Wakhi nomad women milk yaks in Wakhan, Afghanistan. About 12,000 villagers live at an altitude of 4,500 metres in the harsh, desolate terrain. The Wakhi people live a simple, relaxed life with their livestock. (Photo by Eric Lafforgue/Barcroft Images)

People ride bicycles in Halloween costumes during “Bike Kill 13” in the Brooklyn borough of New York City, October 29, 2016. “Bike Kill” is an annual gathering of builders and riders of home-made bicycles that culminates in a tall bike jousting competition. (Photo by Stephanie Keith/Reuters)

A picture shows the blood stained floor of a kindergarten following reported shelling in the rebel-held area of Harasta, on the northeastern outskirts of the capital Damascus, on November 6, 2016. At least four children were killed and 19 people injured in the government strike in Harasta, according to the Syrian Observatory for Human Rights. (Photo by Sameer Al-Doumy/AFP Photo)

A group of people wearing Santa Claus hats and swimming suits participate in the 13th charity Great Santa Claus Run in downtown Budapest, Hungary, Sunday, December 11, 2016. (Photo by Balazs Mohai/MTI via AP Photo)

People in traditional costumes prepare before competing in the 55th Verdiales music contest in Malaga, southern Spain December 28, 2016. Verdiales is a form of traditional Flamenco music, which is common in the province of Malaga. Members of singing groups, known as “pandas”, wear traditional costumes decked with flowers and other accessories as they perform in the contest, which is held annually on December 28. (Photo by Jon Nazca/Reuters)

People view live owls at, Owl's Forest which is located on the bottom floor of a building along a bustling street in the Harajuku area on Friday November 04, 2016 in Tokyo, Japan. Visitors can pet owls at the business. It is located next to one of Tokyo's many cat cafes. (Photo by Matt McClain/The Washington Post)

An aerial view of a livestock enclosure of the Himba people, in October, 2014, in the Namib Desert, Namibia. A photographer has captured a bird's eye view of the stunning Namib Desert from a paraglider. Theo Allofs travels the world taking stunning pictures of untouched landscapes from a unique perspective. Soaring 300 metres above ground, Theo shot the yellow sand dunes, dry red river beds and remote townships in Namibia. (Photo by Theo Allofs/Barcroft Media)

People walk past debris on May 3, 2015 in Bhaktapur, Nepal. A major 7.8 earthquake hit Kathmandu mid-day on Saturday, and was followed by multiple aftershocks that triggered avalanches on Mt. Everest that buried mountain climbers in their base camps. (Photo by David Ramos/Getty Images)