Asylum seekers at Holot detention center, Israel. Photo: Getty

Exposure to foreigners or new ethnic groups causes people to adopt hardened anti-immigration attitudes, a US study shows.

The research suggests developed nations should expect a shift to conservative politics and the prospect of conflict in areas with increased immigration.

Ryan D. Enos of Harvard University wanted to see whether people really are hostile to newcomers and not just reacting to political statements.

To do it, he added two Hispanic men to train carriages in Boston full of unknowing Anglo-whites living in homogeneous communities.

The Hispanic men, who kept getting on the same trains day after day, reported some unease in the carriage.

“Because we are chatting in Spanish, they look at us,” one said. “I don’t think it is common to hear people speaking in Spanish on this route.”

The men reported that other passengers were generally friendly to them but also reported that they felt people noticed them for “not being like them and being Latino”.

Dr Enos also surveyed the Anglos in the carriages, before and after the arrival of the Hispanics, and found that they hardened their anti-immigration feelings.

However, these results also suggest that more prolonged contact between two different groups can diminish the initial impulse to keep foreigners out.

Dr Enos’s findings are published today in PNAS.

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