A young arab boy, armed with a rifle and a knife, in the Aden Protectorate near Yemen. (Photo by Richards/Fox Photos/Getty Images). February 1938

A young exhibitor arrives with her kitten on a lead at the National Cat Club show at Crystal Palace, London. (Photo by Fox Photos/Getty Images). 2nd December 1931

Waura Indians wrestle during this year's “quarup”, a ritual held over several days to honour in death a person of great importance to them, in Xingu National Park, Mato Grosso State, Brazil August 25, 2013. (Photo by Ueslei Marcelino/Reuters)

Soldiers, including two recruits who have brought some chickens, at Victoria prepare to board the train for the battle front. (Photo by Hulton Archive/Getty Images)

Visitors of the world's longest tree top walk between the trees of the Bavarian forest on November 6, 2009 in Neuschoenau, Germany. The path, 1300 meters long and in 8 to 25m height, winds up to an impressive tower with a height of 44 meters. The wooden construction is integrated into the forest and delivers a natural experience. (Photo by Miguel Villagran/Getty Images)

Rene Penia drives his VW Beetle 1995, locally called “Vocho”, through the streets of Monterrey April 22, 2015. The car was painted by a local artist to be part of an exhibition on the 1960s at the National History Museum in Monterrey where it was on display for five years. Pena bought the car for 25.000 Mexican Pesos (some USD 2,000 at that time) in 2013 during an auction and he then converted the car into an electrical vehicle. (Photo by Daniel Becerril/Reuters)

Australian World War Two veterans place crosses and flags at graves before attending the French-British ceremony at the British War cemetery in Bayeux, June 6, 2014. REUTERS/Leon Neal/Pool