Download or read book The Developmental Basis for the Evolution of Muroid Dentition written by Soile V. E. Keränen and published by . This book was released on 2000 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Evolution of the Rodents Volume 5 written by Philip G. Cox and published by Cambridge University Press. This book was released on 2015-08-06 with total page 627 pages. Available in PDF, EPUB and Kindle. Book excerpt: The widespread use of mouse models in developmental, behavioural and genetic studies has sparked wider interest in rodent biology as a whole. This book brings together the latest research on rodents to better understand the evolution of both living and extinct members of this fascinating group. Topics analysed include the role of molecular techniques in the determination of robust phylogenetic frameworks; how geometric morphometric methods help quantify and analyse variation in shape; and the role of developmental biology in elucidating the origins of skeletal elements and the teeth. The editors unite these disciplines to present the current state of knowledge in rodent biology, whilst setting the landscape for future research. This book highlights interdisciplinary links across palaeontology, developmental biology, functional morphology, phylogenetics and biomechanics, making it a valuable resource for evolutionary biologists in all fields.

Download or read book Hypsodonty in Mammals written by Richard H. Madden and published by Cambridge University Press. This book was released on 2015 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the central importance of soil ingestion and earth surface processes in driving the evolution of tooth shape in mammals.

Download or read book The Cambridge Handbook of Play written by Peter K. Smith and published by Cambridge University Press. This book was released on 2018-11-15 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Play takes up much of the time budget of young children, and many animals, but its importance in development remains contested. This comprehensive collection brings together multidisciplinary and developmental perspectives on the forms and functions of play in animals, children in different societies, and through the lifespan. The Cambridge Handbook of Play covers the evolution of play in animals, especially mammals; the development of play from infancy through childhood and into adulthood; historical and anthropological perspectives on play; theories and methodologies; the role of play in children's learning; play in special groups such as children with impairments, or suffering political violence; and the practical applications of playwork and play therapy. Written by an international team of scholars from diverse disciplines such as psychology, education, neuroscience, sociology, evolutionary biology and anthropology, this essential reference presents the current state of the field in play research.

Download or read book The Mammals of Luzon Island written by Lawrence R. Heaney and published by JHU Press. This book was released on 2016-04 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: A beautifully illustrated guide to the complete mammalian biodiversity of the Philippines’ largest island. Revealing the astounding mammalian diversity found on the largest Philippine island, The Mammals of Luzon Island is a unique book that functions both as a field guide and study of tropical fauna. The book features 120 fully illustrated species profiles and shows how the mammals fit into larger questions related to evolution, ecology, and biogeography. Luzon’s stunning variety of mammals includes giant fruit-eating bats; other bats so small that they can roost inside bamboo stems; giant plant-eating rodents that look like, but are not, squirrels; shrews that weigh less than half an ounce; the rapidly disappearing Philippine warty pig; and the long-tailed macaque, Luzon’s only nonhuman primate. While celebrating Luzon’s remarkably rich mammal fauna, the authors also suggest conservation strategies for the many species that are under threat from a variety of pressures. Based on a century of accumulated data and fifteen years of intensive study, The Mammals of Luzon Island delivers a message that will appeal equally to scientists, conservationists, and ecologically minded travelers.

Download or read book Odontogenesis written by and published by . This book was released on 2000 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Evolutionary Relationships among Rodents written by W. Patrick Luckett and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: The order Rodentia is the most abundant and successful group of mammals, and it has been a focal point of attention for compar ative and evolutionary biologists for many years. In addition, rodents are the most commonly used experimental mammals for bio medical research, and they have played a central role in investi gations of the genetic and molecular mechanisms of speciation in mammals. During recent decades, a tremendous amount of new data from various aspects of the biology of living and fossil rodents has been accumulated by specialists from different disciplines, ranging from molecular biology to paleontology. Paradoxically, our understanding of the possible evolutionary relationships among different rodent families, as well as the possible affinities of rodents with other eutherian mammals, has not kept pace with this information "explosion. " This abundance of new biological data has not been incorporated into a broad synthesis of rodent phylo geny, in part because of the difficulty for any single student of rodent evolution to evaluate the phylogenetic significance of new findings from such diverse disciplines as paleontology, embryology, comparative anatomy, molecular biology, and cytogenetics. The origin and subsequent radiation of the order Rodentia were based primarily on the acquisition of a key character complex: specializations of the incisors, cheek teeth, and associated mus culoskeletal features of the jaws and skull for gnawing and chewing.

