Comparison of calcite crystallographic texture in the shells of the Rhynchonelliform brachiopod, Terebratulina retusa and the bivalve mollusc, Mytilus edulis

Citation

Cusack M, Pérez-Huerta A, Dalbeck P, Chung P & Lee MR (2008) Comparison of calcite crystallographic texture in the shells of the Rhynchonelliform brachiopod, Terebratulina retusa and the bivalve mollusc, Mytilus edulis. In: Rollett A (ed.) Applications of Texture Analysis. Ceramic Transactions, 201. Hoboken, NJ, USA: John Wiley & Sons, pp. 587-593. http://onlinelibrary.wiley.com/doi/10.1002/9780470444214.ch64/summary; https://doi.org/10.1002/9780470444214.ch64

Abstract
Living systems exert exquisite control on all aspects of biomineral formation, determining the morphology, mineralogy, crystallography and even the mineral polymorph. Aspects of this biological control can be seen in the resultant pronounced crystallographic textures. Here we use electron backscatter diffraction (EBSD) to compare the calcite crystallographic orientation and texture in the shells of the Rhynchonelliform brachiopod, Terebratulina retusa with that of the calcite of the bimineralic shell of the bivalve mollusc, Mytilus edulis. Despite different evolutionary histories, calcite of T. retusa and M. edulis has the same trend in crystallographic orientation through ontogeny. M. edulis calcite has a much stronger crystallographic texture than that of T. retusa. This may be a requirement of a bimineralic shell where the interface between the two calcium carbonate polymorphs; calcite and aragonite, must be controlled.

Keywords
Calcite; aragonite layer; crystallographic texture; rhynchonelliform brachiopod; bivalve molluscs