Leo Peichl is a comparative retinal neurobiologist. He has studied the image-processing nerve cells in the retina of the eyes of many mammalian species — from whales to lemurs, mole-rats, and bats. One focus of his work is the study of photoreceptors — the cones and rods — and their role in color vision, which differs between species. For example, he and his colleagues found that whales and seals cannot see colors, whereas nocturnal bats, long believed to be color-blind, actually possess the photoreceptor equipment needed to see colors, including ultraviolet. He and his collaborators have published their findings in approximately 120 articles in scientific journals and books. After obtaining a master’s degree in physics, Leo earned a Ph.D. in neurobiology at the University of Constance (Germany), where he became fascinated with exploring the retina. He continued these studies as a postdoctoral researcher at King’s College London and at the Friedrich Miescher Laboratory of the Max Planck Society in Tübingen. He then worked as a research group leader at the Max Planck Institute for Brain Research in Frankfurt/Main until his retirement in 2015. After retiring, he was a guest researcher in the Anatomy Department of Frankfurt University Medical School until 2025. Leo is also an adjunct professor in the Biosciences Department of Frankfurt University, where he teaches neurobiology, and he regularly gives lectures at high schools to inspire young people to pursue neuroscience.