Download or read book Sex Reversal in the Alpine Skink Bassiana Duperreyi written by Duminda S.B.D.D. Mudiyanselage and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Global climatic change has significant impacts on several aspects of the biology and ecology of many reptile species on earth, which in some cases has led to population declines or other severe threats. Until now, however, such impacts have not been reviewed for many reptiles, even though these species are often at the critical stage at the conservation priorities. Changing temperature is increasingly being considered one of the major threats for reptiles, especially for species where temperature extremes can influence the outcome of sex determination. In reptiles, sex can be determined genetically (genotypicsex determination or GSD) or environmentally, depending on their incubation temperature (temperature sex determination or TSD). Typically, the two alternatives of sex determination were thought to be incompatible and were never observed in the same species, however sex reversal of some GSD species under extreme environmental conditions, confirmed in wild populations, has revealed that intermediate states are possible. Sex determination in the endemic Australian skink Bassiana duperreyi is influenced by both genetic factors and nest temperature. The discordance between genotypic and phenotypic was observed definitively in the laboratory conditions. Whether sex reversal occurs in natural nests and whether sex-reversed individuals survive to adulthood in wild populations is unknown. Furthermore, it is unclear whether the interaction of sex reversal of male XX individuals under low temperatures occurs at a rate sufficient to trigger loss of the Y chromosome and evolutionary transitions between GSD and TSD. To address these questions in the wild population of B. duperreyi, we first developed reliable molecular techniques to identify sex reversal male (XX) from normal male (XY), is known as in silico whole-genome subtraction. We used this technique to isolate seven Y chromosome specific markers for B. duperreyi. In chapter 3, using these markers, we demonstrated that sex reversal in the wild for the first time in adults of a reptile species with XX/XY sex determination. The highest frequency of sex reversal occurred at the highest coolest elevation location, Mt Ginini (18.46%) and decreased in frequency to zero with decreasing elevation. We model the impact of this under Fisher's frequency-dependent selection to show that, at the highest elevations, populations risk the loss of the Y chromosome and a transition to temperature-dependent sex determination. We also applied our Y chromosome markers to hatchlings, in chapter 5, similar to what we discovered in adults, we discovered that the levels of sex reversal in nests of B. duperreyi, ranged from 28.6% at the highest, coolest locations to zero at the lowest, warmest locations. Further, we observed that the constant temperature equivalent in wild nests dropped below the 20°C during the thermosensitive period, for even for a short time during the incubation period, sex reversal was observed. Therefore, extreme cold temperature events might lead to 100% sex reversal of the XX genotype in the alpine populations. The variation in the frequency of sex reversal in B. duperreyi as a phenotypicresponse to environmental temperature with altitude, and early work using mtDNA has raised the possibility that underlying phylogenetic history may be confounding interpretation of variation in the frequency of sex reversal with elevation. To test this, in chapter 4, we examined the underlying genetic structure within the geographic wide populations on its distribution used single nucleotide polymorphisms (SNP) generated by reduced representation sequencing. We generated 12,532 reliable polymorphic SNP loci from 60 populations (263 individuals) covering the distribution of B. duperreyi to assessgene flow and to define population structure in the form of diagnosable lineages. We identified five well-supported diagnosable operational taxonomic units (OTUs) within B. duperreyi. Low levels of divergence of B. duperreyi between mainland Australia and Tasmania (no fixed allelic differences) support the notion of episodic exchange of alleles across Bass Strait (ca 60 m, 25 Kya) during periods of low sea level during the Upper Pleistocene rather than the much longer period of isolation (1.7 My) indicated by earlier studies using mitochondrial sequence variation. Our study provides foundational work forthe detailed taxonomic re-evaluation of this species complex and the need for biodiversity assessment to include an examination of cryptic species and/or cryptic diversity below the level of species. This thesis contributes to our understanding of the risks of population demography due to climate change in species subject to sex reversal by temperature, and sex reversal in this alpine skink makes it a sensitive indicator of climate change, both in terms of changes in average temperatures, and in terms of climatic variability will provide focus for future research to test on-the-ground management strategies to mitigate the effects of climate in local populations. Further, we provide evidence that sex reversal by cool temperatures in B. duperreyi occurs in the wild, influences the sexual genotypes-phenotype combinations in adult populations, and is as such a potential means of rapid evolutionary responses to climate change.
