Time-averaging, the mixing of fossils of different ages within a single bed, defines the limit of temporal resolution of the fossil record. Quantitative estimates of this resolution threshold have not been acquired for any group other than mollusks. This study provides the first quantitative estimates of time-averaging for brachiopods, extending our understanding of intrinsic, or group specific...

The elastic buckling of shell structures such as spherical shells subject to external pressure and cylindrical shells loaded in axial compression is highly sensitive to imperfections and often catastrophic. Recent studies of spherical shells have provided accurate quantitative results for the relation between the buckling pressure and the amplitude and shape of geometric imperfections and, addi...

ISBN 978-3-540-92142-4 digitally watermarked, no DRM included format: PDF eBooks can be used on all Reading Devices.Pigmentation patterns of shells of mollusks a natural picture book to study dynamic. Scaphopods that one may find classified in a good seashell bookguide. Meinhardt, The Algorithmic Beauty of Sea Shells, Springer.This paper presents a method for modeling seashells, suitable for im...

The elastic properties of micrometer-sized hollow colloidal particles obtained by emulsion templating are probed by nanoindentation measurements in which point forces are applied to solvent-filled particles supported on a flat substrate. We show that the shells respond linearly up to forces of 7-21 nN, where the indentation becomes of the order of the shell thickness (20-40 nm). In the linear r...

—Bivalve death assemblages from subtidal environments within the tropical Bocas del Toro embayment of Caribbean Panama permit a test of the extent to which levels of damage are determined by the intrinsic nature of shell supply (proportion of epifaunal species, thick shells, calcitic shells, low-organic microstructures), as opposed to the extrinsic postmortem environment that shells experience....

Land hermit crabs hollow out the shells in which they live. A new study shows that remodelled shells afford better survival, with important implications for sociality and evolution.

concentrations of lead (pb) were found in the shells of the oyster saccostrea cucullata and sediments in may 2010. samples were obtained at four sites on qeshm island, at three sites on hormoz island, and at three sites in lengeh port along the intertidal coast of the persian gulf of iran. the levels of pb in sediments and shells were analyzed by graphite furnace atomic absorption spectrophotom...

BACKGROUND Tropical marine molluscs are traded globally. Larger species with slow life histories are under threat from over-exploitation. We report on the trade in protected marine mollusc shells in and from Java and Bali, Indonesia. Since 1987 twelve species of marine molluscs are protected under Indonesian law to shield them from overexploitation. Despite this protection they are traded openl...

Shell structures, especially cylindrical shells, are widely used in aerospace and naval architectural industries. Submarine hulls and aircraft bodies can be idealized as cylindrical shell structures. The study of vibrations of cylindrical shells is an important aspect in the successful applications of the cylindrical shells. The free vibration characteristics of a submarine hull have an importa...

The determination of the occurrence and level of cocoa shells in cocoa products and chocolate is an important analytical issue. The recent European Union directive on cocoa and chocolate products (2000/36/EC) has not retained the former limit of a maximum amount of 5% of cocoa shells in cocoa nibs (based on fat-free dry matter), previously authorized for the elaboration of cocoa products such a...