Social science literature indicates that immigrants are different from the rest of us. Compared with the general population, they are more likely to possess those qualities especially rewarded by the labor market: ambition, drive, work ethic, and intelligence. This is a common refrain in the paeans Americans make to our bold, tough, and smart forebears. But what other qualities do they share? Are migrants less tolerant of their present circumstances? More likely to believe that something better lies just over the horizon?

Who are the migrants crossing the southern US border?