Photomosaic® by Robert Silvers;  Original photography by Matthew Spiegelman

To capture the full array of human variation, Georgia Dunston, a geneticist at Howard University in Washington, D.C., leads studies of common diseases such as prostate cancer and hypertension among people of African descent. “There’s knowledge inherent in these diseases, and we can unravel it if we can bring the right thinking to it,” she says. This portrait of Dunston is made up of faces spanning the continuum of human physical appearance.