precisely what contribution social science has made to an adequate diagnosis of the sources of violent conflict. Harder still to know is how best to move forward to alleviate conflict, promote reconciliation, and achieve sustainable, peaceful relations among diverse groups. A primary goal of the present volume is to bring together social psychological and peace perspectives, and to encourage a more integrative approach to the study of intergroup conflict and peace as we look toward the future.

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Cooperation and conflict: field experiments in Northern Ireland

Antonio S. Silva

http://orcid.org/0000-0002-7029-1048

[email protected]

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The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group's success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters' returns) with two religious groups with an on-going history of conflict—Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion.

1. Introduction

The notion of parochial altruism chimes with our folk belief that group members pull together in times of adversity; for example, during the second World War, the term Dunkirk spirit came into common use following the evacuation of Allied troops across the English Channel aided by civilians, at a great risk to themselves, using flotillas of pleasure boats and working barges at the Battle of Dunkirk in 1940 [ 1 ]. Recently this idea has been formalized through a series of mathematical models in which intergroup conflict plays a prominent role in the evolution of cooperation. Models of multi-level selection depend on competition between groups over access to resources (such as food, mates or territory) for cultural or genetic traits that harm the individual and favour the group, such as altruism, to be selected [ 2 – 4 ]. In situations of intergroup conflict, it is argued that the combination of in-group altruism and out-group hostility—in what is termed parochial altruism—provides a selective advantage to groups, resulting in the coevolution of parochial altruism and intergroup conflict by group extinction through conquest and assimilation.

Studies in the laboratory and the field have shown an association between cooperative behaviour and intergroup conflict [ 5 – 10 ]. While it should be noted that this type of cooperative behaviour is not necessarily associated with altruism sensu stricto (i.e. lifetime fitness costs to the actor), as described in the models of parochial altruism [ 2 – 4 ], the findings from these studies are normally put forward as supporting empirical evidence [ 6 – 10 ]; a study in Burundi found that individuals who suffered the most during the conflict between Hutus and Tutsis were more likely to donate to an anonymous member of their community in a version of a dictator game [ 7 ], teenagers (but not children and adults) in Georgia and Sierra Leone were more egalitarian in a sharing game to in-group than to out-group members [ 9 ], and senior citizens in Israel were more likely to reject an unfair offer in an ultimatum game during the Israel–Hezbollah war when compared with before and after the war [ 8 ].

However, these studies are hindered by methodological limitations that reduce their explanatory power of real-world evolutionary dynamics. First, the majority do not distinguish between different types of cooperative behaviour, conflating in-group with unbiased cooperation (i.e. cooperation with a neutral group), and also failing to measure out-group cooperation (i.e. cooperation with a rival group) [ 7 , 8 , 10 ]. Yet, the accurate identification of the specific type of cooperative behaviour is crucial in the models of the evolution of cooperation through intergroup conflict, as a group benefit is only obtained if cooperation is aimed towards the in-group and not indiscriminately applied [ 11 ]. Second, the experimental set-up of these studies [ 5 – 10 ], while sometimes based in a setting of conflict, never consists of games played between individuals from both groups that are in actual conflict, instead using children from different schools [ 9 ], anonymous neighbours who may or may not have shared group membership [ 7 ] or senior citizens from the same ethnic group [ 8 ]. Experiments using these types of abstract group categorization may not reflect the true dynamics of intergroup competition and prompt the subjects to play according to other real-life cooperative social norms that are not relevant to the hypotheses being tested [ 12 – 15 ]; for example, the Orma of Kenya are more likely to contribute to a public good game, as the game is similar to an existing structure of social contribution, the harambee [ 15 , 16 ]. Thus, other groups with lower average contributions are not necessarily less cooperative; it may just be that the games invoke no real-life norm for those groups. Finally, there is evidence of a lack of consistency between different game-based measures of cooperation within the same individuals and populations [ 12 ], alongside concerns that players in some traditional economic games may not fully comprehend the pay-off structure involved [ 17 , 18 ].

In our study, we address these issues by establishing an experimental set-up based on real-world institutions and cultural groups, and the use of novel naturalistic experimental methods, school/charity donations and lost letters. Our experimental design aims to capture the context-dependent nature of cooperation by measuring cooperative behaviour in a real-world setting, with the lost letter experiment indicating a time commitment to find a post-box and the donation experiment associated with a monetary cost and benefit. In particular, the use of donations to primary schools in our experiments intends to reflect actual intergroup grievances in Northern Ireland associated with school funding [ 19 ]. The individuals in our study are not aware that the donations or lost letters were part of an experiment, therefore minimizing the artificiality typical of most laboratory and field-based economic games.

We measure cooperative behaviour using two groups with a long and ongoing history of conflict: Catholics and Protestants in Belfast, Northern Ireland. This conflict dates back to the seventeenth century, but a renewed bout of violence erupted in the 1960s resulting in over 3000 people killed and tens of thousands injured [ 20 ]. The intensity of the conflict has eased since the Good Friday Agreement in 1998, but in 2011 alone over 130 sectarian bombings and shootings were recorded [ 21 ]. The levels of residential, marital and educational segregation between the two groups are striking; the large majority of the population still live in segregated neighbourhoods (sometimes separated by separation walls); 94% of children attend segregated schools [ 21 ] and only 12% of marriages are between people of a different religion [ 22 ]. These two endogamous communities thus have high levels of segregation, a history of violent conflict and clearly defined group boundaries and institutions, making them a highly relevant population in which to test hypotheses related to the evolution and maintenance of cooperation through intergroup conflict.

We ran two large-scale experiments—school donations and lost letter experiments—to measure biased (towards the in-group or out-group) and unbiased cooperative behaviour across different Belfast neighbourhoods representing a wide range of socio-economic characteristics.

Figure 1. Sample of 22 neighbourhoods in Belfast, UK where the surveys and lost letters experiment were conducted. See the electronic supplementary material, figure S2 for subsample of neighbourhoods where the donations experiment was conducted.

