A man admires a sculpture in the series entitled 'Circle of Animals/Zodiac Heads' by Chinese artist Ai Weiwei in the courtyard of Somerset House on May 11, 2011 in London, England. The installation comprises of 12 bronze heads of animals which feature in the Chinese zodiac. The artist Ai Weiwei, who is outspoken in his criticism of the Chinese administration, was detained by authorities in Beijing on April 3, 2011 and his whereabouts remain unknown.

A man rides a horse through a bonfire on January 16, 2012 in the small village of San Bartolome de Pinares, Spain. In honor of San Anton, the patron saint of animals, horses are riden through the bonfires on the night before the official day of honoring animals in Spain. (Photo by Jasper Juinen/Getty Images)

A young man shows off his new Sony PlayStation Vita portable gaming device that he just bought at the Sony Store during the official German launch of the new Vita on February 21, 2012 in Berlin, Germany. Several hundred video gaming enthusiasts waited hours in line to be among the first to buy the new device. (Photo by Sean Gallup/Getty Images)

An immigrant from Mali rests at the Greek-Macedonian border before an attempt to flee to Macedonia May 13, 2015 village of Idomeni in Kilkis prefecture May 13, 2015. Hundreds of mostly Afghan, Syrian, and African immigrants cross daily from Greece into Macedonia on their way to northern European countries; most of them are turned back by Macedonian border guards. (Photo by Yannis Behrakis/Reuters)

Visitors walk past a train-shaped ice sculpture ahead of the 31st Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province, January 4, 2015. The winter festival will be officially opened on January 5, 2015. (Photo by Kim Kyung-Hoon/Reuters)

An Indonesian worker carries a giant candle at a traditional Chinese candle maker for the upcoming Lunar New Year in Bogor, Indonesia, 27 January 2015. The Chinese Lunar New Year, known here as Imlek, is only three weeks away. The whole city is getting decked out to celebrate the event on 19 February 2015. (Photo by Adi Weda/EPA)

Newborn orangutan Rieke is presented during a press conference at Berlin Zoo, in Berlin, Germany, February 6, 2015. The baby was born on January 12, 2015 weighing 2,290 grams and is bottle-fed by keepers. (Photo by Ralf Hirschberger/EPA)