The Evolution Of Biomineralization In Metazoans

The Fifth International Biomineralization Symposium was held in May 1986 at The University of Texas at Arlington, Arlington, Texas. The chosen theme was the origin, evolution and modern aspects of biomineralization in plants and animals. Thus, the symposium was designed to bring together experts in ocean and atmospheric chemistry, geochemistry, paleontology, biology, medicine and related fields to share accumulated knowledge and to broaden research horizons. The contents of this volume reflect the diversified interests and views of contributors from these fields. Topics range from contrasting views of the origin of ocean chemistry, the cause or causes for the biomineralization among plants and animals, the evolution of style and structure of biomineralization, and the role of inorganic and organic compounds in biomineraliza tion. It was clear from those gathered in Arlington that the efforts of all researchers in any aspect of biomineralization can be strengthened and extended by greater exposure to the work of others in allied fields. At the time of this printing, several collaborative efforts have grown from interest and contacts developed during the symposium. Rex E. Crick viii ACKNOWLEDGEMENTS The symposium would not have occurred with the financial support of The Organized Research Fund of The University of Texas at Arlington and The Sea Grant Program administered by Texas A & M University. The staff of the Department of Geology of The University of Texas at Arlington were largely responsible for providing a pleasant atmosphere for learning.

Several years ago, we realized that the most prominent ideas that had been ex pressed about the origin and early evolution of the Metazoa seemed to have been developed chiefly by zoologists using evidence from modern species without reference to the fossil record. Paleontologists had, in fact, put forth their own ideas but the zoological and the paleontological evidence were about the problem, seldom considered together, especially by zoologists. We believed that the paleon tological documentation of the first Metazoa was too scattered, too obscure to Western readers, and much of it too recent to have been readily available to our colleagues in zoology. Whether or not that was entirely true, we thought that a single volume reviewing the fossil record of the earliest Metazoa would be useful to many in both paleontology and zoology, especially since so much new informa tion has been developed in the last few years. Some of this information has been summarized in general articles recently, but an overview of most of the field does not exist. We therefore organized this book in five parts so that the evidence could be placed in perspective and summarized and inferences made from it. Part I intro duces the previous hypotheses that have been proposed for the origin and early radiation of Metazoa. Part II consists of two summary chapters that set the sedi mentological, geochemical, and biological background to the known radiations of Metazoa.

This book should be of interest to teachers, students and researchers in paleontology, biology, evolutionary biology, zoology and cell biology.

Analyzing animal development in a comparative framework provides a unique window into evolutionary history. With a long tradition that dates back to iconic 19th-century zoologists such as Ernst Haeckel and Charles Darwin, Evolutionary Developmental Biology is firmly rooted in morphological research. While studies using a classical model system approach have resulted in considerable methodological progress, in particular by establishing molecular genetic tools to tackle questions surrounding animal development, it quickly became obvious that a broad comparative dataset involving as many taxa as possible is necessary for sound evolutionary inferences. Thus, today’s EvoDevo embraces morphological, molecular, and experimental procedures, interpreted in a phylogenetic framework, in order to answer key questions that revolve around the evolution of animal cell types, organ systems, and, ultimately, entire species.

The interplay between Geology and Biology has shaped the Earth from the early Precambrian, 4 billion years ago. Moving beyond the borders of the classical core disciplines, Geobiology strives to identify chains of cause-and-effect and synergisms between the geo- and the biospheres that have been driving the evolution of life in modern and ancient environments. Combining modern methods, geobiological information can be extracted not only from visible remains of organisms, but also from organic molecules, rock fabrics, minerals, isotopes and other tracers. An understanding of these processes and their signatures reveals enormous applied potentials with respect to issues of environment protection, public health, energy and resource management. The Encyclopedia of Geobiology has been designed to act as a key reference for students, researchers, teachers, and the informed public and to provide basic, but comprehensible knowledge on this rapidly expanding discipline that sits at the interface between modern geo- and biosciences.