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From this survey sample, we randomly allocated a subsample of 466 individuals in 16 neighbourhoods (electronic supplementary material, figure S2) to take part in the donation experiment that was conducted immediately after the completion of the questionnaire. The subsample random allocation was determined by performing the donation experiment at two out every three houses visited in the neighbourhood. Individuals in this subsample were offered the possibility of donating part or all of the money to the local Catholic or Protestant primary school or a neutral charity unaffiliated with any religious group, Save the Children . Individuals were only offered the option to donate to a single institution, which was randomly allocated.

Second, we ran a lost letter experiment [ 23 ] for which we dropped 832 stamped letters in the same 22 neighbourhoods where the survey was conducted in two rounds in May and June 2012 ( n = 624) and 2013 ( n = 208). These stamped letters were addressed to either fictional sectarian or neutral charities ( CatholicAID , ProtestantAID and CancerAID ; electronic supplementary material, figure S4) and were dropped by two researchers on the pavement with the address facing up on rain-free days. To avoid a return bias dependent on the day and time that the letters were dropped (e.g. when the postman or street cleaners come), each neighbourhood was visited three times at three different time slots (morning, lunchtime and afternoon) on three different days, which were randomly selected (see the electronic supplementary material for more details).

The school donation is a natural experiment that has essentially the same pay-off structure as a dictator game [ 24 ], albeit one that is administered surreptitiously and involves real-life cooperative behaviour involving an institution. We are then able to measure the level of cooperation towards a neutral institution (donating to Save the Children), an in-group institution (e.g. Catholic individual donating to a Catholic school) and an out-group institution (e.g. Catholic individual donating to a Protestant school). The lost letter experiment provides an additional measure of cooperative behaviour; we measured unbiased cooperation by the return rate of letters addressed to CancerAID and biased cooperation by the return rate of letters addressed to CatholicAID and ProtestantAID in predominantly Protestant and Catholic neighbourhoods (more than 75% composition of one group), measuring in-group cooperation when the letter is addressed to an organization representing the neighbourhood's majority group and out-group cooperation when the letter is addressed to an organization representing the neighbourhood's minority group.

We test two main hypotheses derived from the theoretical models of intergroup conflict and parochial altruism [ 2 – 4 ]. First, we predict increased exposure to intergroup conflict will be associated with both increased in-group cooperation and decreased out-group cooperation (i.e. parochial altruism), at both the individual and neighbourhood level. Second, we predict intergroup conflict will better explain the variation in in-group cooperation than unbiased cooperation. To test these hypotheses we use multi-level logistic regressions with the binary response variable of donation or no donation and a logistic regression with the binary response variable of the return or not of a lost letter. We ran one regression for overall donations and one for lost letters' overall returns, plus three separate ones by treatment type. The main explanatory variables of interest are the individual level of sectarian threat for the donation analyses and the neighbourhood aggregate level of sectarian threat for the lost letters analyses, and the interactions between these threat variables and the three different treatments (neutral, in-group and out-group). In the donation analyses, we controlled for individual age, gender, educational level household income, religion, having children and neighbourhood level of religious heterogeneity; for the lost letter analyses, we controlled for religious composition, aggregate household income, number of post-boxes, population density and level of religious heterogeneity at the neighbourhood level (see the electronic supplementary material for more detail). The multi-level structure of the analysis allows us to control for the non-independence of individuals' behaviour clustered at the neighbourhood level [ 25 ].

Figure 2. Donations by individual threat index. Predicted probability of an individual donating to an in-group, out-group and neutral institution by the level of individual threat index. This measure is a continuous factor composed of the variables related to the individual exposure to sectarian attacks and threat (details are provided in the electronic supplementary material). This effect is controlled for individual age, gender, educational level, household income, religion, having children and neighbourhood level of religious heterogeneity. Error bars represent the standard errors. (Online version in colour.)

Figure 3. Letters returned by neighbourhood threat index. Predicted probability of return of in-group, out-group and neutral lost letters by the level of neighbourhood threat index. This measure is the neighbourhood aggregate of the continuous factors, which are composed of the variables related to the individual exposure to sectarian attacks and threat (details are provided in the electronic supplementary material). This effect is controlled for neighbourhood religious composition, income deprivation, number of post-boxes, population density and level of religious heterogeneity. Error bars represent the standard errors. (Online version in colour.)

In contrast, we found that SES best explained the variation in overall cooperative behaviour. At the mean values for all other traits, individuals in the highest income group were 25% more likely to donate than individuals in the lowest income group ( table 2 ) and letters dropped in least deprived neighbourhoods had a 72% probability of being returned compared with 48% in the most deprived neighbourhoods ( table 3 ). In relation to education, individuals with a university degree had an 80% probability of donating compared with 60% for individuals with only primary schooling ( table 1 ). When looking at the specific types of cooperative behaviour, we found wealthy people and wealthy neighbourhoods associated with more help to the in-group and higher-educated people more likely to donate to the out-group and to Save the Children ( tables 2 and 3 ). We also found that people with children were more likely to donate, but specifically to in-group not out-group schools ( table 2 ).

4. Discussion

Our results indicate that while in a situation of intergroup conflict, individuals are more likely to reduce cooperation with out-group members, this will have no effect on cooperative behaviour towards the in-group. Current theoretical models of parochial altruism build on the assumption that increased pro-sociality or in-group altruism results in a group advantage in a situation of intergroup conflict [ 2 – 4 ]. Laboratory-based empirical results supporting these models are based on a game pay-off structure in which altruistic groups always outcompete selfish groups in a situation of group conflict [ 5 , 10 ]. Here, we question whether this assumption is realistic and argue that it is not generalizable to all situations where groups are in competition or conflict. In the case of Catholics and Protestants in Northern Ireland recent conflict between the two groups has mostly been over issues related to schools, housing and symbolic displays [ 21 ]; it is possible that in these situations increased group cohesion does not provide a group advantage, or that the individual cost of helping the group outweighs the potential group advantage.

