A Taiwanese woman takes a photo of a Christmas tree decoration at a street in Taipei, Taiwan,13 December 2015. (Photo by Ritchie B. Tongo/EPA)

Bull riders prepare prior to a bull riding event in Santa Tecla, El Salvador, December 15, 2016. (Photo by Jose Cabezas/Reuters)

A woman from the Tarahumara ethnic group cuts firewood with an ax while preparing for winter in Caborachi village, in Guachochi, Mexico, December 17, 2016. (Photo by Jose Luis Gonzalez/Reuters)

Photographers help a Rohingya refugee to climb out of Naf River as they cross the Myanmar-Bangladesh border in Palong Khali, near Cox's Bazar, Bangladesh on November 1, 2017. (Photo by Hannah McKay/Reuters)

Female female male threesome. My bit on the side is my best male friend. (Photo by Laoshi/Getty Images)

Seven month old Christine Joy shares her pram with two 5 week old Gunsure Golden Cherry's cocker spaniel pups from Gunsure Kennels in Ashford, Middlesex. 22nd May 1953. (Photo by Fred Morley/Fox Photos)

Two sailors from HMS Fury enjoy a smoke with two women in bathing suits on a beach in Jersey, where their ship is on a visit. (Photo by William Vanderson/Fox Photos/Getty Images). 29th June 1935

Winner. “I took this vertical image in the Quarry Bay district of Hong Kong during the dusk ‘blue hour’, when there was a perfect balance between the ambient light in the sky and the artificial lights of the high-rise residential buildings”. (Photo by Jatinder Heer/The Guardian)