Download or read book The Developmental Basis of Variation in Tooth and Jaw Patterning written by Theresa M Grieco and published by . This book was released on 2013 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perhaps the most evident conversion of genomic information into functional, morphological phenotypes in an animal occurs during organogenesis, and the study of vertebrate tooth development provides a phenotypically diverse system for which the mechanisms for patterning and morphogenesis have been extensively studied. An understanding of the developmental basis for evolved differences between teeth in different anatomical and phylogenetic contexts brings complementary information to our knowledge of odontogenic mechanisms. Examining difference, or variation, allows for the validation of hypothesized developmental mechanisms, identification of mechanistic flexibility that could be available to evolution or bioengineering, and the redefinition of phenotypes to better align with the natural biological variation available. This dissertation examines the development of the dentition in the frog and emerging developmental model Silurana (Xenopus) tropicalis, including the first gene expression data for odontogenesis in any amphibian. Comparative data for the evolution of dental phenotypes are assembled from descriptions of tooth initiation, dentition patterning, and adult craniodental variation phenotypes, addressing developmental questions at population, subfamily, and phylum levels. Using hematoxylin and eosin-stained histological sections and whole mount preparations of larval S. tropicalis jaws, I demonstrate that individual tooth initiation is broadly similar to that documented for phylogenetic relative Xenopus laevis, but that the process is temporally shifted relative to external developmental traits in the Nieuwkoop and Faber staging system. Furthermore, patterns of tooth initiation in S. tropicalis reveal a lack of synchrony in alternating tooth positions and dynamics that were previously undetected. The frequent presence of 'twinned' tooth germs in whole mount preparations argues against a robust model of local inhibition directing tooth initiation in this species. These findings rule out two hypothesized developmental mechanisms for tooth initiation in S. tropicalis that were derived from data in X. laevis and other homodont vertebrates. In another investigation of first generation tooth development, I examine the expression of Sonic hedgehog (Shh) , a marker for several phases of odontogenesis across vertebrates. I demonstrate the utility of comparing 'natural experiments' in development with what is known from more anatomically conservative developmental models. In particular, I use the fact that S. tropicalis teeth do not initiate until just before metamorphosis as a case where tooth formation and mouth formation developmental programs are dissociated from one another to evaluate the current consensus odontogenic model for Shh. With in situ hybridization data from S. tropicalis, I fail to detect a Shh-expressing odontogenic band prior to tooth formation, counter to predictions from the consensus model. A review of published functional data and the correspondence between an odontogenic band domain and the presence of functional teeth in other vertebrates reveal several other taxa for which the consensus model appears insufficient to account for variation in the distribution of the marginal dentition. Finally, I explore the ability to infer developmental processes from patterns of adult craniodental variation in three S. tropicalis genetic strains raised in captivity. Osteological measurements and tooth counts are analyzed for patterns of covariation at the functional phenotypic levels of the cranium, the jaw, and the tooth-bearing bone. I demonstrate that the bimodal sexual body length dimorphism does not carry over to any cranial metric trait measured; systemic factors affecting cranial length can explain much of the difference between male and female traits, which are distributed unimodally. Patterns of covariation with cranial size, size-adjusted patterns of pairwise phenotypic correlation, and significant differences between genetic strains all suggest a relative independence of variation in the premaxilla and maxilla in S. tropicalis, and I document evidence for a functional jaw module, in which the tooth row and jaw bones correlate when summed across the jaw, but in which tooth and jaw phenotypes lack integration at the level of individual tooth-bearing bones.

