A masked reveller parades through the streets on the first day of the carnival season in Lucerne, Switzerland, 12 February 2015. In the background the well known Kappellbruecke bridge. (Photo by Alexandra Wey/EPA)

A woman takes a selfie in front of a Lunar New Year display featuring sheep at a shopping mall in Hong Kong, February 13, 2015. (Photo by Bobby Yip/Reuters)

Tourists take pictures of straw figurines of traditional deities Shennong (R) and Zhang Wulang (L back) during China's National Day Holiday, in Xinhua county, Hunan province, October 4, 2015. (Photo by Reuters/China Daily)

Nazi dictator Adolf Hitler greets supporters at a May Day gathering in the Olympic Stadium, Berlin. (Photo by Keystone). 1st May 1938

Afghanistan, published by Taschen later July, is a retrospective portfolio of the Magnum photographer Steve McCurry’s most striking images of the country, from 1979 to 2016. Here: Kunar province, 1980. Armed mujahideen carry animal skins to use as inflatable buoys to cross rapids. (Photo by Steve McCurry/Taschen/Magnum Photos/The Guardian)

This Thursday, January 22, 2015 photo made with a long exposure shows the glow from a Noctiluca scintillans algal bloom along the seashore in Hong Kong. The luminescence, also called Sea Sparkle, is triggered by farm pollution that can be devastating to marine life and local fisheries, according to University of Georgia oceanographer Samantha Joye. Noctiluca itself does not produce neurotoxins like other similar organisms do. But its role as both prey and predator tends can eventually magnify the accumulation of toxins in the food chain, according to R. Eugene Turner at Louisiana State University. (Photo by Kin Cheung/AP Photo)

A roadside currency exchange vendor sorts Indian currency notes at his stall in Agartala, India, December 6, 2016. (Photo by Jayanta Dey/Reuters)