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)

People ride a motorcycle near Koudoukou Mosque where Pope Francis meets Imam Tidiani Moussa Naibi in Bangui, Central African Republic, November 30, 2015. (Photo by Stefano Rellandini/Reuters)

A model falls over on the runway during the SECCRY Hu Sheguang Collection 2014 Show during Mercedes-Benz China Fashion Week, March 30, 2014, in Beijing. (Photo by Lintao Zhang/Getty Images)

A tourist takes photos of an Aurora Borealis display (Northern Lights) over the Bals-Fiord north of the Arctic Circle, near the village of Mestervik late September 30, 2014. (Photo by Yannis Behrakis/Reuters)

Children exercise before a wrestling practice session at an old Basque ball game gymnasium in downtown Havana, October 30, 2014. (Photo by Alexandre Meneghini/Reuters)

A child looks at a polar bear swimming under a water in its enclosure on a hot summer day at Prague Zoo, Czech Republic, July 30, 2015. (Photo by David W. Cerny/Reuters)

Selena Gomez, left, and Taylor Swift arrive at the MTV Video Music Awards at the Microsoft Theater on Sunday, August 30, 2015, in Los Angeles. (Photo by Jordan Strauss/Invision/AP Photo)

Princess Anne, Princess Royal waves off Zara Philips as she eaves Canongate Kirk on the afternoon of her wedding to Mike Tindall on July 30, 2011 in Edinburgh, Scotland. (Photo by Chris Jackson PT/Getty Images)