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 Developmental Genetic Basis of Tooth Number Evolution in Stickleback Fish written by Phillip Alfonso Cleves and published by . This book was released on 2015 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Teeth are a classic model for studying vertebrate organogenesis and evolution. Despite the incredible phenotypic diversification of dentition in vertebrates, our understanding of the molecular and developmental basis behind this variation is limited. A derived benthic freshwater stickleback population has evolved a nearly two-fold increase in ventral pharyngeal tooth number compared to their ancestral marine counterparts. This evolved tooth gain provides an excellent system to study the developmental and molecular genetic basis of evolved dental variation. To ask when during development evolved tooth gain appears, we generated lab-reared developmental time courses of a low-toothed marine population and this high-toothed freshwater population. Early in development, no differences in dental patterning are observed. However, at late larval stages, an increase in tooth number, an increase in tooth plate area, and a decrease in tooth spacing arise. We identified genomic regions controlling these evolved patterning changes by mapping quantitative trait loci (QTL) controlling tooth number, area, and spacing in a marine by freshwater F2 cross. One large effect QTL controlling tooth number fine-maps to a genomic region containing an excellent candidate gene, Bone morphogenetic protein 6 (Bmp6). Stickleback Bmp6 is expressed in developing teeth, but no coding changes are found between the two populations. However, by quantitatively comparing allele specific expression of Bmp6, we find cis-regulatory changes have down-regulated the relative expression level of the freshwater Bmp6 allele at late, but not early, stages of development. To functionally test the role of Bmp6 in controlling tooth patterning, we generated predicted loss-of-function alleles of Bmp6 in freshwater sticklebacks. We found that Bmp6 is required for tooth formation and tooth plate area mirroring aspects of the evolved changes. Next, to discover enhancers that contain marine/freshwater sequence differences, we compared the chromosome 21 genomic sequences from fish with the tooth QTL to fish without the QTL. We identified a partially conserved region of the fourth intron of Bmp6 containing QTL-associated variants. This region is a tooth and fin enhancer that drives partially distinct expression patterns during tooth development compared to a 5' Bmp6 tooth and fin enhancer we previously discovered that lacks consistent sequence differences associated with the tooth QTL. Future genetic and transgenic approaches will functionally test this intron 4 enhancer of Bmp6 as a candidate for underlying evolved tooth gain in sticklebacks.

