In situ differentiation of iridophore crystallotypes underlies zebrafish stripe patterning

The skin of zebrafish is patterned by alternating blue stripes and yellow interstripes which arises from guanine crystal-containing cells called iridophores that reflect light. Here the authors track iridophores and see that they do not migrate between stripes and interstripes, but instead differentiate and proliferate in place based on their micro-environment.