Graptolites flourished from earliest Ordovician to Early Devonian, a time range of about 90 million years, and were widely distributed as marine benthic and planktonic colonial organisms around then-world.

The graptolites constitute one of the geologically most useful taxonomic groups of fossils for dating rock successions, understanding paleobiogeography and reconstructing plate tectonic configurations in the Lower Palaeozoic. Graptolites were largely planktic, marine organisms, and as one of the first groups that explored the expanses of the world’s oceans are vital for understanding Palaeozoic ecology. They are the best and often the only fossil group for dating Lower Palaeozoic rock successions precisely. Thousands of taxa have been described from all over the planet and are used for a wide variety of geological and palaeontological (biological) research topics. The recent recognition of the modern pterobranch Rhabdopleura as a living benthic graptolite enables a much better understanding and interpretation of the fossil Graptolithina. In the decades since the latest edition of the Graptolite Treatise, the enormous increase of knowledge on this group of organisms has never been synthesised in a compelling and coherent way, and information is scattered in scientific publications and difficult to sort through. This volume provides an up-to-date insight into research on graptolites. Such research has advanced considerably with the use of new methods of investigation and documentation. SEM investigation and research on ultrastructure of the tubaria has made it possible to compare extant and extinct taxa in much more detail. Cladistic interpretation of graptolite taxonomy and evolution has advanced the understanding of this group of organisms considerably in the last two decades, and has highlighted their importance in our understanding of evolutionary processes. This book will show graptolites, including their modern, living relatives, in a quite new and fascinating light, and will demonstrate the impact that the group has had on the evolution of the modern marine ecosystem. This book is aimed not only at earth scientists but also at biologists, ecologists and oceanographers. It is a readable and comprehensible volume for students at the MSc level, while remaining accessible to undergraduates and non-specialists seeking up-to-date information about this fascinating topic in palaeobiology.

The Early Palaeozoic was a critical interval in the evolution of marine life on our planet. Through a window of some 120 million years, the Cambrian Explosion, Great Ordovician Biodiversification Event, End Ordovician Extinction and the subsequent Silurian Recovery established a steep trajectory of increasing marine biodiversity that started in the Late Proterozoic and continued into the Devonian. Biogeography is a key property of virtually all organisms; their distributional ranges, mapped out on a mosaic of changing palaeogeography, have played important roles in modulating the diversity and evolution of marine life. This Memoir first introduces the content, some of the concepts involved in describing and interpreting palaeobiogeography, and the changing Early Palaeozoic geography is illustrated through a series of time slices. The subsequent 26 chapters, compiled by some 130 authors from over 20 countries, describe and analyse distributional and in many cases diversity data for all the major biotic groups plotted on current palaeogeographic maps. Nearly a quarter of a century after the publication of the ‘Green Book’ (Geological Society, London, Memoir12, edited by McKerrow and Scotese), improved stratigraphic and taxonomic data together with more accurate, digitized palaeogeographic maps, have confirmed the central role of palaeobiogeography in understanding the evolution of Early Palaeozoic ecosystems and their biotas.

This volume focuses on the broad pattern of increasing biodiversity through time, and recurrent events of minor and major ecosphere reorganization. Intense scrutiny is devoted to the pattern of physical (including isotopic), sedimentary and biotic circumstances through the time intervals during which life crises occurred. These events affected terrestrial, lacustrine and estuarine ecosystems, locally and globally, but have affected continental shelf ecosystems and even deep ocean ecosystems. The pattern of these events is the backdrop against which modelling the pattern of future environmental change needs to be evaluated.