A cultural dance group waits to perform at Gambela stadium during Ethiopia's Nations and Nationalities Festival in Gambela town, in Ethiopia December 8, 2015. Picture taken December 8, 2015. (Photo by Tiksa Negeri/Reuters)

Miss Colombia 2015 Ariadna Gutierrez rehearses for the upcoming Miss Universe telecast while at Planet Hollywood Resort and Casino in Las Vegas, Nevada, December 12. 2015. (Photo by Darren Decker/Reuters/The Miss Universe Organization)

A pig's head is seen in a basin after it was slaughtered it in the village of Azerany, Belarus, December 12, 2015. (Photo by Vasily Fedosenko/Reuters)

Damaged buildings are pictured at night in Aleppo, Syria December 11, 2015. (Photo by Ammar Abdullah/Reuters)

Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

A woman sells vegetables near a Metro train station in downtown Lima, Peru December 1, 2015. (Photo by Mariana Bazo/Reuters)

Participants pose for a photographers during the Miss Iraq Pageant in Baghdad, December 19, 2015. (Photo by Ahmed Saad/Reuters)

People are reflected in mirrors as they walk in a busy shopping district in Tokyo, Japan, December 25, 2015. (Photo by Thomas Peter/Reuters)