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.

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.

The principles of stratigraphic paleobiology can be readily applied to the nonmarine fossil record. Consistent spatial and temporal patterns of accommodation and sedimentation in sedimentary basins are an important control on stratigraphic architecture. Temperature and precipitation covary with elevation, causing significant variation in community composition, and changes in base level cause elevation to undergo predictable changes. These principles lead to eight sets of hypotheses about the nonmarine fossil record. Three relate to long-term and cyclical patterns in the preservation of major fossil groups and their taphonomy, as well as the occurrence of fossil concentrations. The remaining hypotheses relate to the widespread occurrence of elevation-correlated gradients in community composition, long-term and cyclical trends in these communities, and the stratigraphic position of abrupt changes in community composition. Testing of these hypotheses makes the stratigraphic paleobiology of nonmarine systems a promising area of investigation.

Trilobite! is an unashamedly trilobito-centric view of the world unravelling the history of the exotic, crustacean-like animals which dominated the seas for three hundred million years. These arthropods witnessed continents move, mountain chains elevated and eroded; they survived ice ages and volcanic eruptions, evolving and adapting exquisitely to their environment. They watched through their crystal eyes whilst life evolved. Their own evolution calibrated geological time itself.

Structured like a detective story, this is a light, but highly informative account of the wonders of scientific discovery.

Computational fluid dynamics (CFD), which involves using computers to simulate fluid flow, is emerging as a powerful approach for elucidating the palaeobiology of ancient organisms. Here, Imran A. Rahman describes its applications for studying fossil echinoderms. When properly configured, CFD simulations can be used to test functional hypotheses in extinct species, informing on aspects such as feeding and stability. They also show great promise for addressing ecological questions related to the interaction between organisms and their environment. CFD has the potential to become an important tool in echinoderm palaeobiology over the coming years.

The attraction of selenium isotopes as a paleoenvironmental tracer lies in the high redox potential of selenium oxyanions (SeIV and SeVI), the dominant species in the modern ocean. The largest isotopic fractionations occur during oxyanion reduction, which makes selenium isotopes a sensitive proxy for the redox evolution of our planet. As a case study we review existing data from the Neoarchean and Paleoproterozoic, which show that significant isotopic fractionations are absent until 2.5 Ga, and prolonged isotopic deviations only appear around 2.3 Ga. Selenium isotopes have thus begun to reveal complex spatiotemporal redox patterns not reflected in other proxies.

The diversity crisis in paleontology refers not to modern biota or the fossil record, but rather how our discipline lacks significant representation of individuals varying in race, ethnicity, and other aspects of identity. This Element is a call to action for broadening participation through improved classroom approaches as described in four sections. First, a brief review of the crisis and key concepts are presented. Next, culturally responsive pedagogy and related practices are introduced. Third, specific applications are offered for drawing cultural connections to studying the fossil record. Finally, recommendations including self-reflection are provided for fostering your own cultural competency. Our discipline offers much for understanding earth history and contributing new knowledge to a world impacted by humans. However, we must first more effectively welcome, support, and inspire all students to embrace meaning and value in paleontology; it is critical for securing the future of our field.

This book provides a wealth of geomathematical case history studies performed by the author during his career at the Ministry of Natural Resources Canada, Geological Survey of Canada (NRCan-GSC). Several of the techniques newly developed by the author and colleagues that are described in this book have become widely adopted, not only for further research by geomathematical colleagues, but by government organizations and industry worldwide. These include Weights-of-Evidence modelling, mineral resource estimation technology, trend surface analysis, automatic stratigraphic correlation and nonlinear geochemical exploration methods. The author has developed maximum likelihood methodology and spline-fitting techniques for the construction of the international numerical geologic timescale. He has introduced the application of new theory of fractals and multi fractals in the geostatistical evaluation of regional mineral resources and ore reserves and to study the spatial distribution of metals in rocks. The book also contains sections deemed important by the author but that have not been widely adopted because they require further research. These include the geometry of preferred orientations of contours and edge effects on maps, time series analysis of Quaternary retreating ice sheet related sedimentary data, estimation of first and last appearances of fossil taxa from frequency distributions of their observed first and last occurrences, tectonic reactivation along pre-existing schistosity planes in fold belts, use of the grouped jackknife method for bias reduction in geometrical extrapolations and new applications of the theory of permanent, volume-independent frequency distributions.

