Fossils are essential to the reconstruction of the evolution of life and episodes in Earth history. Fossil skeletal material serves as the repository of chemical data widely used in the reconstruction of the Earth's climate-ocean system at various time scales. Knowledge of biomineralizationthe processes associated with the formation of mineralized biological structuresis essential to properly evaluate data derived from fossils. Additionally, knowledge of biomineralization is critical to the understanding of major events in the evolution of faunas, such as the original appearance of skeletons and some major extinction events. This is the first book to concentrate on aspects of biomineralization through Earth history. The book emphasizes skeletal formation and fossilization in a geologic framework in order to understand evolution, relationships between fossil groups, and the use of biomineral materials as geochemical proxies for understanding ancient oceans and climates. Approaching the subject from this viewpoint allows the authors to link the biotic, physical, and chemical realms. The focus is on shells and skeletons of calcareous organisms, although the broader impacts of these processes on other elements are also addressed, especially their roles in the global chemical cycles of carbon and silicon. The book explores the fine structures and mode of growth of the characteristic crystalline units, taking advantage of the most recent physical methodological advances. It is richly illustrated and will be of great interest to advanced students and researchers in paleontology, Earth history, evolution, sedimentary geology, geochemistry, and materials science.

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All well-dated occurrences of Upper Devonian septate corals (subclass Rugosa) are analyzed at species and higher taxonomic levels. Platform-dwelling corals are differentiated from the less numerous basin-dwelling corals.Through early and middle Frasnian time, evolution outpaced the extinction of rugose corals, so that late Frasnian faunas were more diverse than the earliest Frasnian faunas. This gradual increase of genera was terminated abruptly by an almost complete extinction of late Frasnian platform-dwelling Rugosa in uppermost gigas to lower Palmatolepis triangularis Zone time. None of the 151 species, and probably as few as two or three, at most five, of the 47 genera of late Frasnian shallow-water corals survived this event. The loss of coral biomass was equally devasting. Very few early Famennian platform-dwelling corals are known, although platform carbonates of this age were deposited in several regions. Platform faunas, comprising 66 species and 27 genera, reappeared in late Famennian time. These faunas were unrelated phylogenetically to known Frasnian faunas but were forerunners of shallow-water Carboniferous faunas.Basin-dwelling Rugosa were affected little by the late Frasnian extinction event: all 12 Frasnian genera survived it.Rugose coral data provide compelling evidence for a major late Frasnian extinction of shallow-marine benthos without suggesting a unique cause of it. The data are consistent with results expected of an asteroid impact or a rapid decline of ocean temperature, especially in regard to the very much higher survival rate among basin-dwelling corals. However, the data are not controlled by a sufficiently refined time scale to prove the geological instantaneity of such an event.

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