In laboratories at the University of Oregon, scientists have reached 160 million years into the past to resurrect proteins from the earliest mammals — and some of these ancient molecules kill bacteria more effectively than the drugs we rely on today. The work centers on lactoferrin, an immune protein carried in breast milk and tears, and the antimicrobial peptide hidden within it that ruptures bacterial cell walls. By tracing the evolutionary history of this protein back to the common ancestor of all placental mammals, researchers are not merely studying the past — they are reading nature's lo