A boy performs a masked dance as he participates in a parade during the National Encounter of Mask festival in Barva de Heredia October 30, 2015. (Photo by Juan Carlos Ulate/Reuters)

In this Saturday, August 16, 2014 photo, Mandy Stokes stands with her daughter Molly Kate Stokes next to a large alligator weighing 1011.5 pounds measuring 15-feet long is pictured in Thomaston, Ala. The alligator was caught in the Alabama River near Camden, Ala., by Mandy Stokes and family. (Photo by Sharon Steinmann/AP Photo/Al.com)

A giant Rubber Duck created by Dutch artist Florentijn Hofman is towed along Hong Kong's Victoria Habour Thursday, May 2, 2013. Since 2007 the 16.5-meter (54 feet)-tall Rubber Duck has traveled to various cites including Osaka, Sydney, Sao Paulo and Amsterdam. (Photo by Vincent Yu/AP Photo)

Russian pop art photographer Sergey Chilikov captures a nation liberated from the social oppression of late-era Soviet rule – at parties, in the streets, and bouncing high. His exhibition, Photoprovocations, will be at Photo London, 19-22 May. Here: Yoshkar-Ola, Matrosova Street (1995). (Photo by Sergey Chilikov)

Lance Sergent Martin Mitchell (R) pins medals to Coldstream Guardsman Martin Hughes in the Tailor Shop in Wellington Barracks on April 20, 2011 in London, England. Soldiers involved in the Royal Wedding of Prince William and Catherine Middleton are preparing their ceremonial duties ahead of the day. (Photo by Oli Scarff/Getty Images)

Members of the Kaisokah Moko Jumbies perform with fire on the waterfront near their San Fernando, Trinidad base February 10, 2015. (Photo by Andrea De Silva/Reuters)

David Sharp, an engineer with Lockheed Martin, displays the “Samurai Flyer”, an aviation design inspired by the maple seed, during the Association for Unmanned Vehicle Systems International Conference August 16, 2011 in Washington, DC. Lockheed Martin unveiled the new design and demonstrated vertical takeoff and landing, stable hover, and on-board video streaming of the aircraft during their demonstration. (Photo by Win McNamee/Getty Images)