Download or read book Applied Environmental Genomics written by Oliver F... Berry and published by CSIRO PUBLISHING. This book was released on 2023-12 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: DNA is the essence of life and the original ‘big data’. New technologies are allowing scientists to access and make sense of this information like never before, and they are using it to solve the world’s greatest environmental challenges. Applied Environmental Genomics synthesises the latest and most exciting uses of genomic technologies for environmental science and management. With an emphasis on diversity of applications and real-world demonstrations, leading researchers have contributed detailed chapters on innovative approaches to obtaining critical management-relevant information about the natural world. These chapters are complemented by perspective sections written by environmental managers who describe their experiences using genomics to support evidence-based decisions. Ideal for students, researchers and professionals working in natural resource management and policy, Applied Environmental Genomics is a comprehensive introduction to a fast-moving field that is transforming the practice of environmental management, with profound relevance to industry, government and the public.
Download or read book Temperature Dependent Sex Determination in Vertebrates written by Nicole Valenzuela and published by Smithsonian Institution Scholarly Press. This book was released on 2004 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edited by the world's foremost authorities on the subject, with essays by leading scholars in the field, this work shows how the sex of reptiles and many fish is determined not by the chromosomes they inherit but by the temperature at which incubation takes place.
Download or read book Ecology Abstracts written by and published by . This book was released on 2000 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coverage: 1982- current; updated: monthly. This database covers current ecology research across a wide range of disciplines, reflecting recent advances in light of growing evidence regarding global environmental change and destruction. Major ares of subject coverage include: Algae/lichens, Animals, Annelids, Aquatic ecosystems, Arachnids, Arid zones, Birds, Brackish water, Bryophytes/pteridophytes, Coastal ecosystems, Conifers, Conservation, Control, Crustaceans, Ecosyst em studies, Fungi, Grasses, Grasslands, High altitude environments, Human ecology, Insects, Legumes, Mammals, Management, Microorganisms, Molluscs, Nematodes, Paleo-ecology, Plants, Pollution studies, Reptiles, River basins, Soil, TAiga/tundra, Terrestrial ecosystems, Vertebrates, Wetlands, Woodlands.
Download or read book The Action Plan for Australian Lizards and Snakes 2017 written by Nicola Mitchell and published by CSIRO PUBLISHING. This book was released on 2019-12-01 with total page 1378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lizards and snakes (squamate reptiles) are the most diverse vertebrate group in Australia, with approximately 1000 described species, representing about 10% of the global squamate diversity. Squamates are a vital part of the Australian ecosystem, but their conservation has been hindered by a lack of knowledge of their diversity, distribution, biology and key threats. The Action Plan for Australian Lizards and Snakes 2017 provides the first comprehensive assessment of the conservation status of Australian squamates in 25 years. Conservation assessments are provided for 986 species of Australian lizards and snakes (including sea snakes). Over the past 25 years there has been a substantial increase in the number of species and families recognised within Australia. There has also been an increase in the range and magnitude of threatening processes with the potential to impact squamates. This has resulted in an increase in the proportion of the Australian squamate fauna that is considered Threatened. Notably over this period, the first known extinction (post-European settlement) of an Australian reptile species occurred – an indication of the increasingly urgent need for better knowledge and management of this fauna. Six key recommendations are presented to improve the conservation management and plight of Australian squamates. This Action Plan represents an essential resource for research scientists, conservation biologists, conservation managers, environmental consultants, policy makers from Commonwealth and State/Territory governments, and the herpetological community.
Download or read book Escaping From Predators written by William E. Cooper, Jr and published by Cambridge University Press. This book was released on 2015-05-28 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: When a predator attacks, prey are faced with a series of 'if', 'when' and 'how' escape decisions – these critical questions are the foci of this book. Cooper and Blumstein bring together a balance of theory and empirical research to summarise over fifty years of scattered research and benchmark current thinking in the rapidly expanding literature on the behavioural ecology of escaping. The book consolidates current and new behaviour models with taxonomically divided empirical chapters that demonstrate the application of escape theory to different groups. The chapters integrate behaviour with physiology, genetics and evolution to lead the reader through the complex decisions faced by prey during a predator attack, examining how these decisions interact with life history and individual variation. The chapter on best practice field methodology and the ideas for future research presented throughout, ensure this volume is practical as well as informative.
