Rio de Janeiro, Brazil, February 3, 2008—As smiling "samurai" look on, Angela Bismarchi, 36, rehearses her ode to a centennial celebration of Japanese immigration to Brazil—a theme of this year's Carnival in Rio de Janeiro. The next day she was scheduled to have nylon wires temporarily implanted in her eyes to give them an Asian overhaul. (Video: Rio Carnival Honors Japanese [January 31, 2008].)

Carnival itself has undergone many revisions as cultures around the world have added their idiosyncratic slants to the festivities—from bead throwing at New Orleans's Mardi Gras to animal sacrifice in Bolivia.

Historically Carnival has been a last hurrah before the Christian season of Lent—40 days of fasting and penitence beginning on Ash Wednesday. But its roots reach at least as far back as ancient Rome's Saturnalia, a hedonistic winter celebration of Saturn, god of the harvest.

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