In situations of intergroup conflict where within-group cooperation may provide a group advantage—such as intergroup warfare—the individual bearing the costs for the group may not be acting out of altruistic concerns. Instead the behaviour may be the result of reputation considerations [ 26 ], enforcement by other group members or the prospect of personal material gain [ 27 ], or may represent hierarchical dominance structures (e.g. conscription) in larger societies which may operate for the benefit of powerful individuals [ 28 ].

Our results point to the importance of SES in explaining the variation in cooperative behaviour as found in previous studies [ 29 , 30 ], and put in question the findings of previous studies on intergroup conflict and cooperation that fail to take into account the variation of individual SES [ 5 , 6 , 8 – 10 ]. The lower levels of cooperation found for individuals of low SES in behaviours where there is a monetary stake, such as the donations experiment, could be explained by the relative cost of cooperation being higher for poor individuals than for wealthy ones. The fact that we also find individuals in deprived neighbourhoods less likely to engage in an cooperative act without an associated monetary cost (i.e. posting a letter) is more surprising, but the harsh environment and possible shorter-time horizons of individuals experiencing income deprivation [ 31 ] may minimize the potential for long-term reciprocity leading to a general reduction in cooperative behaviour [ 32 ]. Notably, low-income individuals in our sample are less likely to trust people in their neighbourhoods lends support to this proximate explanation (see the electronic supplementary material).

Another possibility, proposed by Gavrilets & Fortunato [ 33 ], is that within-group inequality is driving the differential investment in the between-group conflict, with the different individual costs and benefits of intergroup conflict resulting in higher in-group contributions by high-status individuals. In other words, in a situation of intergroup conflict, high status individuals have more to gain or lose, and as a result, are more likely to invest in the in-group. According to this model, the behaviour of high-status individuals is seemingly altruistic at the within-group level, however, these individuals' behaviour is not motivated by altruism but rather by competition with their high ranking peers in other groups. Our results provide some empirical support for this model as we find that both wealthy individuals and neighbourhoods are more likely to contribute to the in-group, possibly indicating that wealthy Catholics and Protestant are more willing to invest in intergroup competition.

The fact that individuals with children were more likely to donate to an in-group, but not an out-group school, led us initially to assume that people wanted to benefit their own children's school. However, when re-analysing the data using instead the binary variable of children currently living at home (more likely to reflect children attending the nearby in-group school, than offspring who may have left the household) no significant effect was found (see the electronic supplementary material, table S6). This suggests that shared kinship is not the mediating mechanism for increased donations. People with children are also more likely to donate to the neutral charity Save the Children, but this might be related to a priming effect of people with children being more inclined to donate to a charity invoking children. It is also interesting to note that levels of neighbourhood religious heterogeneity do not affect cooperation, challenging the notion that group diversity undermines social cohesion [ 34 ].

There are some potential limitations to our study. It is possible that our neutral institutions were, in fact, perceived as biased towards one or other religious group, but neither religious background or threat levels significantly explain the variation in neutral donations or letters return. This suggests that neutral institutions are not particularly affiliated with either group. The donation experiment induces a possible priming effect on the participants, as it was conducted after the questionnaire. We decided against conducting the experiment before, as this might have raised suspicion from the participants that they were taking part in an experiment. We would expect a prime to amplify the effects of conflict on parochial altruism (i.e. increase in-group altruism and reduce out-group altruism), so the reduction in out-group cooperation might be less striking without priming. However, the prime should also enhance in-group cooperation if parochial altruism is operating, and as exposure to conflict in our primed experiment did not predict variation in in-group cooperation, the effect is not likely to be present without the prime either.

Our experimental design also does not allow us to resolve endogeneity issues, as the levels of exposure to violence may not be exogenous to individual cooperative behaviour; for example, younger, poorer and less-educated individuals may be more likely to be involved in sectarian conflict and as a result feel more threatened. In order to attenuate these endogeneity issues we control in our analysis for the contextual variables significantly correlated with intergroup conflict. Furthermore, we should be aware of the selection bias inherent to studies involving active participation, such as our donations experiment, as people willing to participate in the survey could be more cooperative than the wider population (i.e. participating in the study in itself may be a cooperative act) [ 13 ]. Nevertheless, we find our sample to be representative of the population at the neighbourhood, city and country level when comparing it with the 2011 UK Census data on of gender, religion, age, education and employment status (see the electronic supplementary material, table S3).

Finally, the lost letter experiment—which does not suffer from selection bias—largely replicates the donations' results, with both pointing to the importance of SES and how conflict negatively affects cooperative behaviour towards the out-group. Our results highlight the importance of empirically testing theoretical models by measuring large-scale cooperation in a real-world setting, and demonstrate how adversity, either from conflict or deprivation, leads to the breakdown of all types of cooperation.

Acknowledgements

We thank Leo Dunstan, Emily Borrelli, Rahmat Tarsat and Adam Kenny for their help with the data collection and Alexandra Alvergne, David Lawson, Shakti Lamba, Caroline Uggla and the members of the Human Evolutionary Ecology Group at University College London for their feedback.

Data accessibility

The dataset with survey, donations and lost letter returns information is available from Dryad, doi: dx.doi.org/10.5061/dryad.g722q .

Funding statement

The research was supported by the Fundação para a Ciência e a Tecnologia, Portugal and a European Research Council Advanced Award to Ruth Mace ( ERC AdG249347 ). This study was approved by the UCL Research Ethics Committee (ID: 2390/002).

© 2014 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ , which permits unrestricted use, provided the original author and source are credited.

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• DOI: https://doi.org/10.1098/rspb.2014.1435
• PubMed: 25143042
• Published by: Royal Society
• Online ISSN: 1471-2954
• Manuscript received 11/06/2014
• Manuscript accepted 28/07/2014
• Published online 07/10/2014
• Published in print 07/10/2014

• evolution of cooperation
• parochial altruism
• intergroup conflict
• real-world measure

Large datasets are available through Proceedings B 's partnership with Dryad

Experiments in Group Conflict

• Sherif, Muzafer

Robbers Cave Experiment

Life imitates art, and art imitates life. Many say, for example, that the Robbers Cave Experiment and  Lord of the Flies  are an example of art imitating life.