Download or read book Functional Genetic Analysis of Stickleback Craniofacial Evolution written by Priscilla Ashley Erickson and published by . This book was released on 2016 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The biosphere contains an incredible level of natural morphological diversity, and most differences within and between species can be explained by evolved differences in their genetic code. While traditional genetics has made great strides to connect genes to phenotypes in laboratory strains of model organisms, understanding the link between genotype and phenotype in natural populations is one of the greatest challenges of modern biology. Acquiring the genome sequences of organisms has been facilitated by rapidly advancing technologies, but connecting genetic variants to evolved differences remains elusive. What types of genetic changes underlie adaptive differences in morphology? How predictable is the path of evolution? Do individual mutations control multiple adaptive phenotypes? Answering these questions requires harnessing the power of modern genetics in a system with naturally evolved phenotypic variation. Chapter one outlines key questions in the fields of evolutionary developmental biology and adaptation genetics. It describes the cis-regulatory hypothesis for the genetic basis of morphological evolution and occurrence of supergenes that control multiple evolved phenotypes. It describes the natural history of the threespine stickleback fish and explains why the stickleback system is an outstanding model to tackle these questions. Gasterosteus aculeatus has adapted to unique habitats across the Northern Hemisphere and is amenable to both forward and reverse genetic studies. Marine and freshwater sticklebacks eat different foods and have different adaptations in the skeletal elements used to process food. Quantitative trait locus (QTL) mapping has demonstrated that a large number of genomic regions control the evolution of these skeletal traits, but a few key regions control a disproportionate number of traits. The following chapters investigate the developmental and genetic bases of two evolved skeletal changes that are controlled by the same genomic regions. Chapter two explores the genetic and developmental basis of the elongation of the branchial bones of the throat in freshwater sticklebacks. Elongation of these bones expands the buccal cavity, likely enabling freshwater fish to consume larger prey items. This increase in bone length is found in both wild and lab-reared fish from two populations, suggesting heritable convergent evolution in freshwater environments. In one population, an early increase in cartilage size contributes to increased bone length, and in both populations the bones grow faster throughout development. In both freshwater populations, the increase in bone length maps to two chromosomes: 4 and 21, with distinct effects of these two chromosomes on individual bones over the course of development, but similar effects in each cross. Collectively, these results suggest a largely parallel genetic and developmental basis of evolved bone length gain in two populations. Chapter three describes further mapping and functional testing of the chromosome 21 bone length QTL. While pharyngeal tooth gain maps to a regulatory haplotype of the gene Bone Morphogenetic Protein 6 (Bmp6), bone length gain maps to a nearby region containing the gene Tfap2a in two freshwater populations of sticklebacks. Therefore, evolved pharyngeal tooth gain and bone length gain are controlled by separate loci. Tfap2a is an important transcriptional regulator of craniofacial development and produces severe craniofacial phenotypes when mutated in vertebrates. In sticklebacks, the freshwater allele of Tfap2a is downregulated in the developing branchial skeleton of hybrid animals and deletion of Tfap2a causes a nearly complete absence of pharyngeal arch-derived skeletal elements. Heterozygous loss of Tfap2a alters branchial bone length, suggesting that dosage of this gene is important to determining bone patterning. Combined with previous findings in the lab, these results suggest that closely linked regulatory changes to two key developmental patterning genes produce skeletal gain phenotypes. Chapter four investigates the extent of genetic parallelism for repeated phenotypic evolution. In British Columbia, several lakes have independently evolved two freshwater stickleback ecotypes: a bottom-dwelling benthic form and an open-water limnetic form. Using crosses of benthic populations from three lakes, this study tests whether the genetic architecture underlying skeletal differences between benthic and marine individuals is repeatable across lakes. The majority of genomic regions underlying skeletal differences are unique to an individual lake, but there is more parallelism of QTL than expected by chance in simulations. Furthermore, the chromosome 21 QTL controlling bone length and tooth number were identified in multiple lakes, suggesting that these loci may be adaptive in the benthic habitat. These findings suggest that benthic evolution in three lakes has a significantly parallel but largely nonparallel basis. Chapter five examines the regulation of the gene Bmp6, which, like the bone length QTL, is found on chromosome 21 and likely underlies evolved tooth gain in sticklebacks via a cis-regulatory down-regulation of the freshwater allele. A short conserved regulatory element upstream of Bmp6 drives robust reporter gene expression during tooth development in both sticklebacks and distantly related zebrafish. This enhancer responds to TGFß signaling, likely via SMAD3 binding, and the enhancer is required for normal expression of Bmp6. Therefore, changes to additional regulatory loci controlling Bmp6 and interacting with this enhancer may underlie pharyngeal tooth number evolution. Finally, the future of stickleback molecular genetics will rely on functional genetic manipulations that will be facilitated by the emerging genome-editing revolution. The Appendix outlines a protocol for generating transgenic sticklebacks (carrying both transgenes and genome-edited alleles) using techniques developed and optimized over the course of the experiments described in chapters three and five. This protocol is intended to serve as a resource for the fish evolution and development community. Combined, the results described here offer several insights towards the molecular genetic and developmental basis of evolved skeletal change. Two adaptive alleles controlling related traits (tooth number and bone length gain) are found tightly linked in the genome, indicating that linkage of the QTL controlling these phenotypes may be adaptive for rapid colonization of freshwater habitats. Both QTL are associated with cis-regulatory down-regulation of candidate genes with highly pleiotropic roles during development. This finding suggests that skeletal gain traits may be readily accomplished by a loss of gene expression. Future studies will attempt to identify the causative mutations responsible for each trait and examine their frequencies and evolutionary histories in natural stickleback populations. Additional studies will attempt to identify the precise developmental effects of the regulatory mutations underlying the evolved differences.

