Zebrafish are extensively used as model organism by biologists. Researchers have wondered how their dark blue and bright yellow stripes develop. It is known that the stripes originate from the interplay between black melanophores, yellow xanthophores, and silvery iridophores – three types of pigment cells. Interestingly, there is no prepattern that the pigment cells follow; rather the stripes develop due to the interaction of the pigment cells. Alexandria Volkening, a graduate student from Brown University’s Division of Applied Mathematics and the lead author, devised a model that treated cells as individual agents and studied their interaction with each other. According to this mathematical model \u201ctwo dynamic processes–the movement of pigment cells across the skin, and the birth and death of cells as the fish grows–combine to develop zebrafish stripes.\u201d It was found that without either of the two processes, the stripes could not develop appropriately. This research can further our understanding of how complex patterns and structures form in the nature.<\/p>\n