Triangulating the Evolution of the Vertebral Column in the Last Common Ancestor
Triangulating the Evolution of the Vertebral Column in the Last Common Ancestor

Author: Burt Alain Rosenman

Publisher:

Published: 2008

Total Pages: 221

ISBN-13:

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The primate vertebral skeleton has been studied intensively by morphologists for more than a century and has become a focal point of investigation in biological anthropology. However, several issues regarding vertebral homology and anatomy remain controversial. I collected metric and non-metric data on 392 cercopithecine and hominoid spines to answer the following questions: First, what is the homology of the lumbar transverse process (LTP) in catarrhines? Second, how many lumbar vertebrae do early hominids possess? Third, how do last rib length, LTP width, and sacral width covary in catarrhines? Methods included data collection by caliper measurement as well as statistical tests such as ANCOVA. I conclude that all catarrhine primates share a similar LTP homology, in which the LTP is composed of a rib element ventrally and derivative of the thoracic transverse process dorsally. Based on these findings, I show that the early hominid specimens Sts 14 and Stw 431 possessed a minimum of six functional lumbar vertebrae. In the metric comparisons, I find that humans have relatively short last ribs; that, in addition to their relatively narrow sacra, the African apes have narrow penultimate and ultimate lumbar vertebrae; and that the early hominids Sts 14 and AL 288-1 have the relatively widest LTPs and sacra of the taxa studied. Incorporating all these data, I present a model of hominoid lumbar vertebral evolution in which each of the great apes has independently evolved a short lumbar spine of three to four segments. Therefore, the long lumbar column of early hominids was most likely a primitive retention, and it is not derived as is commonly assumed.

Hominin Postcranial Remains from Sterkfontein, South Africa, 1936-1995
Hominin Postcranial Remains from Sterkfontein, South Africa, 1936-1995

Author: Bernhard Zipfel

Publisher: Oxford University Press, USA

Published: 2020

Total Pages: 401

ISBN-13: 0197507662

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The Sterkfontein hominin fossils generally are attributed to the species Australopithecus africanus, because most craniodental remains from the site are attributable to that taxon (reviews in Grine, 2013, 2019). However, there may be more than one hominin represented within the sample, even within the most productive Member, Member 4, and given the complex stratigraphy of the site and challenges in dating the deposits, this may or not may be the case. In general. Several studies have suggested the presence of two or more australopith taxon within the sample, each citing more morphological variation among the craniodental remains from Sterkfontein that can be attributed to a single species, at least compared to extant hominoid taxa (Kimbel and White, 1988; Clarke 1988, 1994; Lockwood, 1997, Lockwood and Tobias, 2002). However, it is notable that none of these studies agree on which specimens comprise the different possible taxa or groups, largely due to emphasis on different aspects of morphology varying among the fossils. The likely time depth of the Sterkfontein sample, even within Member 4, (see Chapter 3, this volume), may also complicate assessment of potential taxonomic heterogeneity at the site. None of the Sterkfontein postcranial fossils can be definitively associated with any craniodental specimens (but see Thackeray et al., 2002), and so cannot be related directly to any of the proposed taxonomic divisions within the sample. However, some studies have cited variation within the postcranial fossils that may also reflect taxonomic variation, although many studies to date have not tackled this question rigorously. Even though these suggestions have been made occasionally in the literature, no clear or consistent suggestion of two or more taxa has been apparent within the postcranial samples (reviewed in Grine 2019). Taxonomic variation is one of the key questions that each chapter in this volume addresses (summarized in Chapter 18, this volume)"--

