The rapid appearance of bilaterian clades at the beginning of the Phanerozoic is one of the most intriguing topics in macroevolution. However, the complex feedbacks between diversification and ecological interactions are still poorly understood. Here, we show that a systematic and comprehensive analysis of the trace-fossil record of the Ediacaran-Cambrian transition indicates that body-plan div...

The Cambrian Mt. Simon Sandstone (MSS) is a possible unconventional gas reservoir in the Illinois, Michigan, and Appalachian Basins, but comparatively little is known about the unit. This study used core and well logs from two deep exploratory wells to interpret the depositional environment of the MSS under western Ohio, where the MSS is about 120 m thick and found 1060 m below ground surface. ...

N o paleontological subject comes close to stimulating the public's interest like dinosaurs, but the origin of animals is probably a solid second. As is well known, representatives of nearly all of the animal phyla (e.g., arthropods, molluscs, echino-derms) appear at roughly the same moment in geologic time, the beginning of the Cambrian period, about 550 million years ago. Their sudden appeara...

Carbonate rocks of Neoproterozoic to Silurian age are abundantly distributed around the coasts North and North-East Greenland. Palaeokarst horizons particularly well developed within Portfjeld Formation (Ediacaran – earliest Cambrian) beneath Buen (Cambrian Series 2), there caves Ordovician limestones infilled by Caledonian molasse Middle Devonian age. The youngest karst is a series from Hall L...

Abstract The phylum Bryozoa had long been the only major unknown from Cambrian and by inference Explosion of biodiversity. When described in 2010 as a late cryptostome bryozoan, Pywackia baileyi Landing et al., became oldest known bryozoan (early bryozoans have since described). Controversy remains about phylum-level identification 2010—one study proposed an interpretation octocoral. No previou...