People take part in the "Bison Race" winter extreme run competition in Zhodino, Belarus, December 5, 2015. (Photo by Vasily Fedosenko/Reuters)

Participants run through the streets of the Back Bay during the 16th annual Santa Speedo Run in Boston, Massachusetts, December 12, 2015. (Photo by Brian Snyder/Reuters)

A participant peeks from his costume before the start of the the annual London Pantomime Horse Race in Greenwich, Britain December 13, 2015. (Photo by Neil Hall/Reuters)

Droid BB-8 arrives at the world premiere of the film “Star Wars: The Force Awakens” in Hollywood, California, December 14, 2015. (Photo by Mario Anzuoni/Reuters)

Firefighters use flashlights to search for survivors among the rubble of collapsed buildings after a landslide hit an industrial park in Shenzhen, Guangdong province, China December 20, 2015. (Photo by Tyrone Siu/Reuters)

A man looks inside an overturned truck after an accident along the road between Nouahibou and Nouakchott, Mauritania December 3, 2009. (Photo by Rafael Marchante/Reuters)

People wear costumes as they participate in the ancient Yule Log dragging tradition during winter solstice celebrations in Riga, Latvia, December 21, 2015. (Photo by Ints Kalnins/Reuters)

Reveller Jacqueline Fernandez looks on in the rain during the 26th Annual Kensington Market Winter Solstice Parade in Toronto, Canada, December 21, 2015. (Photo by Mark Blinch/Reuters)