Did you read Lord of the Flies in middle school or high school? Even if you skimmed over the book, you might remember what it’s about. A group of boys finds themselves stranded on a desert island without adult supervision. As they try to establish a society, they turn on each other in desperation, and things get brutal.

The book has become a staple of Young Adult fiction and is known for being a reflection of society. It warns that anyone has the potential to get violent if they are desperate enough for scarce resources.

Lord of the Flies came out in 1954. The year before, the Rockefeller Foundation gave psychologist Muzafer Sherif $38,000 to conduct a fascinating research experiment. Tired of working with lab rats, Sherif set out to do something unusual - an experiment that one could say mirrored Lord of the Flies.  He ended up putting together the Robbers Cave Experiment.

What Is the Robbers Cave Experiment?

The Robbers Cave experiment, once known for its fascinating insight into group conflict theory, is now more infamous than famous. Regardless of its reputation, it remains one of the most well-known social psychology experiments of the 20th century. It attempted to reveal fascinating insights into group conflict and how easily people turn against each other. 

Who is Muzafer Sherif?

Muzafer Sherif is the man behind the Robber’s Cave Experiment. Born in Turkey, he witnesses a lot of violence due to the separation of ethnic groups. The violence encouraged him to become a psychologist and attend Harvard University. When he originally published the Robbers Cave Experiment, he earned praise for his work. In recent years, however, criticisms of the Robbers Cave experiment have overshadowed his accomplishments.

How the Robbers Cave Experiment Was Conducted

Sherif’s theory.

Sherif wanted to show how easily groups could turn on each other when they were fighting for limited resources. But he also wanted to show how easily those groups could set aside their differences and come together to defeat a common enemy. Observing these group dynamics couldn’t be done in a lab with rats or dogs. So he took his experiments to a summer camp.

The 22 boys at Robber’s Cave State Park did not know that their summer camp experience would be part of a larger social experiment. They didn’t even know how many people would be at the camp until the second day. On the first day, researchers posing as counselors established two groups of campers: The Eagles and the Rattlers. After the boys bonded within their groups, they were introduced to the others.

Setting Up the Robbers Cave Experiment

The researchers set up a series of competitions over 4-6 days, like baseball games and tug-of-war. Winners received prizes - and the losers would receive nothing. Eventually, they began to set up additional conflicts. For example, one group got access to food while the others were told to wait.

The boys eventually started to develop an “us vs. them” mentality. At first, they only exchanged threats and engaged in verbal conflict. Quickly, however, things became more physical. One group burned the other group’s flag, and one group raided the other group’s cabin and stole items from the boys in that group. Things got violent. In surveys taken during this period, the boys shared negative thoughts and stereotypes against the boys in the other group. This proved the first part of Sherif’s theory.

But he wasn’t done.

Final Results of Robbers Cave Experiment

The Robber’s Cave Experiment then went into a final “friction reduction” phase. All 22 boys were given tasks that would benefit the group as a whole. At one point, the researchers set up a challenge in which a truck delivering food was stuck and couldn’t deliver meals. The boys worked together to get the truck unstuck so they could all eat. In another challenge, the boys formed an assembly line to remove rocks that blocked access to the camp’s water tower. Even though the boys had originally felt hostile toward the boys in the opposing group, they were all able to work together to reach a goal that would benefit the whole group.

One thing to note here is that the boys  still  did not know they were a part of an experiment. Sherif never revealed this information to them. As you'll read later in this article, they didn't find out about their participation in the experiment until 50+ years later. That's a long time to not knowing that you impacted psychology forever!

Realistic Conflict Theory

This experiment would go on to be key evidence in the Realistic Conflict Theory (RCT.) Donald Campbell coined this term a few years after Sherif’s experiment. At the time, psychologists had talked about group conflict using sex, food, and other basic needs as motivations. Campbell broadened the theory to include larger goals and a wider categorization of resources.

Thus, realistic conflict theory is based on the assumption that group conflict will become tense whenever these groups must compete for limited resources. These resources could be food, but may also be things like respect, power, or recognition. This tension may lead to stereotyping, violence, and other extreme forms of behavior.

Criticisms of the Robbers Cave Experiment

The Robbers Cave Experiment has continued to be one of the most well-known experiments in the world of social psychology. But not all psychologists sing Sherif’s praises. In fact, the Robbers Cave Experiment has become one of the most well-known experiments due to its questionable ethics.

The purpose of an experiment is to test out a hypothesis. If you cannot support your hypothesis with your experiment, the problem is with the hypothesis - not the experiment. When a psychologist approaches an experiment as a way to prove their hypothesis, things can get tricky. Some critics say that’s what Sherif did with the Robbers Cave Experiment.

Middle Grove Experiment

Before the Robbers Cave Experiment, Sherif conducted a similar experiment at a camp called Middle Grove. But the results didn’t work out like he thought they would. The boys never turned on each other - the bond that they had made at camp before the experiment began was too strong. The “counselors” and Sherif set up pranks to pit the boys against each other, but the boys ended up turning on the counselors instead. They eventually figured out they were being manipulated.

These results were thrown out and only came to light in recent years. With these new findings, psychologists began to refrain from using Robbers Cave as an example in textbooks and lectures.

Eventually, with tweaks to the experiment (rather than the hypothesis,) Sherif came up with a scenario that would support his theory. With results that supported his hypothesis, Sherif felt more comfortable publishing his results. The results attempted to reveal the deeper parts of humanity, but the process surrounding Robbers Cave really just revealed a lot about Sherif.

Robbers Cave Experiment vs. Lord of the Flies

Lord of the Flies didn't exactly have the same resolution as the Robbers Cave experiment. Although the book and experiment are often compared, there are significant differences in how the boys interacted and how their "stories" ended.

(If you haven't read  Lord of the Flies,  skip to the next section. There are spoilers ahead!)

