Download or read book Mod le de d veloppement et volution du patron dentaire chez les rongeurs actuels et fossiles written by Gaëlle Labonne and published by . This book was released on 2014 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'évolution de la dentition des mammifères se caractérise par d'importantes innovations morphologiques comme la mise à occlusion et l'hétérodontie. Parmi rongeurs, dont la formule dentaire est fortement réduite, les arvicolinés possèdent une dentition hautement dérivée, avec des molaires prismatiques et hypsodontes. L'objectif de cette thèse est d'explorer les différentes innovations morphologiques de la dentition au travers des aspects développementaux et adaptatifs. Les méthodes de morphométrie géométrique sont utilisées sur les molaires, les incisives et les mandibules afin d'explorer les dynamiques de développement et d'évolution de la dentition. Un modèle développemental permettant de prédire les proportions de molaires inférieures est examiné et validé à l'échelle de l'ordre des rongeurs ; il peut également être étendu à la prémolaire. De plus, le lien entre la morphologie dentaire, notamment les proportions de molaires, et le régime alimentaire est complexe, un caractère morphologique ne reflétant pas directement une alimentation. Cependant les covariations entre les molaires marquent le mouvement de mastication et ainsi la fonction. Nos résultats confirment une imbrication complexe des contraintes historiques, fonctionnelles et développementales dans l'interprétation des morphologies. Les différentes composantes de la mandibule présentent une organisation hiérarchique complexe. Le développement de la dentition des mammifères est gouverné par des processus similaires mais des mécanismes tels que l'hétérochronie ont pu conduire à une diversification des phénotypes au cours du temps.
Download or read book Evo D vo des dents chez les rongeurs murin s written by Cyril Charles and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Au sein des mammifères, les dents constituent un modèle idéal pour étudier les mécanismes liant évolution et biologie du développement. De nombreux gènes impliqués dans le développement dentaire ont été identifiés chez la souris. Cependant, leur implication dans les processus d’évolution reste en grande partie à étudier. Le présent travail a pour objectif d’évaluer le rôle de certains gènes dans l’évolution des dents chez les mammifères, plus particulièrement chez les rongeurs Muroidea. Dans une première partie, des anomalies dentaires rapportées dans des populations naturelles de mammifères sont présentées et discutées en regard des modèles de développement dentaire. Ces anomalies permettent également de souligner les différentes tendances évolutives chez les euthériens. La deuxième partie de ce travail comprend une étude des phénotypes dentaires associés aux pertes de fonctions de deux gènes de la voie Eda (Eda, Edar). L’étude de ces mutants permet d'apporter de nouvelles informations sur le rôle de ces gènes au cours du développement. Les résultats montrent également que la voie Eda est potentiellement impliquée dans l'évolution des rongeurs, en particulier dans l'acquisition de la formule dentaire des Muroidea. Les comparaisons morphologiques entre les mutants de la voie Eda et des espèces actuelles indiquent également une implication possible de cette voie de signalisation pour la mise en place de la morphologie dentaire particulière de Rhynchomys (Muridae, Rodentia). Enfin, une étude préliminaire de la morphologie dentaire des souris avec des pertes de fonction du gène Fgf3 et de ses antagonistes, Sprouty2 et Sprouty4, indique une implication potentielle de ces gènes pour l'acquisition du plan dentaire murin ainsi que des similitudes avec des espèces de Muridae primitifs. L’ensemble des résultats indique donc que les gènes du développement sélectionnés pour ce travail sont potentiellement impliqués dans l'évolution des dents des rongeurs Muroidea.
Download or read book Mammals of Algeria written by Kazimierz Kowalski and published by . This book was released on 1991 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Master of the River written by Félix Antoine Savard and published by . This book was released on 1976 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dictionary of the French and English Languages written by Gabriel Surenne and published by . This book was released on 1856 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Wild Mammals of Japan written by Satoshi D. Ohdachi and published by . This book was released on 2009 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Pocket Dictionary of the French and English Languages in Two Parts written by Thomas Nugent and published by . This book was released on 1770 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conservation de la For t Dense en Afrique Centrale Et de L Ouest written by Kevin M. Cleaver and published by World Bank Publications. This book was released on 1992 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume brings together selected papers presented and discussed at the Conference on Conservation of West and Central African Rainforests, held in Abidjan, November 5-9, 1990.
