Architectonics of Metazoa as the Basis for the Reconstruction of the Ontogeny and Phylogeny of Extinct Taxa

Abstract

Architectonics is the study of the division of the animal body into modular structures that are to some extent autonomous in their ontogeny and phylogeny. Thereby it allows key points in the ontogeny of many fossil taxa to be identified. Studying the symmetry of the mutual arrangement of the modular structures of the organism and its evolution, together with the analysis of architectonics, promorphology helps to clarify the evolution of ontogeny in real geological time and thereby brings together paleontology and developmental biology. The application of this approach to echinoderms enables the presence of a torsion process in the ontogeny of all Pelmatozoa and Soluta (among Carpozoa), and the absence of this process in Stylophora, to be demonstrated. The analysis of architectonics and promorphology of Paleozoic tetracorals (Rugosa) revealed the correlation of the oral-aboral and dorsal-ventral axes of their larvae with the oral-aboral and directive axes of the polyp developing from them. This shows that the bilateral symmetry of Anthozoa and possibly of all Cnidaria preceded their radial symmetry.