Download or read book Developmental Genetic Basis of Stickleback Evolved Tooth Gain written by Nicholas Ellis and published by . This book was released on 2016 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: An abundance of morphological diversity is seen across nature yet we know little of the mechanistic underpinnings of these evolved changes. Developmental patterning is achieved by relatively few signaling pathways, which have been modified throughout evolution to give rise to the various forms we see today. Despite extensive studies characterizing mutant phenotypes under laboratory settings, we still know little about the developmental and genetic mechanisms underlying evolved phenotypes in nature. Outstanding questions include: How have developmental mechanisms been modified? When the same phenotype evolves, are the genetic bases the same or different? And in cases with continuously regenerating morphology, how are these phenotypes maintained over time and what signaling pathways play a role? In this dissertation I address these questions using the teeth of the threespine stickleback fish, Gasterosteus aculeatus, as a model. Teeth have long served as a model system to study basic questions about vertebrate organogenesis, morphogenesis, and evolution. In most non-mammalian vertebrates, teeth regenerate throughout adult life. New model systems that undergo continuous tooth replacement are sorely needed to complement developmental studies of tooth formation in mice, which do not replace their teeth. Fish have evolved a tremendous amount of diversity in dental patterning in both their oral and pharyngeal dentitions, offering numerous opportunities to study how morphology develops, regenerates, and evolves in different lineages. Threespine stickleback fish have emerged as a new system to study how morphology evolves, and provide a particularly powerful system to study the development and evolution of dental morphology. Sticklebacks have undergone an adaptive radiation, with oceanic marine populations repeatedly colonizing and rapidly adapting to freshwater lakes and creeks throughout the northern hemisphere. Colonization of freshwater environments is accompanied by a variety of changes to the head skeleton, many of which are likely adaptive for the major shift in diet from small zooplankton in the ocean to larger prey in freshwater. Natural variation in dental patterning exists between stickleback fish populations providing an opportunity to dissect the developmental genetic basis of tooth formation and replacement. Marine and freshwater sticklebacks can be intercrossed and their F1 hybrids are fertile, allowing forward genetic mapping of genomic regions controlling evolved differences. In chapter 1, I introduce the oral and pharyngeal dentition in sticklebacks and provide morphological, histological, and molecular evidence for homology of oral and pharyngeal teeth. Next, using a dense developmental time-course of lab-reared animals, the temporal and spatial sequence of early tooth formation for the ventral pharyngeal dentition is described. This sequence is highly stereotypical allowing the characterization of the first tooth replacement event and providing a guide for future phenotyping. Finally, the early sequence of tooth development is compared to that described in other fish, revealing that major changes to how dental morphology arises and regenerates have evolved across different fish lineages. In chapter 2, I focus on how the variation in dental patterning manifests during development. Previous work had identified a freshwater population with increased tooth number arising late in development, however the mechanism of how teeth were gained over time remained elusive. Here, using a vital dye pulse-chase method, we showed increased tooth number results from an increased tooth replacement rate. We also identified a second freshwater population which has convergently evolved tooth gain allowing us to study whether the developmental and genetic bases underlying this phenotype are the same or different. Despite the similar evolved phenotype of more teeth and an accelerated adult replacement rate, the timing of tooth number divergence and the spatial patterns of newly formed teeth are different in the two freshwater populations, suggesting distinct developmental mechanisms underlie the evolved changes. Using genome-wide linkage mapping in marine-freshwater F2 genetic crosses, we found largely non-overlapping genomic regions controlling tooth patterning in the two high-toothed populations. This work represents one of the first demonstrations of distinct developmental genetic bases underlying evolved changes in morphology in vertebrates. In chapter 3, I test the role of BMP signaling on stickleback tooth formation and replacement. Although distinct genomic regions underlying evolved tooth gain in two freshwater populations were identified, the reoccurrence of BMP pathway members (ex. Bmp6, Msxe, Bmp7a) appearing as candidates in loci underlying evolved tooth gain suggests the hypothesis that changes in different components of the BMP signaling pathway underlies convergent evolution of tooth gain. Using the small molecule BMP signaling inhibitor LDN-193189, we showed BMP signaling plays both positive and negative roles in tooth development and replacement. BMP knockdown results in failure to initiate late forming primary positions while premature replacement occurs at early, established tooth positions. Notably, this accelerated tooth replacement is independent of tooth shedding and may be a mechanism used to evolved gains in tooth number. Late in development at a stage after individual tooth positions can be tracked, BMP knockdown in marine fish increased the number of newly forming teeth, likely due to increased tooth replacement. Collectively these data suggest that during stickleback tooth formation and replacement, BMPs positively regulate tooth development while negatively regulating tooth replacement and suggest this pathway has been modified during freshwater adaptation to achieve evolved tooth gain. In chapter 4, I provide a protocol demonstrating how to dissect and flat-mount the internal branchial skeleton. By mounting this complex three-dimensional skeleton into largely two-dimensions, one can easily phenotype a variety of internal traits including pharyngeal tooth patterning. This method is a fast and relatively inexpensive way to study variation of trophic traits and is also applicable to a wide variety of fish species. In sticklebacks, we have used this method to visualize and precisely measure skeletal morphology in genetic crosses to map genomic regions controlling craniofacial patterning. Together this dissertation makes significant progress toward understanding the developmental genetic basis of evolved tooth gain in stickleback fish. These results have broad implications for understanding the repeatability of evolution, mechanisms of evolved gain traits, the process and signaling pathways of tooth replacement, and how signaling pathways can be modulated to produce morphological variation.

