Fossil echinoderms, including the common Cambrian and Ordovician echinoderms figured here (Fig. 1 from Deline, et al., 2021; request permission to use here) have a rich and diverse fossil record.

Life at the start of the Ordovician remained confined to the seas with new animals evolving in place of those that didn't survive the Cambrian. Chief among them were the squidlike nautiloids ...

Arthropods were the most diverse animal group in the Cambrian period and the Ordovician period that followed. The 452-million-year-old limestone slab shown here captures an Ordovician menagerie ...

Inspired by the early life forms of prehistoric worms and other invertebrates that triggered the Great Ordovician ...

We study trilobites from four periods of the Palaeozoic: the Cambrian, Ordovician, Silurian and Devonian. Our research covers trilobite taxonomy, phylogeny, functional morphology, biogeography, and ...

Late Ordovician Period - The Ordovician Period refers to the ... Trilobites are found among the oldest well-preserved fossils in the Lower Cambrian period. Cincinnati area rocks are filled with ...

Though unfinished, Salter's monograph has thirty excellent plates which make it an essential starting point for the study of British Devonian, Silurian and Ordovician trilobites. The monograph is also ...

Simple, single-celled algae would have made enough oxygen via photosynthesis to sustain trilobites, clamlike brachiopods, worms, and other life-forms that came into existence during the Cambrian ...

Using full-colour palaeogeographical maps from the Cambrian to the present, this interdisciplinary volume explains how plate motions and surface volcanism are linked to processes in the Earth's mantle ...

The park’s namesake rocks formed eons ago, starting during the Late Precambrian, Cambrian, and Early Ordovician Periods ...

The Snowdonia scenery has been hundreds of millions of years in the making and is dominated by sedimentary and volcanic rocks from the Cambrian and Ordovician periods. Admire sites such as South ...

Dr. William Harrison is professor emeritus in the Department of Geological and Environmental Sciences at Western Michigan University. In his 30 year teaching career, he supervised and served on ...