"Lucy is a 3.2-million-year-old skeleton who has become the spokeswoman for human evolution. She is perhaps the best known and most studied fossil hominid of the twentieth century, the benchmark by which other discoveries of human ancestors are judged.""-"From "Lucy's Legacy
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In his "New York Times" bestseller, "Lucy: The Beginnings of Humankind, " renowned paleoanthropologist Donald Johanson told the incredible story of his discovery of a partial female skeleton that revolutionized the study of human origins. Lucy literally changed our understanding of our world and who we come from. Since that dramatic find in 1974, there has been heated debate and-most important-more groundbreaking discoveries that have further transformed our understanding of when and how humans evolved.
In "Lucy's Legacy," Johanson takes readers on a fascinating tour of the last three decades of study-the most exciting period of paleoanthropologic investigation thus far. In that time, Johanson and his colleagues have uncovered a total of 363 specimens of Australopithecus afarensis (Lucy's species, a transitional creature between apes and humans), spanning 400,000 years. As a result, we now have a unique fossil record of one branch of our family tree-that family being humanity-a tree that is believed to date back a staggering 7 million years.
Focusing on dramatic new fossil finds and breakthrough advances in DNA research, Johanson provides the latest answers that post-Lucy paleoanthropologists are finding to questions such as: How did Homo sapiens evolve? When and where did our species originate? What separates hominids from the apes? What was the nature of Neandertal and modern human encounters? What mysteries about human evolution remain to be solved?
Donald Johanson is a passionate guide on an extraordinary journey from the ancient landscape of Hadar, Ethiopia-where Lucy was unearthed and where many other exciting fossil discoveries have since been made-to a seaside cave in South Africa that once sheltered early members of our own species, and many other significant sites. Thirty-five years after Lucy, Johanson continues to enthusiastically probe the origins of our species and what it means to be human.

"From the Hardcover edition."

Tracking initial ocean (de)oxygenation is critical to better constrain the coevolution of life and environment. Development of thallium isotopes has provided evidence to track the global manganese oxide burial which responds to early (de)oxygenation for short-term climate events. Modern oxic seawater thallium isotope values are recorded in organic-rich sediments deposited below an anoxic water column. An expansion of reducing conditions decrease manganese oxide burial and shifts the seawater thallium isotope composition more positive. Recent work documents that thallium isotopes are perturbed prior to carbon isotope excursions, suggesting ocean deoxygenation is a precursor for increased organic carbon burial. This Element provides an introduction to the application of thallium isotopes, case studies, and future directions.

The practice of paleontology has an aesthetic as well as an epistemic dimension. Paleontology has distinctively aesthetic aims, such as cultivating sense of place and developing a better aesthetic appreciation of fossils. Scientific cognitivists in environmental aesthetics argue that scientific knowledge deepens and enhances our appreciation of nature. Drawing on that tradition, this Element argues that knowledge of something's history makes a difference to how we engage with it aesthetically. This means that investigation of the deep past can contribute to aesthetic aims. Aesthetic engagement with fossils and landscapes is also crucial to explaining paleontology's epistemic successes.

The 'detective' power of stable isotopes for processes that occurred in the past, and for elucidating mechanisms at the molecular level, has impressed researchers over the past 100 years, since the time when isotopes of elements were first discovered. While most are interested in the normalized abundance ratios of two isotopes of an element, further power was unleashed when researchers investigated the relationship of three or more isotopes of the same element, e.g. 16O, 17O, and 18O for oxygen. This Element focuses on the history of discovery of triple isotope effects, the conceptual framework behind these effects, and major lines of development in the past few years of triple oxygen isotope research.

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.

New online resources are opening doors for education and outreach in the Earth sciences. One of the most innovative online earth science portals is Macrostrat and its mobile client Rockd - an interface that combines geolocated geological maps with stratigraphic information, lithological data, and crowd-sourced images and descriptions of outcrops. These tools provide a unique educational opportunity for students to interact with primary geological data, create connections between local outcrops and global patterns, and make new field observations. Rockd incorporates an aspect of social media to its platform, which creates a sense of community for users. This Element outlines these resources, gives instructions on how to use them, and provides examples of how to integrate these resources into a variety of paleontology and earth science courses.

Research on learning and cognition in geoscience education research and other discipline-based education communities suggests that effective instruction should include three key components: a) activation of students' prior knowledge on the subject, b) an active learning pedagogy that allows students to address any existing misconceptions and then build a new understanding of the concept, and c) metacognitive reflections that require students to evaluate their own learning processes during the lesson. This Element provides an overview of the research on student-centered pedagogy in introductory geoscience and paleontology courses and gives examples of these instructional approaches. Student-centered learning shifts the power and attention in a classroom from the instructor to the students. In a student-centered classroom, students are in control of their learning experience and the instructor functions primarily as a guide. Student-centered classrooms trade traditional lecture for conceptually-oriented tasks, collaborative learning activities, new technology, inquiry-based learning, and metacognitive reflection.

