Olduvai Groge is a valley in the Serengeti Plains at the western margin of the Eastern Rift Valley in northern Tanzania. The formations discussed in this volume, Beds I and II, were deposited in the Lower and Middle Pleistocene and have yielded large quantities of the remains of early man, in the form of bones and stone tools and evidence of the environment in which they lived. Bed I, in which remains of Australopithecus boisei and Homo habilis have been found, is firmly dated between 1.9 million years for the lowest level and 1.65 million years for a level below the top. This third volume describes the excavations. In Part I, starting with the lowest levels and devoting a chapter to each main level, Dr Leakey describes the actual process of excavation and the finding of the principal remains. In Part II, Dr Leakey describes the circumstances of the discovery of the hominid skeletal remains. These range from purposive excavation to accidental discovery while collecting small stones for mixing in concrete. Finally, mammalian bones, as tools and as food remains are discussed.

This book is a collection of papers presented in the symposia, held in Beijing, on palaeontology and historical geology. The papers deal with different topics, providing information on Palaeobiogeography and Palaeoecology of Asian countries, their faunal content, and fossil preservation.

The theory of evolution unites the past, present, and future of living things. It puts humanity's place in the universe into necessary perspective. Despite a history of controversy, the evidence for evolution continues to accumulate as a result of many separate strands of amazing scientific sleuthing. In The Story of Evolution in 25 Discoveries, Donald R. Prothero explores the most fascinating breakthroughs in piecing together the evidence for evolution. In twenty-five vignettes, he recounts the dramatic stories of the people who made crucial discoveries, placing each moment in the context of what it represented for the progress of science. He tackles topics like what it means to see evolution in action and what the many transitional fossils show us about evolution, following figures from Darwin to lesser-known researchers as they unlock the mysteries of the fossil record, the earth, and the universe. The book also features the stories of animal species strange and familiar, including humans-and our ties to some of our closest relatives and more distant cousins. Prothero's wide-ranging tales showcase awe-inspiring and bizarre aspects of nature and the powerful insights they give us into the way that life works. Brisk and entertaining while firmly grounded in fundamental science, The Story of Evolution in 25 Discoveries is a captivating read for anyone curious about the evidence for evolution and what it means for humanity.

IDEAL, the International Decade for East African Lakes, is a ten-year multi-national, multi-disciplinary investigation of the biological, geological, chemical, and physical limnology of the East African Lakes, taking into special account the Great Lakes of the East African Rift Valley and the climatology and paleoclimatology of the Rift Valley itself. The selected papers in this book serve as baseline knowledge for this intensive examination, with most of the contributing authors already actively researching these lakes. The oldest in the world and the largest on the continent, the lakes are vital resources for the indigenous populations of their basins. They are unique not only in their diverse populations of endemic species of fish and invertebrates, but in their sensitivity to climatic change, unusual circulation dynamics and water-column chemistry in relation to higher altitudes, and continuous record of climatic change in tropical Africa. This volume provides an overview of our current knowledge of the lakes combined with the most recent results of specific research efforts by African, American, and European investigators. Included also are some discussions on the impact of man, as well as comprehensive bibliographies.

Fossil crinoids are exceptionally suited to deep-time studies of community paleoecology and niche partitioning. By merging ecomorphological trait and phylogenetic data, this Element summarizes niche occupation and community paleoecology of crinoids from the Bromide fauna of Oklahoma (Sandbian, Upper Ordovician). Patterns of community structure and niche evolution are evaluated over a ~5 million-year period through comparison with the Brechin Lagerstatte (Katian, Upper Ordovician). The authors establish filtration fan density, food size selectivity, and body size as major axes defining niche differentiation, and niche occupation is strongly controlled by phylogeny. Ecological strategies were relatively static over the study interval at high taxonomic scales, but niche differentiation and specialization increased in most subclades. Changes in disparity and species richness indicate the transition between the early-middle Paleozoic Crinoid Evolutionary Faunas was already underway by the Katian due to ecological drivers and was not triggered by the Late Ordovician mass extinction.

This exciting new textbook examines the concepts of evolution as the underlying cause of the rich diversity of life on earth-and our danger of losing that rich diversity. Written as a college textbook, The Diversity and Evolution of Plants introduces the great variety of life during past ages, manifested by the fossil record, using a new natural classification system. It begins in the Proterozoic Era, when bacteria and bluegreen algae first appeared, and continues through the explosions of new marine forms in the Helikian and Hadrynian Periods, land plants in the Devonian, and flowering plants in the Cretaceous. Following an introduction, the three subkingdoms of plants are discussed. Each chapter covers one of the eleven divisions of plants and begins with an interesting vignette of a plant typical of that division. A section on each of the classes within the division follows. Each section describes where the groups of plants are found and their distinguishing features. Discussions in each section include phylogeny and classification, general morphology, and physiology, ecological significance, economic uses, and potential for research. Suggested readings and student exercises are found at the end of each chapter.

