A man relaxes at a downtown park in Seoul. The pronounced demographic shift triggered by a plummeting birth rate and soaring life expectancy is seen as one of the greatest challenges facing Asia's fourth-largest economy. Kim Jae-Hwan/AFP/Getty Images hide caption

itoggle caption Kim Jae-Hwan/AFP/Getty Images

A chocolate cake is shaped like Europe, with new EU members Romania and Bulgaria (far right), at a welcoming ceremony for their entry into the bloc on Dec. 14, 2006. Curbs on the movement of citizens of the two countries end on Jan. 1, raising fears in Western Europe of an influx of Bulgarian and Romanian workers. Thierry Charlier/AP hide caption

itoggle caption Thierry Charlier/AP

The Senate has passed a sweeping immigration bill, widely seen as the product of the "Gang of 8," a group that includes Sens. John McCain, R-Ariz. (left), and Sen. Chuck Schumer, D-N.Y. The two shook hands before Thursday's final vote. J. Scott Applewhite/AP hide caption

itoggle caption J. Scott Applewhite/AP

Construction is underway on the Itaquerao stadium in Sao Paulo, shown here June 12. The stadium will be the venue for the opening ceremony and game of the 2014 FIFA World Cup in Brazil, and many migrants are among the laborers working on the project. Sebastiao Moreira/EPA/Landov hide caption

itoggle caption Sebastiao Moreira/EPA/Landov

"Immigrants are more fertile, and they love families," former Florida Gov. Jeb Bush said Friday at the Faith and Freedom Coalition conference. Bush's statement, in support of immigration reform, struck an odd note with many who hear it. Mark Wilson/Getty Images hide caption

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