Download or read book The Teeth of Non mammalian Vertebrates written by Barry Berkovitz and published by Elsevier. This book was released on 2023-06-17 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Teeth of Non-Mammalian Vertebrates: Form, Function, Development and Growth, Second Edition is devoted to the teeth and dentitions of living fishes, amphibians, and reptiles. This book presents a comprehensive survey of the wide variety of tooth forms among non-mammalian vertebrates, based on descriptions of approximately 450 species belonging to about 170 families.This latest edition discusses the functional morphology of feeding, the attachment of teeth, and the relationship of tooth form to function, with each chapter accompanied by a comprehensive, up-to-date reference list. Following the descriptions of the teeth and dentitions in each class, four chapters review current topics with considerable research activity: tooth development; tooth replacement; and the structure, formation, and evolution of the dental hard tissues. The Teeth of Non-Mammalian Vertebrates: Form, Function, Development and Growth, Second Edition is authored by internationally recognized teachers and researchers in the field. This new edition reflects the resurgence of interest in the dentitions of non-mammalian vertebrates as experimental systems to help understand genetic changes in evolution of teeth and jaws. Features more than 650 images, including photographs from internationally recognized researchers and world class collections Offers in depth information on tooth structure, development, attachment, and replacement Provides detailed descriptions of the dentitions of all living groups of non-mammalian vertebrates Discusses the relationship between tooth form and structure to function in the feeding process

Download or read book Jaws written by Sandra Kahn and published by Stanford University Press. This book was released on 2018-04-10 with total page 267 pages. Available in PDF, EPUB and Kindle. Book excerpt: There's a silent epidemic in western civilization, and it is right under our noses. Our jaws are getting smaller and our teeth crooked and crowded, creating not only aesthetic challenges but also difficulties with breathing. Modern orthodontics has persuaded us that braces and oral devices can correct these problems. While teeth can certainly be straightened, what about the underlying causes of this rapid shift in oral evolution and the health risks posed by obstructed airways? Sandra Kahn and Paul R. Ehrlich, a pioneering orthodontist and a world-renowned evolutionist, respectively, present the biological, dietary, and cultural changes that have driven us toward this major health challenge. They propose simple adjustments that can alleviate this developing crisis, as well as a major alternative to orthodontics that promises more significant long-term relief. Jaws will change your life. Every parent should read this book.

Download or read book Biology and Evolution of the Mexican Cavefish written by Alex Keene and published by Academic Press. This book was released on 2015-10-12 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biology and Evolution of the Mexican Cavefish features contributions by leading researchers in a comprehensive, unique work that examines a number of distinct areas of biology—evolution, development, ecology, and behavior—using the Mexican cavefish as a powerful model system to further understanding of basic biological processes such as eye degeneration, hearing, craniofacial development, sleep, and metabolic function. These fish are currently being used to better understand a number of issues related to human health, including age-related blindness, sleep, obesity, mood-related disorders, and aging. The recent sequencing of the cavefish genome broadens the interest of this system to groups working with diverse biological systems, and has helped researchers identify genes that regulate sleep, eye degeneration, and metabolic function. Mexican cavefish are particularly powerful for the study of biological processes because these fish evolved independently in twenty-nine caves in the Sierra de el Abra Region of Northeast Mexico. These fish have dramatic adaptations to the cave environment, and this can be used to identify genes involved in disease-related traits. This scholarly text will be of interest to researchers and students throughout diverse areas of biology and ecology. It includes photographs of animals and behavior in laboratory and natural settings that will also increase interest and accessibility to non-experts. Includes a mixture of images and illustrations such as the geographical distribution of cave pools and the developmental biology of the nervous system Features a companion site with geographical maps Fills a notable gap in the literature on a topic of broad interest to the scientific community Presents the recent sequencing of the cavefish genome as a groundbreaking development for researchers working with diverse biological systems

