May 9 (UPI) -- New research can help explain why inter-ethnic conflicts intensify so quickly.
Social experiments suggest aggression expressed toward different ethnic groups is more likely to be imitated, allowing hostility toward minorities to spread like a contagion.
Researchers in Germany, the Czech Republic and Slovakia studied the attitudes toward Roma people of schoolchildren in eastern Slovakia. The Roma people are a minority and face significant prejudices.
Schoolchildren were allowed to partake in a "joy-of-destruction game," a game allowing participants to express their destructive tendencies. Two participants are granted two euros each. They're given the option to either pay 20 cents to reduce the other's allotment or keep the money as is. Each player remains anonymous and faces off with each opponent only once.
Though the players don't see their opponent, they're told their names -- made-up names. Researchers assigned the players names that suggest one of two ethnicities: Slovak or Roma.
The game was designed so that the participating adolescents were aware of the choice made by the player before them.
The experimental game showed players are influenced by the decisions of their peers. Players were more likely to make a destructive decision after witnessing the destructive tendency of the player before them. This destructive effect was doubled when the participant faced a Roma opponent instead of a member of their own ethnic group.
In a followup test, researchers asked another group of students to rate the appropriateness of the behaviors exhibited by the game-players. In a social setting free of hostile peers, destructive behavior toward both Slovak and Roma players were judged to be equally negative.
But when students learned that many of the players had witnessed similar destructive actions before acting destructively toward Roma players, the students were more likely to deem the actions appropriate.
The research, published this week in the journal PNAS, suggests the perception of hostile behavior toward members of one's own social group is less contingent on the social environment. Likewise, hostility toward members of a minority group can be imitated, normalized and spread like a disease under certain social circumstances.
"Our results suggest that fragile social norms can lead to a sudden change in individual behavior towards other ethnic groups -- from good coexistence to aggression," Max Planck scientist Jana Cahlíková said in a news release.
The findings could help explain how ethnic conflict can quickly escalate in places like Bosnia, Liberia and Rwanda, where groups that have lived peacefully for decades suddenly turn violent.