The coendou porcupine couple 'Joppi' (L) and 'Fletcher' nibble at a vegetables in their enclosure at the zoo in Frankfurt am Main, Germany, 03 December 2015. Coendou porcupines are nocturnal rodents related to porcupines and guinea pigs and native to the rain forests of Central and South America as well as Trinidad. (Photo by Arne Dedert/EPA)

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)

Members of a Star Wars fan club wear costumes of movie characters as they join a midnight premiere of the new Star Wars movie “Star Wars: The Force Awakens” at a cinema in Stuttgart, Germany, late 16 December 2015 night. Numerous fans of the science fiction movie series were gathering to attend one of the midnight premiere screenings all over Germany of the latest movie of the epic series – “Star Wars: The Force Awakens”. (Photo by Nikolai Huland/EPA)

A girl carries a picture of Sheikh Nimr al-Nimr, who was executed along with others in Saudi Arabia, during a protest against the execution in front of the United Nation's building in Beirut, Lebanon January 3, 2016. Sign reads, “The martyr scholar Nimr al-Nimr”. (Photo by Hasan Shaaban/Reuters)

Tibetan monks dressed as demons attend the Beating Ghost festival at the Yonghe Temple, also known as the Lama Temple, in Beijing on March 19, 2015. The Beating Ghost festival, or Da Gui festival in Chinese, is an important ritual of Tibetan Buddhism and is believed to expel evil spirits and shake off troubles. (Photo by Wang Zhao/AFP Photo)

A wolverine is pictured during its first public appearance at the Animal Park of Sainte-Croix in Rhodes, eastern France on January 28, 2016. (Photo by Frederick Florin/AFP Photo)

Dancers from the School of American Ballet Chloe Ellis (R) and Amarra Hong (L) prepare for a performance at the Queens Theatre in the Queens borough of New York February 28, 2016. (Photo by Shannon Stapleton/Reuters)

A U.S. army soldier exercises in front of a M270A1 multiple launch rocket system as they prepare for a live-fire training exercise of the 6-37th Field Artillery Regiment at a training area near the demilitarized zone separating the two Koreas, in Cheorwon, South Korea, March 9, 2016. (Photo by Kim Hong-Ji/Reuters)