The Boeoegg, a giant symbolic snowman made of wadding and and filled with firecrackers burns on top of a bonfire in Sechselaeuten square on April 24, 2017 in Zurich. When the bells of the Saint Peter's church chime six o'clock, the bonfire under the snowman is set in fire and the guildsmen wearing historical costumes ride around the bonfire. The faster the head of the snowman explods the warmer and more beautiful the summer will be. (Photo by Michael Buholzer/AFP Photo)

A participant covered in coloured powder gestures as she stands near a Syrian army soldier during “I Love Damascus” marathon at Umayyad Square in Damascus, Syria October 7, 2016. (Photo by Omar Sanadiki/Reuters)

A photographer could bear-ly believe his eyes when a bear started waving at him. The friendly animal wandered to the front of his enclosure before sitting back in full view of zoo guests. He then lifts his powerful paw and excitedly waves in an almost human-like way at his new audience. The hilarious encounter was captured by keen photographer Andrey Slepnev, 31, while on a trip to Madrid Zoo, Spain on March 24, 2016. (Photo by Andrey Slepnev/Caters News)

An injured girl reacts at a site hit by an airstrike in the rebel-held Douma neighbourhood of Damascus, Syria November 7, 2016. (Photo by Bassam Khabieh/Reuters)

This photo take on December 16, 2016 shows macaques monkeys playing on a motorbike in the grounds of a temple in Jaipur in the Indian state of Rajasthan. (Photo by Dominique Faget/AFP Photo)

An employee controls the arms of a manned biped walking robot “METHOD-2” during a demonstration in Gunpo, South Korea, December 27, 2016. It stands 13-feet (3,96 m) tall, weighs 1.3 tons and wields a pair of 286-pound (129,73 kg), motion-tracking metal arms. (Photo by Kim Hong-Ji/Reuters)

At Studio 54, an unidentified trio of two woman and one man recline on a banquette, miming unconsciousness, New York, New York, September 29, 1977. (Photo by Allan Tannenbaum/Getty Images)

For the Torajan people of Indonesia, death is part of a spiritual journey: families keep the mummified remains of their deceased relatives in their homes for years – and traditionally invite them to join for lunch on a daily basis – before they are eventually buried. Here: Todeng died in 2009. A young relative of his, Sam, lights him a cigarette and changes his glasses. (Photo by Claudio Sieber Photography/The Guardian)