Cytophysiological basis of disruptive pigmentary patterns in the leopard frog Rana pipiens . I chromatophore densities and cytophysiology

Statistical analyses of chromatophore densities and morphological states in wild type, burnsi , and kandiyohi : adult Rana pipiens integument yielded the conclusion that disruptive pigmentary pattern is permanently defined by regional chromatophore densities. Spatial chromatophore patterning is enhanced and rendered more visible by the morphological and physiological differences among chromatophores within the various pattern regions. Specifically, (1) chromatophores were differentialy distributed among pattern regions, (2) greater complexity of gross disruptive patterning had greater underlying melanophores densities, (3) there were significant density differences among non‐sib individual animals, among fertilization, and among shipment batches, but not among full‐sibs, and (4) kandiyohi individuals had more while burnsi individuals had fewer total melanophores than wild type. A stellate morphology was significantly correlated with high melanophore density, although the relationship of melanophore density to melanophore morphology differed among pattern regions and among genotypes. The functional interrelationships of density and morphology, and their role in disruptive patterning and coloration, are discussed.