Download or read book Genetic and Genomic Bases of Evolved Increases in Stickleback Dentition written by James Clinton Hart and published by . This book was released on 2018 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evolution - the great tinkerer - has produced the astounding diversity of form within and between existing species. It is a fundamental goal of evolutionary biology to understand the origin of such diversity. What types of genes underlie evolved changes in morphology? Are certain types of mutations (notably changes within regulatory regions) more likely to be used to produce adaptive changes in form? When distinct populations evolve similar morphological changes, are the underlying genetic bases changes to the same genes, the same genetic pathways, or largely independent? Are changes in form modular, or are their concerted changes to multiple developmentally similar organs? The ever cheapening cost of sequencing, coupled the availability of high-quality reference genomes, allows high-throughput approaches to identifying the loci of evolution. The emergence of a robust genome engineering system, CRISPR/Cas9, allows for efficient and direct testing of a gene's phenotype. Combining both of these techniques with a model system with naturally evolved phenotypic variation, the threespine stickleback, allows for systems-level answers to the many evolutionary questions. Chapter one outlines the field of evolutionary developmental biology. It proposes two alternative viewpoints for thinking about the evolution of form. The first is the view of the `Modern Synthesis', linking Mendelian inheritance with Darwinian natural selection, which explains evolution as the change in allele frequencies over time. The second views evolution through the lens of deep homology, focusing on changes to developmental programs over time, even across related organs within the same animal. It then introduces key concepts within evolutionary and developmental biology, including cis-regulation of gene expression, and gene regulatory networks. It then provides examples of evolution reusing similar gene regulatory networks, including Hox genes, Pax6 dependent eye initiation, and ectodermal placode development. Teeth use highly conserved signaling pathways, during both their initiation and replacement. Threespine sticklebacks Gasterosteus aculeatus have repeatedly adapted following a shift from marine to freshwater environments, with many independently derived populations sharing common morphological traits, including a gain in tooth number. The following chapters investigate this gain in tooth number in multiple distinct populations of sticklebacks. Chapter two describes the discovery and mapping of a spontaneous stickleback albino mutation, named casper. casper is a sex-linked recessive mutation that results in oculocutaneous albinism, defective swim bladders, and blood clotting defects. Bulked segregant mapping of casper mutants revealed a strong genetic signal on chromosome 19, the stickleback X chromosome, proximal to the gene Hps5. casper mutants had a unique insertion of a G in the 6th exon on Hps5. As mutants in the human orthologue of Hps5 resulted in similar albino and blood clotting phenotypes, Hps5 is a strong candidate underlying the casper phenotype. Further supporting this model, genome editing of Hps5 phenocopied casper. Lastly, we show that casper is an excellent tool for visualizing the activity of uorescent transgenes at late developmental stages due to the near-translucent nature of the mutant animals. Chapter three details the fine mapping of a quantitative trail locus (QTL) on chromosome 21 controlling increases in tooth number in a Canadian freshwater stickleback population. Recombinant mapping reduced the QTL-containing region to an 884kb window. Repeated QTL mapping experiments showed the presence of this QTL on multiple, but not all, wild derived chromosomes from the Canadian population. Comparative genome sequencing revealed the perfect correlation with genetic data of ten variants, spanning 4.4kb, all within the 4th intron of the gene Bmp6. Transgenic analysis of this intronic region uncovered its role as a robust tooth enhancer. TALEN induced mutations in Bmp6 revealed required roles for the gene in stickleback tooth development. Finally, comparative RNA-seq between Bmp6 wild-type and mutant dental tissue showed a loss of mouse hair stem cell genes in Bmp6 mutant fish teeth, suggesting deep homology of the regeneration of these two organs. Chapter four investigates the evolved changes in gene expression that accompany evolved increases in tooth number in two distinct freshwater populations. Independently derived stickleback populations from California and Canada have both evolved increases in tooth number, and previous work suggested that these populations used distinct genetic changes during their shared morphological changes. RNA-seq analysis of dental tissue from both freshwater populations compared to marine revealed a gain in critical regulators of tooth development in both freshwater populations. These evolved changes in gene expression can be partitioned in cis changes (mutations within regulatory elements of a gene) and trans changes (changes to the overall regulatory environment) using phased RNA-seq data from marine-freshwater F1 hybrids. Many genes show evidence for stabilizing selection of expression levels, with cis and trans changes in opposing directions. Most evolved changes in gene expression are due to changes in the trans environment, and these trans changes are more likely to be shared among the high-toothed freshwater populations. Thus, Californian and Canadian sticklebacks have convergently evolved similar trans regulatory environments through distinct cis regulatory changes. Chapter five identifies candidate genes underlying evolved tooth gain in multiple geographically distinct freshwater populations. Many populations of freshwater sticklebacks have evolved increases in both oral and pharyngeal tooth number. QTL mapping of this evolved gain in pharyngeal tooth number revealed that a 438bp regulatory haplotype of Bmp6 is associated with increased tooth number in five distinct Pacific Northwest populations, though not in the high-toothed California population. QTL mapping of evolved oral tooth gain in California reveals the surprisingly modular nature of evolved changes in dentition. Correlation analysis of gene expression data from 33 separate samples across multiple populations and genotypes revealed Plod2 and Pitx2 as dentally expressed candidate genes underlying evolved tooth gain. CRISPR/Cas9 genome editing of Plod2 resulted in mutants displaying increases in pharyngeal but decreases in oral tooth number. Mutations in Pitx2 are homozygous lethal and show a recessive near-complete loss of dentition across all tooth fields. The pleitropic effects of the coding mutations and the lack of evolved coding changes suggest that modular regulatory changes to Plod2 and Pitx2 underlie increases in tooth number. Combined, these results make significant contributions to our understanding of the evolutionary genetics underlying an adaptive change in morphology. Modular cis-regulatory alleles appear to play critical roles during the evolution of increased tooth number. Some alleles, such as the regulatory haplotype of Bmp6, are repeatedly used by multiple independently derived freshwater populations, suggesting both that the haplotype is adaptive and that evolution is partially repeatable. The Californian specific use of Plod2 and Pitx2 shows that evolution is not entirely predictable, and that there are many ways to modify teeth. Additionally, the use of high-throughput expression assays and genome sequencing, combined with genome editing with CRISPR/Cas9, allowed for rapid identification and testing of candidate genes underlying evolved changes in morphology. Additional studies could use these approaches to further identify the loci of evolved changes in morphology.

