Molluscan shells are externally fabricated by specialized epithelial cells on the dorsal
mantle. Although a conserved set of regulatory genes appears to underlie specification of …

Abrupt appearance of major bilaterian clades in the fossil record during the first three stages
of the Cambrian Period has puzzled the scientific world since 1830s. Many proposed causes …

The end of the Permian period is marked by global warming and the biggest known mass
extinction on Earth. The crisis is commonly attributed to the formation of the Siberian Traps …

The transition between the Proterozoic and Phanerozoic eons, beginning 542 million years
(Myr) ago, is distinguished by the diversification of multicellular animals and by their …

Abstract The “Cambrian Explosion” is known for rapid increases in the morphological
disparity and taxonomic diversity of metazoans. It has been widely proposed that this …

This chapter focuses almost exclusively on marine evaporites and in particular on how the
chemistry of seawater is reflected in the mineralogy and facies distribution of deposits in …

Oil and gas discoveries within Proterozoic-Cambrian strata and the majority of shale gas
production occurs in relatively stable tectonic regions and characterised by moderate …

Microbially mediated calcification can be traced back for at least 2.6 billion years. Although
morphological comparison of fossil and recent microbial carbonates suggests that …

Iron is a remarkable element in its relatively high abundance for its mass and its sensitivity to
(and control of) redox on a planetary scale over geologic time. Numerous volumes have …

Nitrogen and sulfur are abundant constituents of plant and algal cells that are assimilated at
the lowest oxidation number, as NH 4+ and S 2−, although they can (in the case of sulfur …