Studies of Sr isotopic composition of thousands of samples of marine sediments and fossils have yielded a curve of 87Sr/86Sr versus age for seawater Sr that extends back to 1 billion years. The ratio has fluctuated with large amplitude during this time period, and because the ratio is always uniform in the oceans globally at any one time, it is useful as a stratigraphic correlation and age-dating tool. The ratio also appears to reflect major tectonic and climatic events in Earth history and hence provides clues as to the causes, timing, and consequences of those events. The seawater 87Sr/86Sr ratio is generally high during periods marked by continent-continent collisions, and lower when continental topography is subdued, and seafloor generation rates are high. There is evidence that major shifts in the seawater ratio can be ascribed to specific orogenic events and correlate with large shifts in global climate.

It is a widely held belief that a climax vegetation of closed forest systems covered the lowlands of Central and Western Europe before humans intervened in prehistoric times to develop agriculture. If this intervention had not taken place, it would still be there and so if left, the grassland vegetation and fields we see today would revert to its natural closed forest state, although with a reduced number of wild species. This book challenges this view, using examples from history, pollen analyses and studies on the ecology of tree and shrub species such as oak and hazel. It tests the hypotheses that the climax vegetation is a closed canopy forest against the alternative one in which species composition and succession of vegetation were governed by herbivores and that the Central and Western European lowlands were covered by a park-like landscape consisting of grasslands, scrub, solitary trees and groves bordered by a mantle and fringe vegetation. Comparative information from North America is also included, because the forests there are commonly regarded as being analogous to the primeval vegetation in Europe. This title is a revised, updated and expanded translation of book published in Dutch.

The Paleobiological Revolution chronicles the incredible ascendance of the once-maligned science of paleontology to the vanguard of a field. With the establishment of the modern synthesis in the 1940s and the pioneering work of George Gaylord Simpson, Ernst Mayr, and Theodosius Dobzhansky, as well as the subsequent efforts of Stephen Jay Gould, David Raup, and James Valentine, paleontology became embedded in biology and emerged as paleobiology, a first-rate discipline central to evolutionary studies. Pairing contributions from some of the leading actors of the transformation with overviews from historians and philosophers of science, the essays here capture the excitement of the seismic changes in the discipline. In so doing, David Sepkoski and Michael Ruse harness the energy of the past to call for further study of the conceptual development of modern paleobiology.

Imaging and visualizing fossils in three dimensions with tomography is a powerful approach in paleontology. Here, the authors introduce select destructive and non-destructive tomographic techniques that are routinely applied to fossils and review how this work has improved our understanding of the anatomy, function, taphonomy, and phylogeny of fossil echinoderms. Building on this, this Element discusses how new imaging and computational methods have great promise for addressing long-standing paleobiological questions. Future efforts to improve the accessibility of the data underlying this work will be key for realizing the potential of this virtual world of paleontology.

The first English translation of Johannes Weigelt's 1927 classic makes available the seminal work in taphonomy, the study of how organisms die, decay, become entombed in sediments, and fossilize over time. Weigelt emphasized the importance of empirical work and made extensive observations of modern carcasses on the Texas Gulf Coast. He applied the results to evidence from the fossil record and demonstrated that an understanding of the postmortem fate of modern animals is crucial to making sound inferences about fossil vertebrate assemblages and their ecological communities. Weigelt spent sixteen months on the Gulf Coast in the mid-1920s, gathering evidence from the carcasses of cattle and other animals in the early stages of preservation. This book reports his observations. He discusses death and decomposition; classifies various modes of death (drowning, cold, dehydration, fire, mud, quicksand, oil slicks, etc.); documents and analyzes the positions of carcasses; presents detailed data on carcass assemblages at the Smither's Lake site in Texas; and, in a final chapter, makes comparisons to carcass assemblages from the geologic past. He raises questions about whether much of the fossil record is a product of unusual events and, if so, what the implications are for paleoecological studies. The English edition of Recent Vertebrate Carcasses includes a foreword and a translator's note that comment on Weigelt's life and the significance of his work. The original bibliography has been brought up to date, and, where necessary, updated scientific and place names have been added to the text in brackets. An index of names, places, and subjects is included, and Weigelt's own photographs of carcasses and drawings of skeletons illustrate the text.

The study of echinoid evolution, diversity, and ecology has always suffered from the fact that they are represented by taxa showing widely differing architectural designs of their multi-plated skeletons, inhabiting a large range of marine paleoenvironments, which result in highly varying taphonomic biases dictating their presence and recognition. This Element addresses the taphonomy of echinoids and includes: a general introduction to the morphological features of echinoids that play a role in their preservation; a review of processes which play an important role in the differential preservation of both regular and irregular echinoids including predation and transport; a summary of taphonomic pathways included in actualistic studies for recent sea urchins and then reconstructed for fossil taxa; and finally, a case study of the variation of echinoid taphonomy across a shelf gradient using the rich Miocene echinoid fauna of Sardinia.

