FaceResearch.org, a site run by two psychologists at the University of Aberdeen in Scotland, features software that can average together faces from thousands of photos. These images purportedly show the average face of women from 40 different nationalities.

Tsar Alexander II (1818–1881) known as “The Liberator” lying in state. He was mortally wounded by an assassination attack in St Petersburg. (Photo by Hulton Archive/Getty Images). March 1881

Two guards perform an execution in China, one holding the gun, the other holding a mask over the victim's face. (Photo by General Photographic Agency/Getty Images). Circa 1925

The internet has been awash with face swaps for years — here’s our contribution to the art of creating nightmares with Photoshop.

Workers use a boat to recover supplies from a flooded grain elevator May 4, 2011 in Caruthersville, Missouri. Heavy rains have left the ground saturated, rivers swollen, and has caused widespread flooding in Missouri, Illinois, Kentucky and Arkansas. (Photo by Scott Olson/Getty Images)

Nelson Mandela make up complete. 40-year-old London-based makeup artist, Maria Malone-Guerbaa has the ability to transform herself into any celebrity or creature using only her basic makeup essentials. Maria used only make up and face paints to create the illusion of Nelson Mandela, Britain's Queen Elizabeth II, and many other A-list celebrities. (Photo by Maria Malone-Guerbaa/Rex Features USA)

A talented artist has created breathtaking intimate portraits by using detailed maps of the world as his canvas. Cardiff-based illustrator, Ed Fairburn, combines the patchwork of roads, terrains and rivers to for his unique sketches. Photo: Ink on a 1977 road map of Germany. (Photo by Ed Fairburn/Rex Features)