From CT scans of embedded Ivanovia to models using rapid prototyping

A limestone cube from Tunisia with embedded thalli of the Permian, coenocytic, cyathiform green alga, Ivanovia tebagaensis , was CT (computed tomography) scanned as a nondestructive method to study some of its morphological features. Two sets of scans were used to make three physical three-dimensional models of Ivanovia structures by rapid prototyping stereolithography or layer manufacturing: (1) an asexual reproductive bud using the initial medical CT scans; (2) a cyathiform thallus with an attached bud and a second cup fused to the bottom of the first; and (3) about ten per cent of the total rock volume. A set of high resolution scans was used to construct (2) and (3). Study of the models suggested new information on developmental stages of budding and the great extent of membrane connections.