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arXiv · 0708.1256

Eutacticity in sea urchin evolution

J. López-Sauceda·J. L. Aragón
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Abstract

An eutactic star, in a n-dimensional space, is a set of N vectors which can be viewed as the projection of N orthogonal vectors in a N-dimensional space. By adequately associating a star of vectors to a particular sea urchin we propose that a measure of the eutacticity of the star constitutes a measure of the regularity of the sea urchin. Then we study changes of regularity (eutacticity) in a macroevolutive and taxonomic level of sea urchins belonging to the Echinoidea Class. An analysis considering changes through geological time suggests a high degree of regularity in the shape of these organisms through their evolution. Rare deviations from regularity measured in Holasteroida order are discussed.

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BibTeXRIS

J. López-Sauceda, J. L. Aragón. 2007-08-09. Eutacticity in sea urchin evolution. https://doi.org/10.1007/s11538-007-9273-2

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