In this Thursday, December 1, 2016 photo, Cat Bigney, part of the Oglala Native American tribe, waits on the shore of the Cannonball river for travelers to arrive by canoe at the Oceti Sakowin camp where people have gathered to protest the Dakota Access oil pipeline in Cannon Ball, N.D. So far, those at the camp have shrugged off the heavy snow, icy winds and frigid temperatures. But if they defy next week's government deadline to abandon the camp, demonstrators know the real deep freeze lies ahead. Life-threatening wind chills and towering snow drifts could mean the greatest challenge is simple survival. (Photo by David Goldman/AP Photo)

A girl rides a donkey as another walks by at the Shawqaba camp for internally displaced people who were forced to leave their villages by the war in Yemen's northwestern province of Hajjah March 12, 2016. In northwest Yemen, one of the poorest countries in the Middle East, about 400 families uprooted by the war have been stuck in the Shawqaba camp in Hajjah province for the past year. Residents live in poorly built huts that protect them neither from summer heat nor winter cold in a camp that lacks the most basic services. (Photo by Abduljabbar Zeyad/Reuters)

A humanoid robot named Kansei, meaning “sensibility” in Japanese, makes a facial expression depicting “happiness”, next to the word “Love” during a demonstration at a laboratory of Meiji University's Robot and Science Institute in Kawasaki, south of Tokyo in this June 4, 2007 file photo. Three-fourths of robot installations over the next decade are expected to be concentrated in four areas: transportation equipment, including the automotive sector; computer and electronic products; electrical equipment and machinery. Labor costs have climbed in countries such as China that have been popular for outsourcing production, while technological advances for robots allow them to be more flexible and perform more tasks. (Photo by Yuriko Nakao/Reuters)

Intrigued by photographing time, Singapore-based photographer Fong Qi Wei created single, composite pictures from a sequence of images spanning 2-4 hours. He concentrated on capturing sunrises and sunsets as they evolved over different landscapes, seascapes, and cityscapes. He then digitally stitched the images together to get a snapshot of time passing over the scene for his series “Time is a Dimension”. “Most paintings and photographs are an instance of time”, Wei explained in his artist’s statement. “That’s not the way the world works. We experience a sequence of time, and that’s why a video is somehow more compelling than a freeze frame”. (Photo by Fong Qi Wei/Thoughtful Photography)

It is already one of the world’s most iconic cities, but this incredible collection shows how much Paris has changed over the course of the past century. The collection, by French photographer Julien Knez, shows Paris in the 1940s against a backdrop of how the same places look today. Knez says he put the striking collection together to celebrate the 71st anniversary of the city’s liberation from Nazi control in August 1944. Here: Soldiers outside the Hotel De Ville in the 1940s. (Photo by Julien Knez/Caters News)

“Grit and Glamour”, a retrospective of the late British photographer Elsbeth Juda, who fled Nazi occupation and came to England in 1933, is at the Jewish Museum, in London, until July 1, 2018. Here: Shelagh Wilson, Copacabana beach, Rio de Janeiro, 1951. (Photo by Elsbeth Juda Archive/Victoria and Albert Museum)

Models of Cold War-era Allied (L) and Soviet Bloc weaponry face one another at the new Bundeswehr Military History Museum (Militaerhistorisches Museum der Bundeswehr, or MHM) on October 11, 2011 in Dresden, Germany. The museum, redesigned by star architect Daniel Libeskind, traces Germany military history from 1300 to the present, including during the Nazi period and the Cold War, and also examines the influence of the military on popular culture. (Photo by Sean Gallup/Getty Images)

The “Yama” (Pit) memorial is seen in the centre of Minsk May 5, 2015. The memorial is dedicated of the destruction of the Minsk ghetto during World War Two, when several hundred thousands of Jews were slaughtered. Belarus will mark Victory Day on May 9, the 70th anniversary of the Soviet Union's victory over Nazi Germany. (Photo by Vasily Fedosenko/Reuters)