In  Lord of the Flies,  (which, keep in mind, is a fictional story,) a group of boys are stranded on an island after their plane is shot down. They are immediately in distress. They also aren't split up into two groups, although ingroups and outgroups begin to form based on age later in the book. At first, the process of finding food and building a fire is fairly democratic. Rifts really form after individuals or pairs make mistakes. The violence also escalates far beyond what would have been allowed in the Robbers Cave experiment. One boy, Piggy, is killed.

The resolution in the Robbers Cave experiment is the result of a problem that all the boys work to solve together. These tasks start from the very beginning of  Lord of the Flies.  (The book ends with all the boys sobbing after they have been rescued.)

Remember that  Lord of the Flies  was fiction and came from the mind of William Golding. Although, many might argue that the results of the Robbers Cave Experiment were also manipulated...

Legacy of the Robbers Cave Experiment and Muzafer Sherif

Lord of the Flies  will likely be on reading lists for decades to come. Will Sherif's experiment also stand the test of time? It might not. A 2018 book by Gina Perry suggests that the experiment was not as groundbreaking or revealing as it might seem.

Gina Perry is a psychologist and the author of two books that dive into psychology's most famous experiments. (In 2013, Perry published "Behind the Shock Machine: The Untold Story of the Notorious Milgram Psychology Experiments." The book looks at Stanley Milgram 's personal life and how it may have affected the results of his experiment.) Her take on Sherif's work is particularly fascinating. She shows how Sherif actively worked to manipulate the results of the Robbers Cave Experiment to prove his theory.

Two interesting points stand out from her book, although the entire story is worth a read.

• The participants didn't know that they were a part of the study until Perry contacted them herself.
• Sherif was so proud of his experiment that he went back to Robbers Cave to celebrate his 80th birthday.

If you are interested in reading more about the legacy of the Robbers Cave experiment, buy Gina Perry's book "The Lost Boys: Inside Muzafer Sherif's Robbers Cave Experiment" or check it out of your local library. Learning the context behind the experiment puts the results into a different perspective.

Other Examples of Realistic Conflict Theory

While RCT’s most well-known experiment is no longer known for being ethically sound, there is still evidence to support this theory. A lot of this evidence comes from data related to racial tensions and immigration policy.

In 1983, a paper was published on the opposition to school busing and integration. Data taken around that time supported the idea that opposition to busing wasn’t just fueled by racism itself. Group conflict motives also played a role. The threat of another “group” taking scarce resources (access to education) scared whites during that time period.

We hear similar arguments in the present day. Have you ever heard one of your relatives or talk show commentators argue that “immigrants are taking our jobs?” Never mind the validity behind the threat - the perceived threat is enough to cause hostility and tension.

More data and experiments are looking at realistic conflict theory. Psychologists may change their perspectives on intergroup conflict and other related topics. But for now, the Robbers Cave Experiment offers an important reminder that experiments cannot be conducted simply to prove a hypothesis.

Related posts:

• The Monster Study (Summary, Results, and Ethical Issues)
• 40+ Famous Psychologists (Images + Biographies)
• Stanley Milgram (Psychologist Biography)
• The Asch Line Study (+3 Conformity Experiments)
• Facial Feedback Hypothesis (Definition + Examples)

Reference this article:

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What Was the Robbers Cave Experiment in Psychology?

A Landmark Study on Group Conflict

Martin Barraud / Getty Images

• Archaeology
• Ph.D., Psychology, University of California - Santa Barbara
• B.A., Psychology and Peace & Conflict Studies, University of California - Berkeley

The Robbers Cave experiment was a famous psychology study that looked at how conflict develops between groups. The researchers divided boys at a summer camp into two groups, and they studied how conflict developed between them. They also investigated what did and didn't work to reduce group conflict.

Key Takeaways: The Robbers Cave Study

• The Robbers Cave experiment studied how hostilities quickly developed between two groups of boys at a summer camp.
• The researchers were later able to reduce the tensions between the two groups by having them work towards shared goals.
• The Robbers Cave study helps to illustrate several key ideas in psychology, including realistic conflict theory, social identity theory, and the contact hypothesis.

Overview of the Robbers Cave Experiment

The Robbers Cave experiment was part of a series of studies conducted by social psychologist Muzafer Sherif and his colleagues in the 1940s and 1950s. In these studies, Sherif looked at how groups of boys at summer camps interacted with a rival group: he hypothesized that “when two groups have conflicting aims… their members will become hostile to each other even though the groups are composed of normal well-adjusted individuals.”

The participants in the study, boys who were approximately 11-12 years old, thought that they were participating in a typical summer camp, which took place at Robbers Cave State Park in Oklahoma in 1954. However, the campers’ parents knew that their children were actually participating in a research study, as Sherif and his colleagues had gathered extensive information on the participants (such as school records and personality test results).

The boys arrived at camp in two separate groups: for the first part of the study, they spent time with members of their own group, without knowing that the other group existed. The groups chose names (the Eagles and the Rattlers), and each group developed their own group norms and group hierarchies.

After a short time, the boys became aware that there was another group at camp and, upon learning of them, the campers group spoke negatively about the other group. At this point, the researchers began the next phase of the Robbers Cave experiment: a competitive tournament between the groups, consisting of games such as baseball and tug-of-war, for which the winners would receive prizes and a trophy.

What the Robbers Cave Experiment Researchers Found

After the Eagles and Rattlers began competing in the tournament, the relationship between the two groups quickly became tense. The groups began trading insults, and the conflict quickly spiraled. The teams each burned the other group’s team flag and raided their cabin. The researchers also found that the group hostilities were apparent on surveys distributed to the campers: campers were asked to rate their team and the other team on positive and negative traits, and the campers rated their own group more positively than their rivals. During this time, the researchers also noticed a change within the groups as well: the groups became more cohesive.

How Conflict Was Reduced

To determine the factors that could reduce group conflict, the Robbers Cave experiment researchers first brought the campers together for fun activities (such as having a meal or watching a movie together). However, this didn’t work to reduce conflict; for example, meals together devolved into food fights.