Macroevolutionary inference has historically been treated as a two-step process, involving the inference of a tree, and then inference of a macroevolutionary model using that tree. Newer models blend the two steps. These methods make more complete use of fossils than the previous generation of Bayesian phylogenetic models. They also involve many more parameters than prior models, including parameters about which empiricists may have little intuition. In this Element, we set forth a framework for fitting complex, hierarchical models. The authors ultimately fit and use a joint tree and diversification model to estimate a dated phylogeny of the Cincta (Echinodermata), a morphologically distinct group of Cambrian echinoderms that lack the fivefold radial symmetry characteristic of extant members of the phylum. Although the phylogeny of cinctans remains poorly supported in places, this Element shows how models of character change and diversification contribute to understanding patterns of phylogenetic relatedness and testing macroevolutionary hypotheses.

Molybdenum (Mo) is a widely used trace metal for investigating redox conditions. However, unanswered questions remain that concentration and bulk isotopic analysis cannot specially answer. Improvements can be made by combining new geochemical techniques to traditional methods of Mo analysis. In this Element, we propose a refinement of Mo geochemistry within aquatic systems, ancient rocks, and modern sediments through molecular geochemistry (systematically combining concentration, isotope ratio, elemental mapping, and speciation analyses). Specifically, to intermediate sulfide concentrations governing Mo behavior below the 'switch-point' and dominant sequestration pathways in low oxygen conditions. The aim of this work is to 1) aid and improve the breadth of Mo paleoproxy interpretations by considering Mo speciation and 2) address outstanding research gaps concerning Mo systematics (cycling, partitioning, sequestration, etc.). The Mo paleoproxy has potential to solve ever complex research questions. By using molecular geochemical recommendations, improved Mo paleoproxy interpretations and reconstruction can be achieved.

The ideal textbook for non-science majors, this lively and engaging introduction encourages students to ask questions, assess data critically and think like a scientist. Building on the success of previous editions, Dinosaurs has been thoroughly updated to include new discoveries in the field, such as the toothed bird specimens found in China and recent discoveries of dinosaur soft anatomy. Illustrations by leading paleontological illustrator John Sibbick and new, carefully-chosen photographs, clearly show how dinosaurs looked, lived and their role in Earth history. Making science accessible and relevant through clear explanations and extensive illustrations, the text guides students through the dinosaur groups, emphasizing scientific concepts rather than presenting endless facts. Grounded in the common language of modern evolutionary biology - phylogenetic systematics - students learn to think about dinosaurs the way that professional paleontologists do.

Modern videography provides an ever-widening window into subsea echinoderm life with vast potential for new knowledge. Supported by video evidence throughout, this Element begins with time-lapse video made in 1983 on film, using an off-the-shelf camera, flash, and underwater housings. Although quality has now been significantly improved by digital imagery, films from over thirty years ago captured crinoid feeding behavior previously unknown and demonstrated a great potential to learn about many other aspects of their biology. This sequence is followed by several examples of recent digital videography from submersibles of deep-sea crinoids and remotely operated vehicles (ROVs) (stalked and unstalked), as well as close-up video of crinoids in aquaria. These recent studies enabled a new classification of crinoid arm postures, provided detailed views of food particle capture, and revealed a wide range of behaviors in taxa never before seen in life.

Knowledge of the evolutionary history of birds has much improved in recent decades. Fossils from critical time periods are being described at unprecedented rates and modern phylogenetic analyses have provided a framework for the interrelationships of the extant groups. This book gives an overview of the avian fossil record and its paleobiological significance, and it is the only up-to-date textbook that covers both Mesozoic and more modern-type Cenozoic birds in some detail. The reader is introduced to key features of basal avians and the morphological transformations that have occurred in the evolution towards modern birds. An account of the Cenozoic fossil record sheds light on the biogeographic history of the extant avian groups and discusses fossils in the context of current phylogenetic hypotheses. This review of the evolutionary history of birds not only addresses students and established researchers, but it may also be a useful source of information for anyone else with an interest in the evolution of birds and a moderate background in biology and geology.

