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Meeting Abstract
A defining morphological characteristic of coleoid cephalopods is skin embedded with an array of chromatophores: dynamic, colored neuromuscular organs. At the core of each chromatophore is an expandable sacculus of numerous minute granules containing ommochrome pigments. We have found using electron microscopy and quantitative image analysis that each color class of Doryteuthis pealeii chromatophore contains distinct assemblages of granules with characteristic size, shape, and external rugosity: brown granules are large, ellipsoidal, and smooth; reds are mid-sized and ring-shaped or grooved; yellows are small, spherical, and fine-grained. The distinctive internal and external morphologies of the granule color classes suggest structural coloration mechanisms that may complement the pigmentary mechanisms for coherent and efficient color production from each color class of chromatophore. Future modeling of these biophotonic interactions is now possible with these new data. This work was funded by AFOSR grant A9550-09-0346 to RTH and NSF-REU grant DBI-1359230 to MBL. We would like to thank Karen Crawford, Kyle Fisk, Kyle Ford, Richard Gates, Kasia Hammar, Louis Kerr, James Kutlowski, Alan Kuzirian, and Lydia Mäthger.