Next, Sherif and his colleagues tried having the two groups work on what psychologists call superordinate goals , goals that both groups cared about, which they had to work together to achieve. For example, the camp’s water supply was cut off (a ploy by the researchers to force the two groups to interact), and the Eagles and Rattlers worked together to fix the problem. In another instance, a truck bringing the campers food wouldn’t start (again, an incident staged by the researchers), so members of both groups pulled on a rope to pull the broken truck. These activities didn’t immediately repair the relationship between the groups (at first, the Rattlers and Eagles resumed hostilities after a superordinate goal was achieved), but working on shared goals eventually reduced conflict. The groups stopped calling each other names, perceptions of the other group (as measured by the researchers’ surveys) improved, and friendships even began to form with members of the other group. By the end of camp, some of the campers requested that everyone (from both groups) take the bus home together, and one group bought beverages for the other group on the ride home.

Realistic Conflict Theory

The Robbers Cave experiment has often been used to illustrate realistic conflict theory (also called realistic group conflict theory ), the idea that group conflict can result from competition over resources (whether those resources are tangible or intangible). In particular, hostilities are hypothesized to occur when the groups believe that the resource they’re competing for is in limited supply. At Robbers Cave, for example, the boys were competing for prizes, a trophy, and bragging rights. Since the tournament was set up in a way that it was impossible for both teams to win, realistic conflict theory would suggest that this competition led to the conflicts between the Eagles and Rattlers.

However, the Robbers Cave study also shows that conflict can occur in the absence of competition for resources, as the boys began speaking negatively about the other group even before the researchers introduced the tournament. In other words, as social psychologist Donelson Forsyth explains, the Robbers Cave experiment also demonstrates how readily people engage in social categorization , or dividing themselves into an ingroup and an outgroup.

Critiques of the Robbers Cave Experiment

While Sherif’s Robbers Cave experiment is considered a landmark study in social psychology, some researchers have critiqued Sherif’s methods. For example, some, including writer Gina Perry , have suggested that not enough attention has been paid to the role of the researchers (who posed as camp staff) in the creation of group hostilities. Since the researchers usually refrained from intervening in the conflict, the campers may have assumed that fighting with the other group was condoned. Perry also points out that there are potential ethical issues with the Robbers Cave experiment as well: the children did not know they were in a study—and in fact, many did not realize that they had been in a study until Perry contacted them decades later to ask them about their experience.

Another potential caveat to the Robbers Cave experiment is that one of Sherif’s earlier studies had a very different result. When Sherif and his colleagues conducted a similar summer camp study in 1953, the researchers were not successfully able to create group conflict (and, while the researchers were in the process of trying to incite hostilities between the groups, the campers figured out what the researchers were trying to do).

What Robbers Cave Teaches Us About Human Behavior

Psychologists Michael Platow and John Hunter connect Sherif’s study to social psychology’s social identity theory : the theory that being part of a group has powerful effects on people’s identities and behaviors. Researchers studying social identity have found that people categorize themselves as members of social groups (as the members of the Eagles and Rattlers did), and that these group memberships can lead people to behave in discriminatory and hostile ways towards outgroup members. However, the Robbers Cave experiment also shows that conflict isn’t inevitable or intractable, as the researchers were eventually able to reduce tensions between the two groups.

The Robbers Cave experiment also allows us to evaluate social psychology’s contact hypothesis . According to the contact hypothesis, prejudice and group conflict can be reduced if members of the two groups spend time with one another, and that contact between groups is especially likely to reduce conflict if certain conditions are met. In the Robbers Cave study, the researchers found that simply bringing the groups together for fun activities was not enough to reduce conflict. However, conflict was successfully reduced when the groups worked together on common goals—and, according to the contact hypothesis, having common goals is one of the conditions that makes it more likely that conflict between the groups will be reduced. In other words, the Robbers Cave study suggests it’s not always enough for groups in conflict to spend time together: instead, the key may be to find a way for the two groups to work together.

Sources and Additional Reading

• Forsyth, Donelson R. Group Dynamics . 4th ed., Thomson/Wadsworth, 2006. https://books.google.com/books/about/Group_Dynamics.html?id=VhNHAAAAMAAJ
• Haslam, Alex. “War and Peace and Summer Camp.” Nature , vol. 556, 17 Apr. 2018, pp. 306-307. https://www.nature.com/articles/d41586-018-04582-7
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When is enough, enough? Humanitarian rights and protection for children in conflict settings must be revisited

By zulfiqar a bhutta, robert harding chair in global child health,georgia b dominguez, research assistant, paul h wise, richard e behrman professor of child health and society.

Protecting the lives of children in Gaza and other conflicts requires changes to the rules of engagement and global responses to all conflicts affecting civilian populations, argue Zulfiqar Bhutta and colleagues

Protecting the lives of children in Gaza and other conflicts requires changes to the rules of engagement and global responses to all conflicts affecting civilian populations, argue  Zulfiqar Bhutta and colleagues

The rules of war and existing regulations have become increasingly unable to protect civilians from harm in conflicts around the world. The large death toll among children in Gaza continues to provide the most tragically prominent example of this reality. More broadly, international institutions and humanitarian norms have remained impotent in preventing mass civilian casualties in various settings, including Ukraine, Sudan, and Tigray (1, 2, 3). Much has been said on the genesis of the Gaza conflict and other conflicts, and the tactics being employed by the combatant parties (4), but here we examine the Gaza conflict’s humanitarian effect on children and its implications for the protection of children in other conflict settings around the world.

