U.S. soldiers from the 3rd Cavalry Regiment take part in an artillery exercise on forward operating base Gamberi in the Laghman province of Afghanistan December 24, 2014. (Photo by Lucas Jackson/Reuters)

A polar bear plays with a pylon during celebrations marking its first birthday in an enclosure at Tierpark Hellabrunn zoo in Munich December 9, 2014. (Photo by Michaela Rehle/Reuters)

Gabriella Papadakis and Guillaume Cizeron of France perform during the ice dance skating event at the ISU Grand Prix of Figure Skating final in Barcelona December 13, 2014. (Photo by Albert Gea/Reuters)

People view Singpoli Group's inaugural Rose Parade float as it undergoes its finishing touches in Pasadena, California December 30, 2014. The 126th Rose Parade will take place on New Years Day in Pasadena. (Photo by Jonathan Alcorn/Reuters)

Mechanics work in the Buggy belonging to Argentina's Manuel Sisterna and Adrian Echegaray during technical verification ahead of the Dakar Rally 2015 in Buenos Aires January 1, 2015. (Photo by Enrique Marcarian/Reuters)

Bulgarian men dance in the icy waters of the Tundzha river during a celebration to commemorate Epiphany Day in the town of Kalofer January 6, 2015. It is believed that the ritual will bring good health to the participants throughout the new year. (Photo by Stoyan Nenov/Reuters)

A member of the Edo Firemanship Preservation Association displays his balancing skills atop bamboo ladder during a New Year presentation by the fire brigade in Tokyo January 6, 2015. (Photo by Thomas Peter/Reuters)

A man falls from an ox cart as he competes during an ox cart competition near U Bein bridge, in Mandalay March 22, 2015. (Photo by Soe Zeya Tun/Reuters)