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 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 Diversity and Evolution of Butterfly Wing Patterns written by Toshio Sekimura and published by Springer. This book was released on 2017-08-29 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book facilitates an integrative understanding of the development, genetics and evolution of butterfly wing patterns. To develop a deep and realistic understanding of the diversity and evolution of butterfly wing patterns, it is essential and necessary to approach the problem from various kinds of key research fields such as “evo-devo,” “eco-devo,” ”developmental genetics,” “ecology and adaptation,” “food plants,” and “theoretical modeling.” The past decade-and-a-half has seen a veritable revolution in our understanding of the development, genetics and evolution of butterfly wing patterns. In addition, studies of how environmental and climatic factors affect the expression of color patterns has led to increasingly deeper understanding of the pervasiveness and underlying mechanisms of phenotypic plasticity. In recognition of the great progress in research on the biology, an international meeting titled “Integrative Approach to Understanding the Diversity of Butterfly Wing Patterns (IABP-2016)” was held at Chubu University, Japan in August 2016. This book consists of selected contributions from the meeting. Authors include main active researchers of new findings of corresponding genes as well as world leaders in both experimental and theoretical approaches to wing color patterns. The book provides excellent case studies for graduate and undergraduate classes in evolution, genetics/genomics, developmental biology, ecology, biochemistry, and also theoretical biology, opening the door to a new era in the integrative approach to the analysis of biological problems. This book is open access under a CC BY 4.0 license.

Download or read book Pyrosequencing Protocols written by Sharon Marsh and published by Springer Science & Business Media. This book was released on 2008-02-04 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents detailed protocols for the multidisciplinary application of Pyrosequencing® technology, all written by world-renowned experts. This comprehensive volume enables quick reference by collecting the primary applications for Pyrosequencing®, and supplementing each protocol with troubleshooting tips specific to that method. This volume both highlights the versatility of and provides detailed protocols for the application of Pyrosequencing®.

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 Evolutionary Biology of the Threespine Stickleback written by Michael A. Bell and published by Oxford University Press on Demand. This book was released on 1994 with total page 571 pages. Available in PDF, EPUB and Kindle. Book excerpt: The threespine stickleback is a small fish of temperate coastal and fresh waters that exhibits extraordinary phenotypic diversity. Benefiting from its amenability to observation in the field and manipulation in the laboratory, Niko Tinbergen pioneered the threespine stickleback's use in behavioral studies and established it as a model system in ethology. This up-to-date volume incorporates reviews from active researchers who use studies of the fish to address a broad variety of evolutionary issues, including optimal foraging, armor variation, speciation, and the endocrine basis for correlated behavioral characters. The work demonstrates the value of viewing the biology of a single organism simultaneously from multiple perspectives. Students and researchers in ecology, evolution, animal behavior, and vertebrate zoology will find much of interest in this useful book.

Download or read book The Evolution and Development of Mammalian Tooth Class written by Brooke Autumn Armfield and published by . This book was released on 2010 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: For centuries, the dentition has been important for morphological studies, while in the last twenty years teeth have become a model for epidermal organ development. By incorporating both morphological evidence and genetic knowledge to recreate the evolutionary pathways that led to certain tooth morphologies I hope to better understand the developmental mechanisms and the underlying evolutionary pattern observed in the teeth of mammals. For this dissertation, I examined protein and gene expression and interspecific morphometrics to evaluate theories on genetic control of dental patterns in three disparate mammals. First, tooth class in pigs was assessed by looking at gene expression patterns in a mammal with four distinct tooth types. Second a mammal with only one morphological tooth class, odontocetes (dolphins), was looked at to determine how protein expression patterns differ in a homodont mammal. To gain knowledge of the formation of the secondary teeth and the genes involved in determining their shape, I examined protein expression in the pig. I also analyzed integration patterns among primate teeth to determine if species-level morphologies can be explained by previous theories on how tooth class is established.