Download or read book The Biology of Chameleons written by Krystal A. Tolley and published by Univ of California Press. This book was released on 2013-11-16 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: They change color depending on their mood. They possess uniquely adapted hands and feet distinct from other tetrapods. They feature independently movable eyes. This comprehensive volume delves into these fascinating details and thorough research about one of the most charismatic families of reptilesÑChameleonidae. Written for professional herpetologists, scholars, researchers, and students, this book takes readers on a voyage across time to discover everything that is known about chameleon biology: anatomy, physiology, adaptations, ecology, behavior, biogeography, phylogeny, classification, and conservation. A description of the natural history of chameleons is given, along with the fossil record and typical characteristics of each genus. The state of chameleons in the modern world is also depicted, complete with new information on the most serious threats to these remarkable reptiles.
Download or read book Feeding in Vertebrates written by Vincent Bels and published by Springer. This book was released on 2019-04-23 with total page 865 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Ecology and Biomechanics written by Anthony Herrel and published by CRC Press. This book was released on 2006-01-13 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: We live in a well-engineered universe. This engineering is present in every system and organism in existence, including in the actions and interactions of plants and animals. In fact, one could say that the function and movement of plants and animals is just as much a part of their makeup as chlorophyll and fiber or bone and blood. Consequently, if
Download or read book A Phonetic Dictionary of the English Language written by Hermann Michaelis and published by . This book was released on 1913 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Carnivorous Dinosaurs written by Kenneth Carpenter and published by Indiana University Press. This book was released on 2005-07-07 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: The meat-eating dinosaurs, or Theropoda, include some of the fiercest predators that ever lived. Some of the group's members survive to this day—as birds. The theropod/bird connection has been explored in several recent works, but this book presents 17 papers on a variety of other topics. It is organized into three parts. Part I explores morphological details that are important for understanding theropod systematics. Part II focuses on specific regions of theropod anatomy and biomechanics. Part III examines various lines of evidence that reveal something about theropods as living creatures. The contributors are Ronan Allain, Rinchen Barsbold, Kenneth Carpenter, Karen Cloward, Rodolfo A. Coria, Philip J. Currie, Peter M. Galton, Robert Gay, Donald M. Henderson, Dong Huang, James I. Kirkland, Yoshitsugu Kobayashi, Eva B. Koppelhus, Peter Larson, Junchang Lü, Lorrie A. McWhinney, Clifford Miles, Ralph E. Molnar, N. Murphy, John H. Ostrom, Gregory S. Paul, Licheng Qiu,J. Keith Rigby, Jr., Bruce Rothschild, Christopher B. Ruff, Leonardo Salgado, Frank Sanders, Julia T. Sankey, Judith A. Schiebout, David K. Smith, Barbara R. Standhardt, Kathy Stokosa, Darren H. Tanke, François Therrien, David Trexler, Kelly Wicks, Douglas G. Wolfe, and Lowell Wood.
Download or read book Biology of Turtles written by Jeanette Wyneken and published by CRC Press. This book was released on 2007-12-26 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Featuring in-depth contributions from an international team of experts, the Biology of Turtles provides the first comprehensive review of the Testudinata. The book starts with the premise that the structure of turtles is particularly interesting and best understood within the context of their development, novelty, functional diversity, and e
Download or read book Creating Futures written by Michel Godet and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Africa s Critical Choices written by Dunod Editeur and published by Europa Regional Perspectives. This book was released on 2019 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume examines contemporary Africa, a vast continent which, while entering the era of globalization, is also confronted by a number of issues, including the environment and climate change, demographics, trade issues, internal and external migration, education, economic Issues, governance, and the influence of other countries. Written by former Prime Minister of Niger and current Chief Executive Officer of the Secretariat of the New Partnership for Africa's Development (NEPAD), Dr Ibrahim Assane Mayaki, this book offers an overview of Africa, and looks to the next generation of leaders in the continent, aiming to offer a manifesto for future change.
Download or read book Historical Dictionary of Iran written by John Henry Lorentz and published by Historical Dictionaries of Asia, Oceania, and the Middle East. This book was released on 2007 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an overview of specific events, movements, people, political and social groups, places, trends, and chronology. Allows for considerable exploration of a number of historical and contemporary topics and issues. The modern period, defined as 1800-present, is covered extensively.