Download or read book Molecular Evolution written by Roderick D.M. Page and published by John Wiley & Sons. This book was released on 2009-07-14 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of evolution at the molecular level has given the subject of evolutionary biology a new significance. Phylogenetic 'trees' of gene sequences are a powerful tool for recovering evolutionary relationships among species, and can be used to answer a broad range of evolutionary and ecological questions. They are also beginning to permeate the medical sciences. In this book, the authors approach the study of molecular evolution with the phylogenetic tree as a central metaphor. This will equip students and professionals with the ability to see both the evolutionary relevance of molecular data, and the significance evolutionary theory has for molecular studies. The book is accessible yet sufficiently detailed and explicit so that the student can learn the mechanics of the procedures discussed. The book is intended for senior undergraduate and graduate students taking courses in molecular evolution/phylogenetic reconstruction. It will also be a useful supplement for students taking wider courses in evolution, as well as a valuable resource for professionals. First student textbook of phylogenetic reconstruction which uses the tree as a central metaphor of evolution. Chapter summaries and annotated suggestions for further reading. Worked examples facilitate understanding of some of the more complex issues. Emphasis on clarity and accessibility.

Download or read book Mammalian Sexuality written by Alan F. Dixson and published by Cambridge University Press. This book was released on 2021-06-03 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first detailed account of post-copulatory sexual selection and the evolution of reproduction in mammals.

Download or read book Carnivore Behavior Ecology and Evolution written by John L. Gittleman and published by Cornell University Press. This book was released on 2019-05-15 with total page 639 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mammalian order Carnivora is characterized by an incredible range of morphological, ecological, and behavioral variation. Carnivores can be as small as the 100-gram least weasel or as large as the 800-kilogram polar bear. Their reproductive rate can vary from one offspring every five years, as with some black bears, to three litters a year, as with the dwarf mongoose. Group sizes can be traced along a wide continuum, from the solitary ermine to the monogamous golden jackal to the large extended packs of as many as 80 spotted hyenas. Until recently the general habits of most wild carnivore species were inadequately understood. In the last decade, however, improved technologies, including the use of radiotelemetry and night-vision scopes, have led to many important discoveries. This book is at once a critical summary and an evaluation of current research on carnivores. A worthy successor to R.F. Ewer's monumental volume, The Carnivores (Cornell University Press), it is the work of 30 leading carnivore biologists, who here assemble comparative data on the basic anatomical, behavioral, ecological, physiological, reproductive, and evolutionary characteristics of this group. After a general introduction to the Carnivora, the volume is divided in three parts, each of which begins with a brief introduction outlining its main themes. Part I, Behavior, covers acoustic and olfactory communication, behavioral development, behavioral ecology of canids and hyaenids, modes of solitary living, and group living. In Part II, Ecology, topics include feeding ecology of the giant panda and Asiatic black bear, adatpations for aquatic living, ecological constraints on predation in felids, consequences of small size in mustelids, rate of basal metabolism and food habits, and reproductive output. Part III, Evolution, deals with the morphological approaches to phylogeny, and the fossil record. An appendix presents a complete classification of the Carnivora, including topics of continuing controversy. Highlighting recent developments in the study of the Carnivora and areas for further research, this broad synthesis will be of great value of students and researchers in animal behavior, behavioral ecology, wildlife ecology, mammalogy, paleontology, systematics, and evolution theory. It will also encourage realistic conservation programs to manage rapidly diminishing populations and will elucidate particular features of the carnivores for nonspecialist readers.

