Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

“Kilauea Rules”. The most extreme place we put ours kayakers to paddle till now. Photo location: Big Island, Hawaii. (Photo and caption by Alexandre Socci/National Geographic Photo Contest)

Participants take part in a high-heel race at a Gay Pride party in the central neighborhood of Chueca in Madrid on July 3, 2014. (Photo by Gerard Julien/AFP Photo)

Gertrude “Billie” Murphy, 22, is brought in for questioning in the murder case of Michael Stopec, who was shot and killed in an apartment hotel, circa July 1927. Murphy had been friends of the married Stopec and his suspected killer Henry Guardino, 31. It is said that Stopec and Guardino were “bitter rivals for the favor of Billie” and that Murphy had tired of Guardino and was going to stay with Stopec. Murphy was also married to a man in the Joliet penitentiary. (Photo by Chicago Herald & Examiner Historical Photo)

Tsewang Dolma, 33, a farmer and housewife poses for a photograph in Matho, a village nestled high in the Indian Himalayas, India September 29, 2016. When asked how living in the world's fastest growing major economy had affected life, Dolma replied: “Our culture is spoiled now. We don't wear our traditional dress”. (Photo by Cathal McNaughton/Reuters)

Comandos de Salvamento rescuers Maria Martinez (L) and Ana Chichilla attend to a wounded homeless man in San Salvador, El Salvador July 16, 2016. The man was attacked with a machete by suspected gang members. In 2015, El Salvador registered a record 103 homicides per 100,000 habitants, making it one of the most dangerous countries in the world outside a war zone. But for many young people who have few chances to distance themselves from rivalries between so-called maras in their schools and neighbourhoods, a civil-society organisation called the Comandos de Salvamento, or Rescue Corps, has been a refuge. (Photo by Jose Cabezas/Reuters)

A leaflet denouncing South Korean President Park Geun-hye lies on the ground after it was torn at a protest calling Park to step down, in Seoul, South Korea, November 19, 2016. (Photo by Kim Hong-Ji/Reuters)

A Vietnamese bride is seen pushing the groom on a scooter during a photo shoot for their wedding in An Bang Beach outside Hoi An in Vietnam December 11, 2016. (Photo by Reuters/Stringer)