Download or read book Development Function and Evolution of Teeth written by Mark F. Teaford and published by Cambridge University Press. This book was released on 2007-02-01 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this field there has been an explosion of information generated by scientific research. One of the beneficiaries of this has been the study of morphology, where new techniques and analyses have led to insights into a wide range of topics. Advances in genetics, histology, microstructure, biomechanics and morphometrics have allowed researchers to view teeth from alternative perspectives. However, there has been little communication between researchers in the different fields of dental research. This book brings together overviews on a wide range of dental topics linking genes, molecules and developmental mechanisms within an evolutionary framework. Written by the leading experts in the field, this book will stimulate co-operative research in fields as diverse as paleontology, molecular biology, developmental biology and functional morphology.

Download or read book Orthodontics written by Thomas M. Graber and published by . This book was released on 1994 with total page 986 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition has been rewritten to reflect changes in the field. Concentrating on the most current concepts and best treatment methods in modern orthodontics, it provides an overview of diagnosis and treatment planning, followed by descriptions of orthodontic techniques.

Download or read book Evolution and Development of Fishes written by Zerina Johanson and published by Cambridge University Press. This book was released on 2019-01-10 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: World-class palaeontologists and biologists summarise the state-of-the-art on fish evolution and development.

Download or read book Teeth A Very Short Introduction written by Peter S. Ungar and published by OUP Oxford. This book was released on 2014-03-27 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Teeth are amazing - the product of half a billion years of evolution. They provide fuel for the body by breaking apart other living things; and they must do it again and again over a lifetime without themselves being broken in the process. This means that plants and animals have developed tough or hard tissues for protection, and teeth have evolved ways to sharpen or strengthen themselves to overcome those defences. And just as different jobs require different tools, animals with different diets have different shaped teeth to deal with the variety of foods that they eat. In this Very Short Introduction, Peter S. Ungar, an award-winning author and leading scientist, presents the story of teeth. Ungar outlines the key concepts, including insights into the origin of teeth and their evolution. Considering why teeth are important, he describes how they are made, and how they work, including their fundamental importance in the fossil record. Ungar finishes with a review of mammal teeth, looking at how they evolved and how recent changes to our diet are now affecting dental health. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

Download or read book Developmental Approaches to Human Evolution written by Julia C. Boughner and published by John Wiley & Sons. This book was released on 2016-01-22 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developmental Approaches to Human Evolution encapsulates the current state of evolutionary developmental anthropology. This emerging scientific field applies tools and approaches from modern developmental biology to understand the role of genetic and developmental processes in driving morphological and cognitive evolution in humans, non-human primates and in the laboratory organisms used to model these changes. Featuring contributions from well-established pioneers and emerging leaders, this volume is designed to build research momentum and catalyze future innovation in this burgeoning field. The book’s broad research scope encompasses soft and hard tissues of the head and body, including the skeleton, special senses and the brain. Developmental Approaches to Human Evolution is an invaluable resource on the mechanisms of primate and vertebrate evolution for scholars across a wide array of intersecting disciplines, including primatology, paleoanthropology, vertebrate morphology, evolutionary developmental biology and health sciences.

Download or read book Anthropological Perspectives on Tooth Morphology written by G. Richard Scott and published by Cambridge University Press. This book was released on 2013-02-21 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: This follow-up to The Anthropology of Modern Human Teeth puts methods to use in interpreting human origins and affinities.