Download or read book Biology of the Three Spined Stickleback written by Sara Ostlund-Nilsson and published by CRC Press. This book was released on 2006-12-15 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Highlighting the growing importance of the sticklebacks as a model species in emerging fields such as molecular genetics, genomics, and environmental toxicology, Biology of the Three-Spined Stickleback examines data from researchers who use studies of the stickleback to address a wide range of biological issues. This state-of-the-art volume

Download or read book Mechanisms of Life History Evolution written by Thomas Flatt and published by OUP Oxford. This book was released on 2011-05-12 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: Life history theory seeks to explain the evolution of the major features of life cycles by analyzing the ecological factors that shape age-specific schedules of growth, reproduction, and survival and by investigating the trade-offs that constrain the evolution of these traits. Although life history theory has made enormous progress in explaining the diversity of life history strategies among species, it traditionally ignores the underlying proximate mechanisms. This novel book argues that many fundamental problems in life history evolution, including the nature of trade-offs, can only be fully resolved if we begin to integrate information on developmental, physiological, and genetic mechanisms into the classical life history framework. Each chapter is written by an established or up-and-coming leader in their respective field; they not only represent the state of the art but also offer fresh perspectives for future research. The text is divided into 7 sections that cover basic concepts (Part 1), the mechanisms that affect different parts of the life cycle (growth, development, and maturation; reproduction; and aging and somatic maintenance) (Parts 2-4), life history plasticity (Part 5), life history integration and trade-offs (Part 6), and concludes with a synthesis chapter written by a prominent leader in the field and an editorial postscript (Part 7).

Download or read book The Cichlid Fishes written by George Barlow and published by Basic Books. This book was released on 2008-12-15 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cichlid fishes are amazing creatures. In terms of sheer number of species, they are the most successful of all families of vertebrate animals, and the extent and speed with which they have evolved in some African lakes has made them the darlings of evolutionary biologists. But what truly captivates biologists like George Barlow -- not to mention thousands of aquarists the world over -- is the complexity of their social lives and their devotion to family (most species of cichlids are monogamous and many pairs share the responsibility of raising offspring). In this wonderful book, Barlow describes the unusually high intelligence of these fishes, their complex mating and parenting rituals, their bizarre feeding and fighting habits, and the unusual adaptations and explosive rate of speciation that have enabled them to proliferate and flourish. A celebration of their diversity, The Cichlid Fishes is also a marvelous exploration of how these unique animals might help resolve the age-old puzzle of how species arise and evolve.

Download or read book Morphological Integration written by Everett C. Olson and published by University of Chicago Press. This book was released on 1999-10 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite recent advances in genetics, development, anatomy, systematics, and morphometrics, the synthesis of ideas and research agenda put forth in the classic Morphological Integration remains remarkably fresh, timely, and relevant. Pioneers in reexamining morphology, Everett Olson and Robert Miller were among the first to explore the concept of the integrated organism in both living and extinct populations. In a new foreword and afterword, biologists Barry Chernoff and Paul Magwene summarize the landmark achievements made by Olson and Miller and bring matters discussed in the book up to date, suggest new methods, and accentuate the importance of continued research in morphological integration. Everett C. Olson was a professor at the University of Chicago and at the University of California, Los Angeles. He was a former president of the Society of Vertebrate Paleontology. Robert L. Miller was associate professor of geology at the University of Chicago, associate scientist in marine geology at the Woods Hole Oceanographic Institution, and a member of the board of editors of the Journal of Geology.

Download or read book The Shape of Life written by Rudolf A. Raff and published by University of Chicago Press. This book was released on 2012-12-14 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rudolf Raff is recognized as a pioneer in evolutionary developmental biology. In their 1983 book, Embryos, Genes, and Evolution, Raff and co-author Thomas Kaufman proposed a synthesis of developmental and evolutionary biology. In The Shape of Life, Raff analyzes the rise of this new experimental discipline and lays out new research questions, hypotheses, and approaches to guide its development. Raff uses the evolution of animal body plans to exemplify the interplay between developmental mechanisms and evolutionary patterns. Animal body plans emerged half a billion years ago. Evolution within these body plans during this span of time has resulted in the tremendous diversity of living animal forms. Raff argues for an integrated approach to the study of the intertwined roles of development and evolution involving phylogenetic, comparative, and functional biology. This new synthesis will interest not only scientists working in these areas, but also paleontologists, zoologists, morphologists, molecular biologists, and geneticists.

Download or read book Scientific American written by and published by . This book was released on 2008 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: