Newly-wed couples attend their group wedding ceremony which was held as part of the Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province January 6, 2016. As many as 15 couples attend this mass wedding ceremony. (Photo by Aly Song/Reuters)

An arrow-head discovered in 2006 by Archaeologists of the University of Cambridge Archaeological Unit, is displayed by one of the team uncovering Bronze Age wooden houses, preserved in silt, from a quarry near Peterborough, Britain, January 12, 2016. Archaeologists said on Tuesday they had discovered what were believed to be the best-preserved Bronze Age dwellings ever found in Britain, providing an extraordinary insight into prehistoric life from 3,000 years ago. (Photo by Peter Nicholls/Reuters)

Serena Williams of the U.S. serves during her first round match against Italy's Camila Giorgi at the Australian Open tennis tournament at Melbourne Park, Australia, January 18, 2016. (Photo by Jason O'Brien/Reuters)

Members of the Shanxi Folk Dance and Music Troupe perform during a rehearsal before a show at the Orient Museum in Lisbon February 1, 2016. The show is part of the Chinese New Year Celebrations program of Orient Museum in Lisbon. (Photo by Rafael Marchante/Reuters)

People in hard hats in a rage room in Moscow, Russia on January 27, 2016. The Debosh stress relief service gives its customers an opportunity to smash the rage room up with sledgehammers and bats to relieve stress and tension. (Photo by Artyom Geodakyan/TASS/Barcroft Media)

Clowns sit in the pews and hold hands across the aisle of the All Saints Church during the Grimaldi clown service in Dalston, north London, February 7, 2016. The Clowns International 70th annual service brings together professional clowns from Britain and Europe in a service of remembrance to the famous British clown Joseph Grimaldi, who died in 1837. (Photo by Peter Nicholls/Reuters)

A 3-month-old ethnic Tujia baby girl is pictured next to her father as they wait for a traditional ethnic Tujia wedding feast during celebrations marking the Lunar New Year in Ziqiu town, Changyang county of China’s Hubei province, February 15, 2016. (Photo by Jason Lee/Reuters)

An Israeli teenager crawls through mud as he participates in an annual combat fitness training competition, as part of his preparations ahead of his compulsory army service, near Kibbutz Yakum, central Israel February 19, 2016. (Photo by Baz Ratner/Reuters)