Three Chinese soldiers at the time of a civil war in China. (Photo by General Photographic Agency/Getty Images). 1922

A man irrigating a rice paddy field using a traditional method. (Photo by Fox Photos/Getty Images). Japan, circa 1938

A construction worker sweeps up as the final touches are completed on “Comedy Carpet” by British artist Gordon Young, the latest art installation on Blackpool's promenade on October 7, 2011 in Blackpool, England. (Photo by Christopher Furlong/Getty Images)

“The banker”. Underwater Sculpture, Museo Subacuático de Arte, Cancun. (Photo by Jason deCaires Taylor/UnderwaterSculpture)

Women in costumes walk as they participate in Halloween celebrations in the downtown of Seoul, South Korea, October 31, 2015. (Photo by Kim Hong-Ji/Reuters)

Russian riot policemen beat young PREGNANT female anti-Putin activist during a protest rally against the Presidential inauguration of Vladimir Putin on May 6, 2012 in Moscow, Russia.

The tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away from Earth in the southern constellation Carina. (Photo by Reuters/NASA)

A keeper stands next to llamas during the Annual Stocktake at ZSL London Zoo in London, Britain February 7, 2018. (Photo by Tom Jacobs/Reuters)