Hands-on learning in paleontology, and geology in general, is fairly common practice. Students regularly use rocks, fossils, and data in the classroom throughout their undergraduate career, but they typically do it sitting in a chair in a lab. Kinesthetic learning is a teaching model that requires students to be physically active while learning. Students may be involved in a physical activity during class or might be using their own bodies to model some important concept. This Element briefly discusses the theory behind kinesthetic learning and how it fits into a student-centered, active-learning classroom. It then describes in detail methods for incorporating it into student exercises on biostratigraphy, assessment of sampling completeness, and modeling evolutionary processes. Assessment data demonstrates that these exercises have led to significantly improved student learning outcomes tied to these concepts.

People hold a variety of prior conceptions that impact their learning. Prior conceptions that include erroneous or incomplete understandings represent a significant barrier to durable learning, as they are often difficult to change. While researchers have documented students' prior conceptions in many areas of geoscience, little is known about prior conceptions involving paleontology. In this Element, data on student prior conceptions from two introductory undergraduate paleontology courses are presented. In addition to more general misunderstandings about the nature of science, many students hold incorrect ideas about methods of historical geology, Earth history, ancient life, and evolution. Of special note are student perceptions of the limits of paleontology as scientific inquiry. By intentionally eliciting students' prior conceptions and implementing the pedagogical strategies described in other Elements in this series, lecturers can shape instruction to challenge this negative view of paleontology and improve student learning.

Lecturing has been a staple of university pedagogy, but a shift is ongoing because of evidence that active engagement with content helps strengthen learning and build more advanced skills. The flipped classroom, which delivers content to students outside of the class meeting, is one approach to maximize time for active learning. The fundamental benefit of a flipped class is that students learn more, but ensuring student preparation and engagement can be challenging. Evaluation policies can provide incentives to guide student effort. Flipping a class requires an initial time commitment, but the workload associated with evaluating student work during the course can be mitigated. The personal interactions from active learning are extremely rewarding for students and instructors, especially when class sizes are small and suitable room layouts are available. Overall, flipping a course doesn't require special training, just a willingness to experiment, reflect, and adjust.

Research-led, research-oriented, and research-based teaching incorporate research into teaching to different degrees. Research-led teaching focuses on content and informs students about current research findings, while research-oriented teaching focuses on techniques and often occurs in research methods courses. In research-based teaching, students participate in research. Through this involvement, they benefit from improved content knowledge, research skills, and life skills, as well as enhanced personal development. Research-embedded courses can make such benefits available to a wide range of students. Best practices in experiential learning and the incorporation of research in teaching include intentionality, planning, authenticity, reflection, training, monitoring, assessment, and acknowledgment. In this Element, these principles of best practice are illustrated by courses with embedded student research. Guidelines are presented for how to plan and execute a semester-long course-embedded research project, as well as alternative and shorter-term approaches. Research-based teaching provides challenges for students and faculty, but the benefits for all stakeholders are strong.

The educational benefits of replacing in-class lectures with hands-on activities are clear. Such active learning is a natural fit for paleontology, which can provide opportunities for examining fossils, analyzing data and writing. Additionally, there are a number of topics in the field that are exciting to geology majors and non-majors alike: very few can resist the lure of dinosaurs, huge meteor impacts, vicious Cretaceous sharks or a giant Pleistocene land mammal. However, it can seem difficult to introduce these techniques into a large general education class full of non-majors: paleontological specimens provide a natural starting point for hands-on classroom activities, but in a large class it is not always practical or possible to provide enough fossil material for all students. The Element introduces different types of active learning approaches, and then explains how they have been applied to a large introductory paleontology class for non-majors.

University dinosaur courses provide an influential venue for developing aptitude beyond knowledge of terrestrial Mesozoic reptiles. Passion for dinosaurs, when properly directed, can trigger interest in science and be used to develop critical thinking skills. Examination of dinosaur paleontology can develop competence in information analysis, perception of flawed arguments, recognition of persuasion techniques, and application of disciplined thought processes. Three methods for developing critical thought are outlined in this Element. The first uses dinosaur paleontology to illustrate logical fallacies and flawed arguments. The second is a method for evaluating primary dinosaur literature by students of any major. The final example entails critique of dinosaur documentaries based on the appearance of dinosaurs and the disconnect between scientific fact and storytelling techniques. Students are owed more than dinosaur facts; lecturers should foster a set of skills that equips students with the tools necessary to be perceptive citizens and science advocates.