Purev and Buyantogtokh enjoy the warmth of the fire in the snow in Altai Mountains, Mongolia, September 2016. Navigate the snowy wilds of Mongolia with this nomadic reindeer herding family. Photographer Joel Santos dived 1000km into the depths of Northern Mongolia to visit the Ganbaa family near Khovsgol Lake. (Photo by Joel Santos/Barcroft Images)

In this photo taken Friday, December 9, 2016, young ballerinas practice under the instruction of Kenyan ballet dancer Joel Kioko, 16, in a room at a school in the Kibera slum of Nairobi, Kenya. (Photo by Ben Curtis/AP Photo)

A Filipino flagellant crawls along a street on Maundy Thursday, in San Fernando city, Pampanga Province, north of Manila, Philippines, 24 March 2016. Many Filipino Catholic penitents mark the Holy Week by submitting to different forms of physical penance in the hopes of being forgiven for their sins. (Photo by Francis R. Malasig/EPA)

Rebel fighters from the Jaish al- Fatah (or Army of Conquest) brigades manoeuver an alleged explosive- rigged make- shift armoured vehicle during a major assault on Syrian government forces West of Aleppo city on October 28, 2016 Syrian opposition fighters launched a major assault on government forces to break a months- long siege of rebel- held neighbourhoods of the battered city of Aleppo. Rebel groups including the powerful Ahrar al- Sham faction and former Al- Qaeda affiliate Fateh al- Sham Front fired waves of rockets into government- held western Aleppo, killing at least 15 civilians, a monitor said. (Photo by Omar Haj Kadour/AFP Photo)

A member of the punk group p*ssy Riot is restrained by a member of the Cossack militia in Sochi, Russia, on Wednesday, February 19, 2014. Cossack militia attacked the p*ssy Riot punk group with horsewhips on Wednesday as the group tried to perform under a sign advertising the Sochi Olympics. The group had gathered to perform in a downtown Sochi restaurant, about 30km (21miles) from where the Winter Olympics are being held.They left the restaurant wearing bright dresses and ski masks and had only been performing for a few seconds when they were set upon by Cossacks. (Photo by Morry Gash/AP Photo)

Christopher Tubbs embraces his wife Sarah after arriving home during the homecoming of the USS Enterprise at the Norfolk Naval Station July 15, 2011 in Norfolk, Virginia. In its 184 days away from Norfolk, the USS Enterprise cruised nearly 60,000 miles while supporting operations in Afghanistan and Iraq. (Photo by Win McNamee/Getty Images)

A chimpanzee relaxes in the shade at the Safari Park as the popular attraction prepares for the upcoming Jewish festival of Pesach (Passover) on April 14, 2008 in Ramat Gan near Tel Aviv, Israel. (Photo by David Silverman/Getty Images)

LOCOG Chair and former Olympian Lord Sebastian Coe holds a prototype design of the new golden Olympic Torch during its unveiling at St Pancras Station on June 8, 2011 in London, England. (Photo by Dan Kitwood/Getty Images)