A man from Dinka tribe holds his AK-47 rifle in front of cows in a Dinka cattle herders camp near Rumbek, capital of the Lakes State in central South Sudan December 14, 2013. (Photo by Goran Tomasevic/Reuters)

More than 400 people stripped off and ran into freezing waters to celebrate the autumn equinox – and raise money for charity at Druridge Bay, Britain, September 25, 2016. It was the largest turnout the North East Skinny Dip has ever seen in its five-year history, and it was also the first time it has ever rained on the morning of the event. Revellers gathered from 5.30am on Sunday at Druridge Bay, in Northumberland, before baring all in the North Sea. (Photo by David Charlton Photography)

Dancers attend a photocall for the new “The One – Grand Show” at Friedrichstadt-Palast in Berlin, Germany September 28, 2016. The show, which features costumes by French fashion designer Jean Paul Gaultier, premieres on 06 October. (Photo by Hannibal Hanschke/Reuters)

Amy Rimmer, Research Engineer at Jaguar Land Rover, demonstrates the car manufacturer's Advanced Highway Assist in a Range Rover, which drives the vehicle, overtakes and can detect vehicles in the blind spot, during the first demonstrations of the UK Autodrive Project at HORIBA MIRA Proving Ground in Nuneaton, Warwickshire on Friday October 21, 2016. (Photo by Fabio De Paola/PA Wire)

A huge wave crashes against Castlerock pier as professional surfer Al Mennie waits on a break in the swell on December 22, 2016 in Coleraine, Northern Ireland. Storm Barbara is expected to cause major travel disruption when it hits northern parts of the UK later with 90mph winds predicted. The Met Office has issued an amber warning with the worst effects of the storm expected on Friday and Saturday. (Photo by Charles McQuillan/Getty Images)

Passengers prepare to take part in the No Pants Subway Ride in Prague, Czech Republic, Sunday, January 8, 2017. The No Pants Subway Ride began in 2002 in New York as a stunt and has taken place in cities around the world since then. (Photo by Petr David Josek/AP Photo)

A protester from the People for the Ethical Treatment of Animals (PETA) displays a placard from a bathtub as a people looks on during a demonstration to call on the public to eat more vegetables to save water, in Sao Paulo on August 2, 2016. (Photo by Cris Faga via ZUMA Wire)

A close up of ornaments of centuries-old idols of Lord Buddha during the Pancha Daan, Five donation, festival in Bhaktapur, Nepal, 30 August 2016. Thousands of Buddhist pilgrims observe the main day of the Pancha Daan also known as a five summer gifts (rice, grain, salt, money and fruits) festival which is observes for world peace and human welfare. (Photo by Narendra Shrestha/EPA)