The attack on Israel by Hamas on 7 October 2023 triggered a devastating military response by Israel that is still ongoing in September 2024. Over the past 10 months in Gaza, the protections afforded civilians in international humanitarian law have been largely ineffective (5). The 1994 genocide in Rwanda is estimated to have killed between 500 000 and 1 million people (6), but other than this there have not been as many civilian deaths in such a short period. The UN Office for the Coordination of Humanitarian Affairs (OCHA) reports that 40 534 Palestinians were killed from 7 October 2023 to 28 August 2024, many of them women and children (7). The reliance on the Gaza Ministry of Health for casualty figures has been questioned, particularly as these numbers do not well distinguish between civilian and combatant deaths and cannot distinguish between the number killed and those who remain listed as missing. Nevertheless, independent assessments have generally substantiated the early tallies of the Gazan ministry, although more recent casualty data may be less reliable as the health information system in Gaza has been largely destroyed and the full numbers may be evident only once the rubble is cleared (8, 9).

The high numbers of child deaths have primarily resulted from the use of explosive munitions in densely populated areas of Gaza under which Hamas has built miles of tunnels for military use. International humanitarian law permits violent attack on identified military targets but not when "the harm to civilians would be excessive in relation to the concrete and direct military advantage anticipated" (10). Israel has yet to provide sufficient evidence to counter the contention that the civilian harm associated with many of its attacks has been disproportionate to the intended military objectives. Israeli attacks have also heavily damaged schools, hospitals, and other healthcare facilities and injured thousands of patients and healthcare workers (11). Hundreds of healthcare workers remain in Israeli detention (12). Other civilian infrastructure has also been struck, including water and sanitation facilities. Hamas and other Palestinian armed groups attacked at least 24 Israeli localities on 7 October, including an open air music festival and "deliberately killed, injured, mistreated, took hostages and committed sexual and gender-based violence against civilians, including Israeli and foreign nationals" (5). Forty children were reportedly killed during these attacks and around 252 hostages were taken (5).

International humanitarian law distinguishes between the why of war and the how of war. Even the strongest justifications for going to war do not justify violating humanitarian laws in how the war is fought. Although it is important to recognise the larger context of the conflict, particularly Israel’s blockade of Gaza (by land, sea, and air) since 2007, this does not legitimise the atrocities perpetrated by Hamas on 7 October, which were clear breaches of international law (10). Neither can these atrocities, however barbaric, legitimise violations of international law in how Israel is conducting its military operations. In May 2024, the International Criminal Court issued arrest warrants for both Hamas and Israeli leaders, charging them with war crimes (13). Humanitarian concerns have also been raised regarding the custodial conditions and legal proceedings of hundreds of Palestinian children in Israeli detention (14).

As well as increasing injury and death among children from military assaults, the destruction of food and water supplies, housing, and healthcare raise serious concerns about the indirect and long term effects of violence on children’s health (15). The UN has reported that children have already died of acute malnutrition and dehydration (5). Recent assessments by the UN’s Food and Agriculture Organisation and the Famine Early Warning Systems Network (FEWS NET) have warned that food insecurity is widespread and, although definitive data are not available (16), conditions of famine may already exist in parts of Gaza, with potential longstanding and possibly intergenerational consequences (17). Recent evidence of polio virus circulating in Gaza, including the first case of type 2 virus in over 25 years, has triggered an emergency vaccination response (18).

Protecting children in war

The nature of violent conflict is always changing. With the intensified wars in Ukraine and Gaza, the decades long predominance of intrastate, civil conflicts, has shifted to interstate wars with a large increase in casualties (see fig 1 in supplementary data). Of special concern for safety of children, are protracted combat operations in densely populated urban areas, particularly when explosive munitions (aerial or artillery) are employed against combatant groups mixed with civilian populations (19). We reviewed the available evidence regarding conflicts with populations under siege or exposed to large scale, urban warfare in modern times. Figure 1 compares the mortality associated with selected, recent urban conflicts, with special attention to deaths among children. Although civilian casualties have been considerable in all examined cases, none have had the number of civilian deaths, especially among children, as in Gaza since last October.

Deaths in recent urban conflicts (see supplementary data for further details and references). Gaza figures up to 28 August 2024; published data on Homs and Gaza do not differentiate between combatants and civilians. There are conflicting claims around total Hamas combatants (Hamas sources claimed 6000 deaths; Israeli sources claimed 12 000)

The UN has identified six violations of international humanitarian law: the killing and maiming of children; recruitment and use of children by armed forces and armed groups; sexual violence against children; attacks against schools or hospitals; abduction of children; and denial of humanitarian access (20). However, children are heavily dependent on several humanitarian requirements that extend to all non-combatants, including the secured ability to exit areas under siege or deemed unsafe, the protection of medical systems, and access to necessary relief supplies. Table 1 lists current international standards supporting the rights of children and civilians in conflict and humanitarian settings. In addition, several UN resolutions also support action to prevent sexual and reproductive violence against women and girls, including resolutions 1612, 1820, 2467, 45/28, and 2601. None provide specific guidance on implementation or consequences for non-compliance.

International standards related to children in armed conflicts (see supplementary data for further details and references)

The special vulnerabilities of children are addressed by a series of provisions in international humanitarian law, including the 1949 Geneva Conventions, 1977 Additional Protocols, the Convention on the Prevention and Punishment of the Crime of Genocide, and the UN Convention on the Rights of the Child. However, processes for ensuring compliance with these provisions remain inadequate and full accountability for violations remains elusive (21). The International Criminal Court (ICC) has authority to investigate and prosecute individuals, including heads of state, for serious breaches. However, the ICC remains dependent on cooperating states to enforce accountability measures (22). It is also evident that states often use their international influence, resources, and sophisticated judicial systems to delay and ultimately impede accountability.

Humanitarian voice for children

Clearly, children share many protections with other non-combatants in these environments, protections that demand immediate implementation in Gaza, Ukraine, Sudan, and in all other areas affected by violent conflict. We argue that children possess distinct claims to protection and care in settings of violent conflict, and that the special developmental vulnerabilities and societal roles of children, many reflected in international law, necessitate special steps in full compliance with humanitarian laws and norms.

