In 1878 Sir Francis Galton, Charles Darwin's cousin and the father of Eugenics, introduced a new technique he called "Composite Portraiture." It can be an amusing creative trick to play with (as seen in Archie Bishop's 2002 composite of six Hunter College Students, below) but its history became inextricably intertwined with ideas of innate human inequality and with calculated strategies for identifying and then eliminating "undesirable" groups of people from the human gene pool.
Employing a system of multiple exposure, he merged photographic portraits of individuals into generic faces. While Galton's invention was first promoted as a novel artistic device, he soon maintained that his composite photography was a "scientific tool" that could hide the particular characteristics of individuals and reveal the hereditary attributes or deficiencies of the TYPE they belonged to.
Galton maintained that the photographic portraits of ideal types (Jews, criminals, members of the Royal Guard, tubercular women, etc.) could be used to identify those portions of humanity which should be selected for surgical sterilization, in order to extinguish the bloodlines of degeneration, criminality, feeble-mindedness and evil from among the human race.
In the United States, as the Second International Congress on Eugenics was held at the American Museum of Natural History in 1921, composite portraits were among the various exhibits designed to illustrate the characteristics of those peoples whose genetic make-up threatened to pollute America's "original Nordic stock" through interbreeding. The Johnson-Reed Act (1924) that closed off immigration, and the Buck v. Bell Case that led the Supreme Court to uphold forced sterilization as the law of the land, were two sequelae that emanated from the 1921 Congress.