Brad Snead walks past melting ice on the Cook Inlet beach, Saturday, March 26, 2011, in Kenai, Alaska, while looking for agates. (AP Photo/Peninsula Clarion, M. Scott Moon)

Miranda Kerr poses at the David Jones Spring/Summer fashion preview on Burke Street on August 10, 2011 in Melbourne, Australia. (Photo by Lucas Dawson)

Protestors affiliated with the Occupy Wall Street movement block the entrance to the Iowa Democratic Party headquarters during a protest on December 29, 2011 in Des Moines, Iowa. Thirteen people were arrested during the protest. (Photo by Andrew Burton/Getty Images)

The Sydney Skyline is seen before the lights are switched off for Earth Hour on March 26, 2011 in Sydney, Australia. Earth Hour encourages individuals around the world to turn off their lights for one hour at 20:30 local time on March 26, 2011 to take a stand against climate change. The largest Earth Hour was in 2010 when 128 countries participated.

A visitor to ''The Cult of Beauty: The Aesthetic Movement 1860-1900'' exhibition at The V&A Museum looks at sculptures by Thornycroft (L) and Watts on March 30, 2011 in London, England. This exhibition brings together for the first time many masterpieces in painting, sculpture, design and furniture as well as fashion and literature and runs from April 2nd to July 17th 2011.

Andy Swan “Zippy the Clown” from Sacramento, California, drives his “elelphant” car during a break at the 2011 Clowns of America International Convention on April 15, 2011 in Anaheim, California. Several hundred clowns, from all over the United States and from as far as Puerto Rico and Germany, are attending the convention to compete in skits and hone their skills in the art of balloon-making and face-painting. (Photo by Kevork Djansezian/Getty Images)

Bonhams expert Michaela Vergottis holds a yellow Jade Chinese Imperial Sceptre on May 9, 2011 in London, England. The piece which is thought to have been taken by British Troups during the Boxer Rebellion is expected to fetch between £800,000 – 1.2 M GBP when it goes on sale at the “Chinese Art” sale at Bonham's auction house on May 12, 2011. (Photo by Dan Kitwood/Getty Images)

Newly commissioned 2nd lieutenants throw their caps in the air as a team of F-16 Air Force Thunderbirds fly over the 2011 graduating class of the U.S. Air Force Academy on May 25, 2011 in Colorado Springs, Colorado. A total of 1,021 graduates received their diplomas in front of their families and dignitaries at the Academy's Falcon Stadium. (Photo by John Moore/Getty Images)