A stained-glass spiral of cells from an aloe plant, an old-growth forest of neural cells in the retina of a mouse, a starry sea of leaf hairs on a garden shrub—organisms have a way of reinventing themselves rather spectacularly under the microscope, giving observers a new appreciation for what Charles Darwin termed nature's “endless forms most beautiful.” In these tiny worlds, beauty arises from both the brilliance of evolution's small-scale solutions to life's challenges and the techniques microscopists use to visualize biological structures and processes. To peer through the eyepiece is to discover a universe in an embryo, an organ, a cell. As Igor Siwanowicz of the Howard Hughes Medical Institute [see photographs on pages 61 and 63] puts it, “microscopy allows me to see beyond the cuticle, explore the baroque arrangement of muscle fibers or intricate fractal-like network of neurons, and appreciate that beauty (probably in the most subjective sense possible) isn't only skin deep.” Siwanowicz is among the winners of the 2012 Olympus BioScapes International Digital Imaging Competition, which welcomes entries from scientists and hobbyists alike. His images and other entries that caught Scientific American's eye grace the pages that follow. We hope you enjoy this armchair safari into miniature realms where science and art converge.