Mariam, a 9-year-old girl, carries her brother as she stands with other children at an underground ancient cemetery in Jabal al-Zawiya in the southern countryside of Idlib November 26, 2014. Residents are using ancient caves and cemeteries as underground shelters to hide in during shelling from forces loyal to President Bashar al-Assad. Picture taken November 26, 2014. (Photo by Khalil Ashawi/Reuters)

A mahout (a person who rides an elephant) decorates his elephant using chalk while preparing for the Elephant Festival at Sauraha in Chitwan, south of Kathmandu, December 26, 2014. Elephants and mahouts from Chitwan will participate in the Elephant festival, which involves elephant races, elephants playing an exhibition soccer match and taking part in various other sporting activities. The event will start from 26 December and will end on 30 December, 2014. (Photo by Navesh Chitrakar/Reuters)

Yaks head towards the Everest base camp in Solukhumbu District April 28, 2014. (Photo by Navesh Chitrakar/Reuters)

People take pictures of the sunset in Berlin October 27, 2014. (Photo by Hannibal Hanschke/Reuters)

A Santa Claus puppet holding a Christmas tree is pictured against the sun in Berlin November 23, 2014. (Photo by Hannibal Hanschke/Reuters)

Hungarian wrestlers fight during the Hungarian wrestling Championship in Budapest November 29, 2014. (Photo by Laszlo Balogh/Reuters)

Steam emerges from a cooling tower of the nuclear power plant Leibstadt near Leibstadt, Switzerland, November 18, 2014. (Photo by Arnd Wiegmann/Reuters)