Spinal Evolution
Spinal Evolution

Author: Ella Been

Publisher: Springer

Published: 2019-08-07

Total Pages: 407

ISBN-13: 3030193497

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The vertebral spine is a key element of the human anatomy. Its main role is to protect the spinal cord and the main blood vessels. The axial skeleton, with its muscles and joints, provides stability for the attachment of the head, tail and limbs and, at the same time, enables the mobility required for breathing and for locomotion. Despite its great importance, the vertebral spine is often over looked by researchers because: a) vertebrae are fragile in nature, which makes their fossilization a rare event; b) they are metameric (seriated and repeated elements) that make their anatomical determination and, thus, their subsequent study difficult; and c) the plethora of bones and joints involved in every movement or function of the axial skeleton makes the reconstruction of posture, breathing mechanics and locomotion extremely difficult. It is well established that the spine has changed dramatically during human evolution. Spinal curvatures, spinal load transmission, and thoracic shape of bipedal humans are derived among hominoids. Yet, there are many debates as to how and when these changes occurred and to their phylogenetic, functional, and pathological implications. In recent years, renewed interest arose in the axial skeleton. New and exciting finds, mostly from Europe and Africa, as well as new methods for reconstructing the spine, have been introduced to the research community. New methodologies such as Finite Element Analysis, trabecular bone analysis, Geometric Morphometric analysis, and gait analysis have been applied to the spines of primates and humans. These provide a new and refreshing look into the evolution of the spine. Advanced biomechanical research regarding posture, range of motion, stability, and attenuation of the human spine has interesting evolutionary implications. Until now, no book that summarizes the updated research and knowledge regarding spinal evolution in hominoids has been available. The present book explores both these new methodologies and new data, including recent fossil, morphological, biomechanical, and theoretical advances regarding vertebral column evolution. In order to cover all of that data, we divide the book into four parts: 1) the spine of hominoids; 2) the vertebral spine of extinct hominins; 3) ontogeny, biomechanics and pathology of the human spine; and 4) new methodologies of spinal research. These parts complement each other and provide a wide and comprehensive examination of spinal evolution.

The Notochord
The Notochord

Author: P. Eckhard Witten

Publisher: CRC Press

Published: 2022-05-09

Total Pages: 301

ISBN-13: 1351652036

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Although it is the defining organ of the Chordata, the notochord and its cells are one of the least understood vertebrate organs. This may be because large parts of the notochord are often replaced with cartilaginous or bony vertebral bodies. The presence of cartilage in the notochord raises questions about the evolutionary relationships between notochord cells and cartilage cells. This book integrates classical analytical studies with recent palaeontological, experimental, and molecular studies in both developmental and evolutionary contexts. For example, although the early signaling function of the notochord is conserved across the vertebrates, many will be surprised to find that the role of the notochord in vertebral body development in tetrapods is not the blueprint for all vertebrates. Recent studies on zebrafish and medaka embryos have uncovered the molecular mechanisms of a somite-independent notochord-driven segmentation process that establishes vertebral centra and intervertebral spaces. As this process is not restricted to teleosts, the authors have written a general discussion about the role of the notochord in vertebral formation. Modularity and segmentation of the vertebral column are related topics. Further overarching themes are the structure, function and fate of the notochord in adult vertebrates and notochord–cartilage relationships. Key Features The first book devoted to notochord development, function and evolution Includes and integrates information on the notochord from studies going back 169 years Integrates developmental, molecular, functional, experimental and palaeontological studies Documents the fate of the notochord across the vertebrates Extensively illustrated with classical and new images Related Titles Bard, J. Evolution: The Origins and Mechanisms of Diversity (ISNB 978-0-3673-5701-6) Leys, S. and Hejnol. A. Origin and Evolution of Metazoan Cell Types (ISBN 978-1-1380-3269-9)