The first, and most fundamental, step to protect the children of Gaza is to immediately end combat operations that endanger civilians as well as soldiers: to stop the killing. If there is no cessation of fighting, it is vital to permit and facilitate the evacuation of children, their families, and all civilians to areas of safety (23, 24). Israeli warnings of impending attacks and the establishment of corridors of safe passage have proved largely ineffective. The Geneva Conventions require that a besieging party permit the evacuation of children and other vulnerable civilians from a besieged area, a condition that is not being met by the near total closure of all crossings from Gaza. Unlike the welcome provided by neighbouring countries for the more than five million women and children fleeing the war in Ukraine (25), families in Gaza were not permitted or provided safe passage to move to any of the bordering states. The evacuation of children with catastrophic illness to advanced medical facilities in other countries has also proved far more difficult in Gaza than in Ukraine (26). There is also a widespread fear that departing families and children would never be allowed to return, a fear rooted in the infamous Nakba (catastrophe) of 1948, in which 700 000 Palestinians were displaced by Israeli militias or fled during the Arab-Israeli war of 1948 and barred by Israel from returning to their homes and lands (27).

Second, children are particularly vulnerable to the indirect effects of the war (28). Protections for essential civilian infrastructure remain critical. In addition, adequate relief supplies must be permitted entry and distributed appropriately to civilian populations. The obstruction of adequate relief supplies is a core component of the ICC’s charges of war crimes against Israel (13). Moreover, public statements by some Israeli leaders soon after 7 October have lent support to accusations that Israel is using starvation as a weapon of war (29). This contention, coupled with the destructive military operations, led South Africa to bring allegations to the International Court of Justice that Israel’s actions were "genocidal in character" (3) and the UN special rapporteur on human rights in the Palestinian territories to state that there were reasonable grounds to believe that Israel is committing genocide in Gaza (31).

Displaced and unaccompanied children have distinct needs that too often go unrecognised by both humanitarian agencies and governments. Also critical is the protection and rebuilding of the Gazan health and education systems. Health workers urgently need essential medications, equipment, and other supplies, particularly for children. International medical institutions and professional networks can help facilitate the safe evacuation of children in need of specialised medical care. These networks can also help students and health professionals continue their education so that they will be able to provide crucial health services in Gaza for years to come. Every university and hundreds of schools in Gaza have been damaged, and more than 600 000 children have been out of school since the October attacks. Without immediate protections for schools and support for reopening, education—a critical child right—will be neglected with long term damaging consequences (32, 33).

Third, the global ability to monitor the consequences of war urgently needs to be strengthened. More than 10 months into the conflict, there is still no definitive information on the number of civilian casualties. Although the Gaza Ministry of Health remains the primary source for casualty figures, the infrastructure for assessing casualties has been damaged and there are undoubtedly many killed yet to be discovered (5). Beyond the need for political or legal accountability, accurate information on those who have died is an essential, if tragically belated, way to value them in life. This is of special importance for children, who may have left behind little evidence of their existence other than in the hearts of their families. Currently, documentation relies on a patchwork of UN, academic, non-governmental, and local sources, often with unclear methodologies and political agendas.

Various new technologies could contribute to the assessment of the humanitarian impact of war. These include advanced remote sensing capabilities, modelling strategies, and artificial intelligence—technology currently used to fight a war (34)—should be purposefully and ethically harnessed to assess infrastructure damage and document casualties and humanitarian needs (35). Innovative statistical techniques have been used with existing datasets to estimate excess deaths associated with the armed conflicts in north east Nigeria and Somalia (36, 37). Remote monitoring and artificial intelligence may also contribute to improved systems for assessing the impact of war (38, 39). Academic and non-governmental organisations have pioneered new digital strategies to uncover or confirm military operations and attacks on civilians and civilian infrastructure. These emerging capabilities could contribute to a more fully integrated and authoritative global system for rapidly and accurately assessing the human cost of war.

Lastly, a focus on the humanitarian needs of children in war must not be interpreted as diminishing the humanitarian claims of all adults, soldiers and civilians alike. Indeed, children’s claims have much in common with adult claims. Nevertheless, there has been a long tradition of perceiving and addressing the plight of children as being shaped by a distinct moral, sentimental, and material character. The modern origins of child protections in war were first advanced by the Save the Children movement, which opposed the British blockade of Germany during and after the first world war that contributed to widespread child starvation in eastern Europe (40). Focused attention on the distinct needs and rights of children was also actively pursued during the decade leading up to the adoption of the UN Convention on the Rights of the Child in 1989.

Given the plight of children in Gaza, Ukraine, Sudan, and the many other countries in which children are exposed to violent conflict, we call for a renewed global commitment to the distinct needs and rights of children in crisis. This will require building stronger coalitions and a unified public voice to confront the marginalisation of children in our humanitarian strategies and the impunity with which the perpetrators of humanitarian violations continue their assaults. Although no single meeting or strategic plan can deal with the nature, scope, and urgency of this challenge, a pragmatic, global summit that meaningfully engages affected communities and other essential actors could prove useful in building a sustained, re-energised movement (41). The summit should urgently review existing UN resolutions and guidance and focus on amendments and implementation strategies that ensure protection and evacuation of children from conflict zones. The status quo is unacceptable. The statistics from Gaza not only provide a harsh, synoptic judgment on an enfeebled global morality but should lay the foundation for a renewed humanitarian commitment to the needs and rights of children experiencing the horrors of war.

Contributors and sources ZAB has extensive experience of working in conflict and humanitarian settings and founded the BRANCH (Bridging Research and Action for Women and Children in Conflict and Humanitarian Settings) consortium in 2016. GBD has experience of working with deprived families in south east Asia and PHW is an expert in child health in complex political and security environments and is the juvenile care monitor for the US Federal Court overseeing the treatment of migrant children in US border detention facilities. ZAB and PHW conceptualised and designed this analysis. GBD carried out searches, compiled data, and synthesised the evidence. ZAB led the interpretation of evidence and the writing of this paper with substantial contributions from GBD and PHW. All authors approved the final article for submission. Data were retrieved and compiled from public and electronically available sources. ZAB is the guarantor.

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This article was originally published on the BMJ .

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