Habitat for Humanity rebuilds a house in the Upper Ninth Ward of New Orleans.

Big Cypress National Preserve in the Florida Everglades.

A polar bear.

House Speaker Nancy Pelosi walks to her weekly press conference. As lawmakers who initially voted against the measure slowly began changing their votes, there was an increasing sense of optimism that the bill would pass. (Charlie Archambault for USN&WR)

Michelle Obama on stage with daughters Malia (left) and Sasha at the Democratic National Convention 2008 at the Pepsi Center in Denver.

Cindy McCain takes the stage to speak in the opening session of the Republican National Convention in St. Paul, Minn.