Soldier boys at Fort Dix, N.J., learn something about guns during their working hours, as they show their girlfriends at a camp dance, December 13, 1940. In front row, playing with the coin amusement gun, from left: Pvt. Tom D'Amato of West Orange; Rose Sinkewicz, behind gun site, of Trenton; Julia Ivans of Trenton, and Pvt. Vernon Landers of Kearney. Back row: Pvts. William Sargent and William Corlies of Philadelphia. (Photo by AP Photo)

Indian artists dress up as the Hindu deity “Hanuman” – the monkey God in Hindu mythology – to mark the Rama Navami festival in Bangalore on March 25, 2018. Rama Navami is a spring Hindu festival that celebrates the birthday of the deity Rama. He is particularly important to the Vaishnavism tradition of Hinduism, as the seventh avatar of Vishnu. (Photo by Manjunath Kiran/AFP Photo)

An ethnic Lisu man dances barefoot on hot charcoal embers to celebrate the annual Knife Pole Festival in Luzhang township of Nujiang Lisu Autonomous Prefecture in Yunnan province, China, March 29, 2018. (Photo by Aly Song/Reuters)

Honorable Mention: “The Storm”. During I was taking photo with my nephew, the storm came and I caught this beautiful moment. Photo location: Kocaeli, Turkey. (Photo and caption by Aytül Akbaş/National Geographic Photo Contest)

David Pena poses for a photograph with his Lada 2101 built in 1979 on a street in Havana February 9, 2015. Getting parts from the United States is cheaper than in Cuba, where state-run stores sell them at four times the cost, said Pena, a mechanic and president of the Russian Car Club in Havana who drives a souped-up, sporty red 1972 Lada 2101 that he fixed himself. His own Lada has a Fiat engine and an extra Alfa Romeo carburetor. (Photo by Enrique De La Osa/Reuters)

Ty, a 15-year-old boy, poses for a picture while collecting usable items at a landfill dumpsite outside Siem Reap March 19, 2015. Ty, who finished six-grade primary school, said he makes 5 USD per month working at the dumpsite. (Photo by Athit Perawongmetha/Reuters)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)

Masked youths face off with French police and gendarmes during a demonstration in Paris as part of nationwide protests against plans to reform French labour laws, France, June 14, 2016. (Photo by Willi Effenberger/Pacific Press/SIPA Press)