In 1872, with the publication of “The Expression of the Emotions in Man and Animals,” Charles Darwin went rogue. Only a decade after the anatomist Duchenne de Boulogne’s produced the first neurology text illustrated by photographs, Darwin claimed to be the first to use photographs in a scientific publication to actually document the expressive spectrum of the face. Combining speculation about raised eyebrows and flushed skin with vile commentary about mental illness, he famously logged diagrams of facial musculature, along with drawings of sulky chimpanzees and photographs of weeping infants, to create a study that spanned species, temperament, age, and gender.