Download or read book Annals of the Carnegie Museum written by Carnegie Museum and published by . This book was released on 1990 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Teeth of Mammalian Vertebrates written by Barry Berkovitz and published by Academic Press. This book was released on 2018-08-10 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Teeth of Mammalian Vertebrates is an important reference for researchers in dentistry, comparative morphology, anthropology, and vertebrate palaeontology, and those with an interest in exploring and understanding diversity. The book provides a comprehensive and informed analysis of mammalian dentitions and highlights the importance of teeth as drivers and mirrors of evolution and diversity." - Journal of Anatomy The Teeth of Mammalian Vertebrates presents a comprehensive survey of mammalian dentitions that is based on material gathered from museums and research workers from around the world. The teeth are major factors in the success of mammals, and knowledge of tooth form and function is essential in mammalian biology. Illustrated with high-quality color photographs of skulls and dentitions, together with X-rays, CT images and histology, this book reveals the tremendous variety of tooth form and structure in mammals. Written by two internationally-recognized experts in dental anatomy, the book provides an up-to-date account of how teeth are adapted to acquiring and processing food. With its companion volume, this book provides a complete survey of the teeth of vertebrates. It is the ideal resource for students and researchers in zoology, biology, anthropology, archaeology and dentistry. Provides a comprehensive account of mammalian dentitions, together with helpful reading lists Illustrated by 900 high-quality photographs, X-rays, CT scans and histological images from leading researchers and world class museum collection Depicts lateral and occlusal views of the skull and dentition, which conveys a much greater level of morphological detail than line drawings Contains clear-and-concise, up-to-date reviews of the structure and properties of dental tissues, especially the enamel and tooth support system, both of which play vital roles in the functioning of the mammalian dentition

Download or read book Some Tertiary Mammals and Birds from North America written by Carnegie Institution of Washington and published by . This book was released on 1949 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phylogenetic Relationships of Oryzomine Rodents Muroidea Sigmodontinae written by Marcelo Weksler and published by . This book was released on 2006 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study I provide a phylogenetic hypothesis for the tribe Oryzomyini that can be used to understand the diversification and evolution of this group of rodents and to revise the current generic-level classification. Morphological and molecular data were used for these purposes in combined and separate analyses. Molecular data consisted of partial sequences (1266 bp) from the first exon of the nuclear gene encoding the interphotoreceptor retinoid binding protein (IRBP); the morphological matrix comprised 99 characters, including 16 integumental characters, 32 skull characters, 29 dental characters, 7 postcranial characters, and 10 characters from the phallus and soft-anatomy systems. I present anatomical descriptions for each character, including delineation of different states observed among oryzomyines. Results of the combined analysis were congruent with the IRBP-only dataset for oryzomyine higher-level relationships. Morphological analyses, although showing discrepancies from the combined or IRBP consensus cladograms and with low nodal support values, recovered several clades similar to the combined and IRBP analyses. Systematics of the tribe and the evolution of a few pivotal characters are discussed in light of the proposed phylogeny. Different taxonomic arrangements for species currently included in the genus Oryzomys are suggested. Finally, I evaluate evolutionary and biogeographic hypotheses that are compatible with our current knowledge on oryzomyine relationships.

Download or read book The Timetree of Life written by S. Blair Hedges and published by OUP Oxford. This book was released on 2009-04-23 with total page 1237 pages. Available in PDF, EPUB and Kindle. Book excerpt: The evolutionary history of life includes two primary components: phylogeny and timescale. Phylogeny refers to the branching order (relationships) of species or other taxa within a group and is crucial for understanding the inheritance of traits and for erecting classifications. However, a timescale is equally important because it provides a way to compare phylogeny directly with the evolution of other organisms and with planetary history such as geology, climate, extraterrestrialimpacts, and other features.The Timetree of Life is the first reference book to synthesize the wealth of information relating to the temporal component of phylogenetic trees. In the past, biologists have relied exclusively upon the fossil record to infer an evolutionary timescale. However, recent revolutionary advances in molecular biology have made it possible to not only estimate the relationships of many groups of organisms, but also to estimate their times of divergence with molecular clocks. The routineestimation and utilization of these so-called 'time-trees' could add exciting new dimensions to biology including enhanced opportunities to integrate large molecular data sets with fossil and biogeographic evidence (and thereby foster greater communication between molecular and traditional systematists). Theycould help estimate not only ancestral character states but also evolutionary rates in numerous categories of organismal phenotype; establish more reliable associations between causal historical processes and biological outcomes; develop a universally standardized scheme for biological classifications; and generally promote novel avenues of thought in many arenas of comparative evolutionary biology.This authoritative reference work brings together, for the first time, experts on all major groups of organisms to assemble a timetree of life. The result is a comprehensive resource on evolutionary history which will be an indispensable reference for scientists, educators, and students in the life sciences, earth sciences, and molecular biology. For each major group of organism, a representative is illustrated and a timetree of families and higher taxonomic groups is shown. Basic aspects ofthe evolutionary history of the group, the fossil record, and competing hypotheses of relationships are discussed. Details of the divergence times are presented for each node in the timetree, and primary literature references are included. The book is complemented by an online database(www.timetree.net) which allows researchers to both deposit and retrieve data.