Credit: Colleen Kelley/University of Cincinnati Popular in aquariums all over the world, the zebrafish is native to South Asia. But here in a Cincinnati Children's Hospital Medical Center's laboratory, the freshwater variant plays a vital role in scientific discovery. The iconic stripes are eye-catching but it's the transparency of zebrafish embryonic tissue which are most prized by researchers like Oriana Zinani, a fifth-year doctoral student in molecular developmental biology in the University of Cincinnati College of Medicine. The patterning of the zebrafish's spine gives the appearance of stripes; it is controlled by segmentation genes which function like a clock.