The colonization of the terrestrial environment by land plants transformed the planetary surface and its biota, and shifted the balance of Earth's biomass from the subsurface towards the surface. However there was a long delay between the formation of palaeosols (soils) on the land surface and the key stage of plant colonization. The record of palaeosols, and their colonization by fungi and lic...

Abstract The Sichuan Basin was a part of the Yangtze Carbonate Platform (YCP) during Cambrian–Ordovician, and marine carbonates were deposited in basin this interval. Although previous studies have evaluated paleogeography, paleoclimate paleoecology basin, they primarily focused on biological evolution basin; however, analysis paleogeography is lacking. This study integrated outcrop sedimentolo...

Selectivity patterns provide insights into the causes of ancient extinction events. The Late Ordovician mass extinction was related to Gondwanan glaciation; however, it is still unclear whether elevated extinction rates were attributable to record failure, habitat loss, or climatic cooling. We examined Middle Ordovician-Early Silurian North American fossil occurrences within a spatiotemporally ...

The Siluro-Ordovician Southern Uplands terrane occupies a key position in the Caledonian Orogen, yet its genesis is controversial. Marginal basin, back-arc and forearc tectonic regimes, operative at the Laurentian margin of the Iapetus Ocean, have all been invoked. Fresh andesitic detritus within turbidite sandstones has, until now, been assumed to provide evidence for an Ordovician, supra-subd...

Bivalves and gastropods are the two largest classes of extant molluscs. Despite sharing a huge number of features, they do not share a key ecological one: gastropods are essentially epibenthic, while most bivalves are infaunal. However, this is not the ancestral bivalve condition; Cambrian forms were surface crawlers and only during the Ordovician a fundamental infaunalization process took plac...

This is the first description of Ordovician cephalopods from Morocco. Although their occurrence has been known for a long time, only a poorly preserved conch from the late Katian of Ikhf n’Ouzerg (central Anti-Atlas) was described as “Orthoceras hastile Barrande” by Termier & Termier (1950). In some cases Ordovician cephalopods were mentioned within faunal lists without classification (e.g., Gu...

isotope data from bulk carbonates, micrite, marine calcite cements, non-skeletal grains and brachiopods indicate deposition of a wide spectrum of warm to cold water carbonates during the ordovician and the jurassic. this isotopic interpretation is supported by warm to cold climatic models proposed for the ordovician and the jurassic. these carbonates formed during the greenhouse mode (condition...

Ordovician conodont collections from several Argentinian basins including the Eastern Cordillera, Famatina and Precordillera allow recognition of a group conodonts that comprise new genus here named Condorodus n. gen. Species this have an apparatus composed six elements recovered so far: Pa, Pb, Sb1, Sb2, Sc Sd. The differences mainly between P support recognizing three species, older to younge...

Colonization of the land by plants most likely occurred in a stepwise fashion starting in the Mid-Ordovician. The earliest flora of bryophyte-like plants appears to have been cosmopolitan and dominated the planet, relatively unchanged, for some 30 million years. It is represented by fossilized dispersed cryptospores and fragmentary plant remains. In the Early Silurian, cryptospore abundance and...

Mass extinction events are recognized by increases in extinction rate and magnitude and, often, by changes in the selectivity of extinction. When considering the selective fingerprint of a particular event, not all taxon extinctions are equally informative: some would be expected even under a 'background' selectivity regime, whereas others would not and thus require special explanation. When ev...