Two distinct regimes of extinction dynamic are present in the major marine zooplankton
group, the graptolites, during the Ordovician and Silurian periods (486− 418 Ma). In …

The upper Silurian, and especially Pridoli epoch is a critical interval for the understanding
the evolution of Earth's biota, since it witnessed series of powerful extinction events, global …

This paper presents a proposal for a taxonomic approach to the classification of the
Pterobranchia (Cephalodiscida and Graptolithina) to be adopted for the revision of the …

The Silurian was a time of major climatic transition punctuated by multiple biotic crises and
global carbon cycle perturbations. The most severe of these biotic events was the late …

The mid-Ludfordian carbon isotope excursion (CIE) is probably the most intensively studied
of all Palaeozoic geochemical events. This is mainly due to the fact that it represents the …

Abstract The Homerian to Ludfordian interval of the mid to late Silurian Period was a time of
significant changes in conodont communities, global climate, oceanographic patterns and …

The Hemichordata are generally interpreted as early deuterostomes, closely related to the
chordates, a notion important for modern analyses of the origin of the deuterostomes …

Graptolites were planktonic organisms that constitute one of the essential biostratigraphic
tools used in Paleozoic successions worldwide. Notably, Pridolian (upper Silurian) …

Two new eurypterids, a pterygotid Pterygotus wanggaii n. sp. and an adelophthalmoid
Parahughmilleria fuea n. sp., are described from the Early Devonian (Lochkovian) …

In the cladistic literature, there is a recurrent perspective that considers homoplasy as
something undesirable. Homoplasy, according to this view, is believed to obscure …