Tank crew standing in front of M-4 tank, Ft. Knox, Kentucky, June, 1942. (Alfred Palmer/OWI/LOC)

In this December 23, 2013 photo, Indian army soldiers patrol near one of their forward post at the Line of Control (LOC), that divides Kashmir between India and Pakistan, at Krishna Ghati (KG Sector) in Poonch, 290 kilometers (180 miles) from Jammu, India. The military commanders of longtime rivals India and Pakistan met on Tuesday in a bid to stop frequent cross-border attacks in disputed Kashmir which escalated tensions in the region in recent months. (Photo by Channi Anand/AP Photo)

Men stroll past roadside vendors as a painted truck makes its way through the busy street in Kabul, Afghanistan, November, 1961. (Photo by Henry S. Bradsher/AP Photo via The Atlantic)

Georgian men take a break from selling fruit and vegetable at a street market in Tbilisi, Georgia, Wednesday, July 20, 2016. (Photo by Shakh Aivazov/AP Photo)

A weeping South Vietnamese mother and her three children are shown on the deck of this amphibious command ship being plucked out of Saigon by U.S. Marine helicopters in Vietnam, April 29, 1975. (Photo by AP Photo)

A suspected Vietcong is kicked by a Vietnamese soldier holding a rifle as another soldier attempts to tie his hands on October 22, 1965. The prisoner was one of 15 captured October 21 near Xom Chua when government troops raided in the plain of reeds area. Troops killed 43 suspected Vietcong and seized some arms. (Photo by Richard Merron/AP Photo)

Dancers from the Tareikura Academy dance on stage during The Power Of Inclusion Summit 2019 at Aotea Centre on October 03, 2019 in Auckland, New Zealand. The Power of Inclusion is a global summit where international and local voices share their stories, experiences and expertise to generate momentum for a future where representation and inclusion are the new screen industry standards. The Power of Inclusion summit is hosted by New Zealand Film Commission and Women in Film and Television International, with support from The Walt Disney Studios. (Photo by Michael Bradley/Getty Images for New Zealand Film Commission)

“Two Brothers”. We found about 20 lions eating a buffalo. When the male leaved the group we anticipated him to take photos. It is 8AM, light is perfect and the position too. The lion stops and looks down from the hill, another lion is coming up, it stiffens, I think that will be a fight, i'm tense, the camera is OK, the shots previously made perfect. The two meet, looking directly into their eyes, they sniff, rub against their heads, the tension drops, they start walking with the same step as when they were puppies, they are two brothers. Photo location: Masai Mara, Kenya. (Photo and caption by Massimo Mei/National Geographic Photo Contest)