Recent advances in statistical approaches called phylogenetic comparative methods (PCMs) have provided paleontologists with a powerful set of analytical tools for investigating evolutionary tempo and mode in fossil lineages. However, attempts to integrate PCMs with fossil data often present workers with practical challenges or unfamiliar literature. This Element presents guides to the theory behind and the application of PCMs with fossil taxa. Based on an empirical dataset of Paleozoic crinoids, example analyses are presented to illustrate common applications of PCMs to fossil data, including investigating patterns of correlated trait evolution and macroevolutionary models of morphological change. The authors emphasize the importance of accounting for sources of uncertainty and discuss how to evaluate model fit and adequacy. Finally, the authors discuss several promising methods for modeling heterogeneous evolutionary dynamics with fossil phylogenies. Integrating phylogeny-based approaches with the fossil record provides a rigorous, quantitative perspective on understanding key patterns in the history of life.

Nothing fills us with a sense of wonder like fossils. What looks at first like a simple rock is in fact a clue that reveals the staggering diversity of ancient environments, the winding pathways of evolution, and the majesty of a vanished earth. But as much as one might daydream of digging a hole in the backyard and finding a Tyrannosaurus, only a few places contain these buried treasures, and when a scientist comes across a remnant of prehistoric life, great care must be taken. What do budding paleontologists need to know before starting their search? In Fantastic Fossils, Donald R. Prothero offers an accessible, entertaining, and richly illustrated guide to the paleontologist's journey. He details the best places to look for fossils, the art of how to find them, and how to classify the major types. Prothero provides expert wisdom about typical fossils that an average person can hope to collect and how to hunt fossils responsibly and ethically. He also explores the lessons that both common and rarer discoveries offer about paleontology and its history, as well as what fossils can tell us about past climates and present climate change. Captivating illustrations by the paleoartist Mary Persis Williams bring to life hundreds of important specimens. Offering valuable lessons for armchair enthusiasts and paleontology students alike, Fantastic Fossils is an essential companion for all readers who have ever dreamed of going in search of traces of a lost world.

The stable chromium (Cr) isotope system has emerged over the past decade as a new tool to track changes in the amount of oxygen in earth's ocean-atmosphere system. Much of the initial foundation for using Cr isotopes ( 53Cr) as a paleoredox proxy has required recent revision. However, the basic idea behind using Cr isotopes as redox tracers is straightforward-the largest isotope fractionations are redox-dependent and occur during partial reduction of Cr(VI). As such, Cr isotopic signatures can provide novel insights into Cr redox cycling in both marine and terrestrial settings. Critically, the Cr isotope system-unlike many other trace metal proxies-can respond to short-term redox perturbations (e.g., on timescales characteristic of Pleistocene glacial-interglacial cycles). The Cr isotope system can also be used to probe the earth's long-term atmospheric oxygenation, pointing towards low but likely dynamic oxygen levels for the majority of Earth's history.

This volume reviews the meaning of taxonomic statements and considers our present knowledge regarding the number and characteristics of species among living and extinct primates, including man and his ancestors. They also examine the relationship of behaviour changes and selection pressures in evolutionary sequences. First published in 1964.

The history of life on earth is largely reconstructed from time-averaged accumulations of fossils. A glimpse at ecologic-time attributes and processes is relatively rare. However, the time-sensitive and predictability of echinoderm disarticulation makes them model organisms to determine post-mortem transportation and allows recognition of ecological-time data within paleocommunity accumulations. Unlike many other fossil groups, this has allowed research on many aspects of echinoderms and their paleocommunities, such as the distribution of soft tissues, assessment of the amount of fossil transportation prior to burial, determination of intraspecific variation, paleocommunity composition, estimation of relative abundance of taxa in paleocommunities, determination of attributes of niche differentiation, etc. Crinoids and echinoids have received the most amount of taphonomic research, and the patterns present in these two groups can be used to develop a more thorough understanding of all echinoderm clades.

The quantification of morphology through time is a vital tool in elucidating macroevolutionary patterns. Studies of disparity require intense effort but can provide insights beyond those gained using other methodologies. Over the last several decades, studies of disparity have proliferated, often using echinoderms as a model organism. Echinoderms have been used to study the methodology of disparity analyses and potential biases as well as documenting the morphological patterns observed in clades through time. Combining morphological studies with phylogenetic analyses or other disparate data sets allows for the testing of detailed and far-reaching evolutionary hypotheses.

Echinoderms elaborate a calcite skeleton composed of numerous plates with a distinct microstructure (stereom) that can be modelled into different shapes thanks to the use of a transient amorphous calcium carbonate (ACC) precursor phase and the incorporation of an intraorganic matrix during biomineralization. A variety of different types of stereom microarchitecture have been distinguished, each of them optimized for a specific function. For instance, a regular, galleried stereom typically houses collagenous ligaments, whereas an irregular, fine labyrinthic stereom commonly bears muscles. Epithelial tissues, in turn, are usually associated with coarse and dense stereom microfabrics. Stereom can be preserved in fossil echinoderms and a wide array of investigating methods are available. As many case studies have shown, a great deal of important paleobiological and paleoecological information can be decoded by studying the stereom microstructure of extinct echinoderms.