This sculpture made of purple and clear glass beads depicts bacteriophage φX174, a virus that infects bacteria. It rests on a surface that portrays an adaptive landscape, a conceptual visualization. The ridges represent the gene combinations associated with the greatest fitness levels of the virus, as measured by how quickly the virus can reproduce itself. φX174 is an important model system for studies of viral evolution because its genome can readily be sequenced as it evolves under defined laboratory conditions. Courtesy of Holly Wichman, an evolutionary biologist at the University of Idaho. (Sculpture by Wichman; surface by A. Johnston, an undergraduate student in landscape architecture; and photo by J. Palmersheim.)