This collection of conference papers presents information on the molecular genetics, biomineralization, growth and ecology of extant brachiopod stocks (extrapolated back to the Cambrian), and the shell microstructure, taphonomy, paleogeography, evolution, and taxonomy of fossil brachiopods.

The growth history of a brachiopod is entombed in its shell, but research on fossil and living brachiopods has generated unanswered questions about these marine invertebrates. Several contributors to Brachiopods Past and Present comment on their differing structures and morphological detail. They use these as examples of ontogenetic and evolutionar

Published by the American Geophysical Union as part of the Antarctic Research Series, Volume 21. The Recent brachiopod faunas from southernmost South America, Antarctica, and the Subantarctic consisting of 21 genera and 37 species are described from new material. New taxa include the genera Manithyris and Bathynanus. Also new are 11 species: Compsothyris ballenyi, Hispanirhynchia? chiliensis, Manithyris rossi, Liothyrella multiporosa, Liothyrella scotti, Bathynanus tenuicostatus, Eucalathis macrorhynchus, Amphithyris hallettensis, Dallina eltanini, Fallax antarcticus, and Magellania? spinosa. Factor analysis was used to study relationships among morphological characters and environmental parameters. In Liothyrella, negative associations were found between beak height and water depth. The size of the pedicle opening within this genus is associated with the width of the hinge plate and the loop; apparently, these associations are related to increased dorsal adjustor muscle size with increased pedicle size. Similar relationships are found in the terebratellids, although here all of the characters are also negatively associated with water depth. Characters negatively associated with water depth may relate to the differing current strength at various depths. Puncta density is positively correlated with water temperature. Examples of brachiopod variation are discussed. Synonyms have resulted from former failure to study large samples and to appreciate the extent of brachiopod variation. A priori valuation of certain characters as being specific is unwarranted, since sibling species may be more similar than different subspecies of the same species. Many Recent and fossil brachiopod genera are too narrow in definition owing to oversplitting or to a narrow conception of monophyly. I advocate somewhat broader and more practical genera for obtaining the maximal information value from such taxa. Brachiopods, contrary to popular belief, are an abundant and viable group in the southern hemisphere faunas. Most brachiopods in the Ross Sea appear to have definite niches and habitats but may overlap geographically where population densities are low. Brachiopods here can be divided roughly into a slope and a shelf assemblage. The greatest species diversity occurs at the seaward edge of the Ross Sea shelf, interpreted as an ecotone effect where two different water types meet. Only South America and Antarctica appear to have or have had direct communication between some elements of their brachiopod faunas. Other similarities between separate southern continents are related to retention of common pre-Cenozoic elements or to chance dispersal of larvae across barriers. Events related to cooling during the late Pliocene or Pleistocene caused reduction of puncta density, shell thickness, and spiculation in the Recent fauna and apparently influenced the present species structure, at least in Liothyrella uva, Gyrothyris mawsoni, and Macandrevia.

Fossil species appear to persist morphologically unchanged for long intervals of geologic time, punctuated by short bursts of rapid change as explained by the Ecological Evolutionary Units (EEUs). Here, morphological variation in Paleozoic atrypide morphology at the subfamily level (Atrypinae and Variatrypinae) from the Silurian and Devonian time intervals in the third Paleozoic EEU (~444-359 my) were investigated using relatively new techniques of quantitative modeling. The study explains how a group of closely related taxa in atrypide subfamilies exhibit morphological conservation through time in P3 EEU within the Eastern North America region.

A monographic study that deals with a major marine faunal turnover during the Late Ordovician global greenhouse/icehouse episodes. It aims to document the diversity change of brachiopods (one of the major groups of marine life during the Ordovician Period) from pre-extinction to extinction times.

This timely book documents marvelous brachiopod fossils from the Palaeozoic-Mesozoic transition of South China. Numerous beautiful pictures and detailed descriptions (specifically the measurements of body size) of brachiopod species are presented. Systematic discussion on the evolution of brachiopod biodiversity and morphological features across the critical interval is not only extremely important for paleontologists to understand the marine ecosystem evolution from the Palaeozoic to the Mesozoic, but also attractive for students who need to know about the end-Permian mass extinction. The book distinguishes itself from other studies by its detailed study of the taxonomy, biodiversity and paleoecology of Permian-Triassic brachiopods from different palaeogeographic facies, especially from the deep-water environment in South China. The book also offers a unique study of the response of morphological features of brachiopods to palaeoenvironmental changes, providing insights for the process of Permian-Triassic crisis.