The Ancient Origins of Consciousness
The Ancient Origins of Consciousness

Author: Todd E. Feinberg

Publisher: MIT Press

Published: 2016-03-25

Total Pages: 387

ISBN-13: 0262333279

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How consciousness appeared much earlier in evolutionary history than is commonly assumed, and why all vertebrates and perhaps even some invertebrates are conscious. How is consciousness created? When did it first appear on Earth, and how did it evolve? What constitutes consciousness, and which animals can be said to be sentient? In this book, Todd Feinberg and Jon Mallatt draw on recent scientific findings to answer these questions—and to tackle the most fundamental question about the nature of consciousness: how does the material brain create subjective experience? After assembling a list of the biological and neurobiological features that seem responsible for consciousness, and considering the fossil record of evolution, Feinberg and Mallatt argue that consciousness appeared much earlier in evolutionary history than is commonly assumed. About 520 to 560 million years ago, they explain, the great “Cambrian explosion” of animal diversity produced the first complex brains, which were accompanied by the first appearance of consciousness; simple reflexive behaviors evolved into a unified inner world of subjective experiences. From this they deduce that all vertebrates are and have always been conscious—not just humans and other mammals, but also every fish, reptile, amphibian, and bird. Considering invertebrates, they find that arthropods (including insects and probably crustaceans) and cephalopods (including the octopus) meet many of the criteria for consciousness. The obvious and conventional wisdom–shattering implication is that consciousness evolved simultaneously but independently in the first vertebrates and possibly arthropods more than half a billion years ago. Combining evolutionary, neurobiological, and philosophical approaches allows Feinberg and Mallatt to offer an original solution to the “hard problem” of consciousness.

Feeding in Vertebrates
Feeding in Vertebrates

Author: Vincent Bels

Publisher: Springer

Published: 2019-04-23

Total Pages: 865

ISBN-13: 3030137392

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This book provides students and researchers with reviews of biological questions related to the evolution of feeding by vertebrates in aquatic and terrestrial environments. Based on recent technical developments and novel conceptual approaches, the book covers functional questions on trophic behavior in nearly all vertebrate groups including jawless fishes. The book describes mechanisms and theories for understanding the relationships between feeding structure and feeding behavior. Finally, the book demonstrates the importance of adopting an integrative approach to the trophic system in order to understand evolutionary mechanisms across the biodiversity of vertebrates.

Reading Prehistoric Human Tracks
Reading Prehistoric Human Tracks

Author: Andreas Pastoors

Publisher: Springer Nature

Published: 2021

Total Pages: 437

ISBN-13: 3030604063

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This Open Access book explains that after long periods of prehistoric research in which the importance of the archaeological as well as the natural context of rock art has been constantly underestimated, research has now begun to take this context into focus for documentation, analysis, interpretation and understanding. Human footprints are prominent among the long-time under-researched features of the context in caves with rock art. In order to compensate for this neglect an innovative research program has been established several years ago that focuses on the merging of indigenous knowledge and western archaeological science for the benefit of both sides. The book gathers first the methodological diversity in the analysis of human tracks. Here major representatives of anthropological, statistical and traditional approaches feature the multi-layered methods available for the analysis of human tracks. Second it compiles case studies from around the globe of prehistoric human tracks. For the first time, the most important sites which have been found worldwide are published in a single publication. The third focus of this book is on firsthand experiences of researchers with indigenous tracking experts from around the globe, expounding on how archaeological sciencecan benefit from the ancestral knowledge. This book will be of interest to professional archaeologists, graduate students, ecologists, cultural anthropologists and laypeople, especially those focussing on hunting-gathering and pastoralist communities and who appreciate indigenous knowledge.--

Encyclopedia of Biology
Encyclopedia of Biology

Author: Don Rittner

Publisher: Infobase Publishing

Published: 2004-08

Total Pages: 417

ISBN-13: 1438109997

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Contains approximately 800 alphabetical entries, prose essays on important topics, line illustrations, and black-and-white photographs.

Clinical Anatomy of the Lumbar Spine and Sacrum
Clinical Anatomy of the Lumbar Spine and Sacrum

Author: Nikolai Bogduk

Publisher: Elsevier Health Sciences

Published: 2005-01-01

Total Pages: 262

ISBN-13: 0443101191

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Bogduk aims to provide a foundation of knowledge upon which an understanding of the various treatment and therapy techniques of the different specialities involved can be built. This edition includes discussion of the sacrum and sacro-iliac joint.