“Don't Leave Any Food On Your Plate”. The giraffes at Nairobi's Giraffe Manor are totally at home with humans. They will eat out of your hand, or even off your plate. Photo location: Giraffe Manor, Nairobi, Kenya. (Photo and caption by Gavin Werbeloff/National Geographic Photo Contest)

Smithfield meat porters march on the Home Office, bearing a petition which calls for an end to all immigration into Britain, 25th August 1972. (Photo by Keystone/Hulton Archive/Getty Images)

A participant, riding a horse and dressed as a knight, presents flowers to women during an event marking Valentine's Day in central Moscow, Russia, February 14, 2016. (Photo by Maxim Zmeyev/Reuters)

People walk along a street with long-tailed macaques in Lopburi, north of Bangkok November 29, 2015. (Photo by Jorge Silva/Reuters)

A girl runs from waves crashing over the promenade on December 24, 2015 in Blackpool, England. The Met Office is warning of 80mph winds and torrential downpours over the Christmas holidays, as dozens of flood alerts are issued for already devastated regions. (Photo by Nigel Roddis/Getty Images)

Valery Bystritskii, 10, gets a fellow student into a lock at Bunny's Gym in July 2015 in Winchester, Tennessee. (Photo by Mike Saliba/Barcroft USA)

North Korean children wave to people on a Chinese tourist boat on the banks of Yalu River near the Chongsong county of North Korea, opposite the Chinese border city of Dandong, May 8, 2011. (Photo by Jacky Chen/Reuters)

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