Two young boys kneel on stools on either side of a round table as one uses a match to this the other's cigarette, November 12, 1928. (Photo by FPG/Getty Images)

In this photo taken on August 26, 2017, a contestant of the “fantasy” category prepares to be judged during the Daegu International Bodypainting Festival in Daegu, South Korea. The bodies of dozens of female models turned into living canvases this weekend as they allowed delicate brush strokes and flamboyant illustrations to cover up their bare skin. They are part of the 2017 Daegu International Bodypainting Festival along with top artists from 10 countries that runs until August 27 in South Korea's southeastern city of Daegu. (Photo by Ed Jones/AFP Photo)

A woman dressed for la “La Diablada” festival walks down a road in Pillaro, Ecuador, Friday, January 6, 2017. Local legend holds that anyone who adopts a costume for the celebration and wears it at the event six years in a row will have good luck. (Photo by Dolores Ochoa/AP Photo)

The photography of Art Wolfe covers the globe, capturing landscapes, wildlife, and cultures from every continent; here he talks through a selection of his favourite images. Art Wolfe is an American photographer and conservationist. His photographs have been noted by environmental advocacy groups for their “stunning” visual impact. Here: Snowy owlets (Bubo scandiacus), Arctic National Wildlife Refuge, Alaska, USA. (Photo by Art Wolfe/Art Wolfe Stock)

Sarah Bui poses for photographer, Brian Le around blossoming cherry trees, near the Tidal Basin on Thursday March 23, 2017 in Washington, DC. (Photo by Matt McClain/The Washington Post)

Two young women, having enjoyed a drink at a party, dance together in Tehran, Iran. Although unrelated men and women are forbidden to socialise together many people ignore these strictures in the privacy of their own homes. (Photo by Hossein Fatemi/Reuters/Panos Pictures/Courtesy of World Press Photo Foundation)

Mazouza Bouglada, 86, a berber woman from the Chaouia region, who has facial tattoos, poses for a photograph in Taghit in the Aures Mountain, Algeria October 8, 2015. Bouglada was tattooed aged 7 by a nomadic man from the Sahara region. She was advised by her mother to get tattooed. The more she got tattooed the more she showed off. Even if she still remembers the pain, she felt beautiful once it was done, Bouglada said. She was very proud of her stars on her cheeks. Her eldest sister had been tattooed before her and she wanted to imitate her. Bouglada said she has now given away all her silver jewellery to atone for the sin that believers told her she had committed by being tattooed. (Photo by Zohra Bensemra/Reuters)

A female Kurdistan Workers Party (PKK) fighter stands near a security position in Sinjar, March 13, 2015. Women fighters at a Kurdistan Workers Party (PKK) base on Mount Sinjar in northwest Iraq, just like their male counterparts, have to be ready for action at any time. Smoke from the front line, marking their battle against Islamic State, which launched an assault on northern Iraq last summer, is visible from the base. Many of the women have cut links with their families back home; the fighters come from all corners of the Kurdish region. (Photo by Asmaa Waguih /Reuters)