Migration Trends: Young and Poor Move to Lands of Aging Rich

The world's most troublesome borders for illegal migration have one thing in common, more older people on one side than the other. Large gaps in the median age on either side show a difference of 19 years for Northern Africa and Southern Europe, and 11 years for the United States and Central America. Age differences between sending and receiving nations are a powerful force exerting migratory pressures on borders, argues Joseph Chamie, a demographer and former director of the UN Population Division.