Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)
A Common Blue Morpho butterfly lands on the arm of Garbiella as it and hundreds of other butterflies from around the world fill the bird aviary for the next month at the San Diego Zoo Safari Park in San Diego, California March 13, 2015. Called the Butterfly Jungle, the exhibit has over 30 species of butterflies. (Photo by Mike Blake/Reuters)
Boys dressed in historical uniforms stand before a military parade in Red Square in Moscow November 7, 2014. The parade marked the anniversary of the 1941 parade when Soviet soldiers marched through the Red Square towards the front lines of World War Two. (Photo by Maxim Shemetov/Reuters)