Download or read book Mammal Teeth written by Peter S. Ungar and published by JHU Press. This book was released on 2010-10-01 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Winner, 2010 PROSE Award for Excellence in the Biological Sciences. Professional and Scholarly Publishing division of the Association of American Publishers In this unique book, Peter S. Ungar tells the story of mammalian teeth from their origin through their evolution to their current diversity. Mammal Teeth traces the evolutionary history of teeth, beginning with the very first mineralized vertebrate structures half a billion years ago. Ungar describes how the simple conical tooth of early vertebrates became the molars, incisors, and other forms we see in mammals today. Evolutionary adaptations changed pointy teeth into flatter ones, with specialized shapes designed to complement the corresponding jaw. Ungar explains tooth structure and function in the context of nutritional needs. The myriad tooth shapes produced by evolution offer different solutions to the fundamental problem of how to squeeze as many nutrients as possible out of foods. The book also highlights Ungar's own path-breaking studies that show how microwear analysis can help us understand ancient diets. The final part of the book provides an in-depth examination of mammalian teeth today, surveying all orders in the class, family by family. Ungar describes some of the more bizarre teeth, such as tusks, and the mammal diversity that accompanies these morphological wonders. Mammal Teeth captures the evolution of mammals, including humans, through the prism of dental change. Synthesizing decades of research, Ungar reveals the interconnections among mammal diet, dentition, and evolution. His book is a must-read for paleontologists, mammalogists, and anthropologists.

Download or read book Contemporary Orthodontics written by William R. Proffit and published by Mosby Elsevier Health Science. This book was released on 1993 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: William R. Profitt, DDS, PhD; with Henry W. Fields, Jr., DDS, MSD, and 4 contributors Content includes basic and applied growth and development, biomechanics and basic orthodontic techniques, and clinical orthodontics.

Download or read book Craniofacial Development written by Peter Thorogood and published by . This book was released on 1988 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dental Biomechanics written by Arturo N. Natali and published by CRC Press. This book was released on 2003-04-24 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dental Biomechanics provides a comprehensive, timely, and wide-reaching survey of the relevant aspects of biomechanical investigation within the dental field. Leading the reader through the mechanical analysis of dental problems in dental implants, orthodontics, and natural tooth mechanics, this book covers an increasingly important and popular sub

Download or read book Ten Cate s Oral Histology Pageburst on VitalSource written by Antonio Nanci and published by Elsevier Health Sciences. This book was released on 2007-09-26 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Take your understanding to a whole new level with Pageburst digital books on VitalSource! Easy-to-use, interactive features let you make highlights, share notes, run instant topic searches, and so much more. Best of all, with Pageburst, you get flexible online, offline, and mobile access to all your digital books. Understand oral histology and learn to apply your knowledge in the clinical setting with this definitive reference. Updated and enhanced, it provides insight on contemporary research and trends in oral histology, embryology, physiology, oral biology, and postnatal growth and development essential to your success in dentistry! Topics for Consideration boxes present expert perspectives on current trends and encourage additional research. Content outlines provide quick reference to specific topics within chapters. Logical organization enhances your understanding of chapter content and helps you review more effectively. Up-to-date recommended readings direct you to additional sources of relevant information. Concise, user-friendly writing style makes complex concepts easier to grasp. Companion CD includes over 300 multiple choice questions and over 100 labeling exercises that help you assess your comprehension and prepare for Part I of the board exam. Hundreds of full-color illustrations visually acquaint you with the oral structures and microscopic anatomy you'll encounter in dental care. Electronic image collection included on the companion CD is now in full-color, giving you clear, vibrant visual references for convenient study and review.

Download or read book The Anthropology of Modern Human Teeth written by G. Richard Scott and published by Cambridge University Press. This book was released on 2018-03-15 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: All humans share certain components of tooth structure, but show variation in size and morphology around this shared pattern. This book presents a worldwide synthesis of the global variation in tooth morphology in recent populations. Research has advanced on many fronts since the publication of the first edition, which has become a seminal work on the subject. This revised and updated edition introduces new ideas in dental genetics and ontogeny and summarizes major historical problems addressed by dental morphology. The detailed descriptions of 29 dental variables are fully updated with current data and include details of a new web-based application for using crown and root morphology to evaluate ancestry in forensic cases. A new chapter describes what constitutes a modern human dentition in the context of the hominin fossil record.