Public Space series, 2015. This series by Morteza Niknahad and Behnam Zakeri tends toward cinema, taking an almost cartoonish view of modern life in Iran. This work was inspired by the social life of dolphins. (Photo by Morteza Niknahad and Behnam Zakeri/The Guardian)

A cyclist drives past a flowering rapeseed field not far from the small Bavarian village of Schoengeising, near Munich, during a nice, warm sunny weather day on May 17, 2017. (Photo by Christof Stache/AFP Photo)

Men carrying a shrine jump over a bon fire, which means a wish for good luck during a traditional Chinese lunar new year celebration in Jieyang, Guangdong province, China, February 2, 2017. (Photo by Reuters/China Daily)

In this February 19, 2017 photo, a couple dances during the “If you don't give me....then you lend me” Carnival street party on Ipanema beach, in Rio de Janeiro, Brazil. The typical view of Carnival in Brazil is anything goes, with no headdress too big, no outfit too small, no song too ribald, but this year some organizers of the world's best known party are drawing the line at lyrics that are sexist, homophobic or racist. (Photo by Silvia Izquierdo/AP Photo)

A US Marine leads two Viet Cong suspects in restraints during the Tet Offensive on February 20, 1967. (Photo by Bettmann Archive/Getty Images)

Open jaws of a Great White Shark Carcharodon Carcharias, South Africa. (Photo by Stephen Frink Collection/Alamy Stock Photo)

Chinese model Ming Xi falls down on runway during the 2017 Victoria's Secret Fashion Show at Mercedes-Benz Arena on November 20, 2017 in Shanghai, China. (Photo by VCG/VCG via Getty Images)

Performers Roni, Liv and Becky behind the scenes at Great Yarmouth Hippodrome Circus, England. (Photo by Nick Warner/The Guardian)