Download or read book Pheromones and Reproduction written by Yasuhiko Sagara and published by Parthenon Publishing. This book was released on 1990 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecological Impacts of Firewood Collection written by Geoff Brown and published by . This book was released on 2010 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The review is to inform the development of a Victorian statewide strategy that ensures that firewood supply from public land has a sustainable future"--Summary.
Download or read book Reptiles and Amphibians of Australia written by Harold Cogger and published by CSIRO PUBLISHING. This book was released on 2018-10-01 with total page 1093 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reptiles and Amphibians of Australia is a complete guide to Australia’s rich and varied herpetofauna, including frogs, crocodiles, turtles, tortoises, lizards and snakes. For each of the 1218 species there is a description of its appearance, distribution and habits. These descriptions are also accompanied by distribution maps and, in many cases, one of the book's more than 1000 colour photographs of living animals. The book also includes 130 simple-to-use dichotomous keys, accompanied by hundreds of explanatory drawings, that in most cases allow a specimen in hand to be identified. In addition, it has a comprehensive list of scientific references for those wishing to conduct more in-depth research, an extensive glossary, and basic guides to the collection, preservation and captive care of specimens. This classic work was originally published in 1975. The updated seventh edition contains a new Appendix that discusses recent changes and lists over 80 new or resurrected species and genera that have been added to the Australian frog and reptile fauna since the 2014 edition.
Download or read book Evolution of Sex Determining Mechanisms written by James J. Bull and published by Benjamin-Cummings Publishing Company. This book was released on 1983 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sex Control in Aquaculture written by Hanping Wang and published by John Wiley & Sons. This book was released on 2018-11-08 with total page 1969 pages. Available in PDF, EPUB and Kindle. Book excerpt: Awarded Bookauthority's "Best Aquaculture Books of all Time" A comprehensive resource that covers all the aspects of sex control in aquaculture written by internationally-acclaimed scientists Comprehensive in scope, Sex Control in Aquaculture first explains the concepts and rationale for sex control in aquaculture, which serves different purposes. The most important are: to produce monosex stocks to rear only the fastest-growing sex in some species, to prevent precocious or uncontrolled reproduction in other species and to aid in broodstock management. The application of sex ratio manipulation for population control and invasive species management is also included. Next, this book provides detailed and updated information on the underlying genetic, epigenetic, endocrine and environmental mechanisms responsible for the establishment of the sexes, and explains chromosome set manipulation techniques, hybridization and the latest gene knockout approaches. Furthermore, the book offers detailed protocols and key summarizing information on how sex control is practiced worldwide in 35 major aquaculture species or groups, including fish and crustaceans, and puts the focus on its application in the aquaculture industry. With contributions from an international panel of leading scientists, Sex Control in Aquaculture will appeal to a large audience: aquaculture/fisheries professionals and students, scientists or biologists working with basic aspects of fish/shrimp biology, growth and reproductive endocrinology, genetics, molecular biology, evolutionary biology, and R&D managers and administrators. This text explores sex control technologies and monosex production of commercially-farmed fish and crustacean species that are highly in demand for aquaculture, to improve feed utilization efficiency, reduce energy consumption for reproduction and eliminate a series of problems caused by mixed sex rearing. Thus, this book: Contains contributions from an international panel of leading scientists and professionals in the field Provides comprehensive coverage of both established and new technologies to control sex ratios that are becoming more necessary to increase productivity in aquaculture Includes detailed coverage of the most effective sex control techniques used in the world's most important commercially-farmed species Sex Control in Aquaculture is the comprehensive resource for understanding the biological rationale, scientific principles and real-world practices in this exciting and expanding field.
Download or read book Reproductive and Developmental Strategies written by Kazuya Kobayashi and published by Springer. This book was released on 2018-06-01 with total page 783 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides new insights into the universality of biological systems in animal reproduction and development by a comparative study of a variety of mechanisms in animals ranging from basal invertebrates to vertebrates, including mammals. Animals accomplish genetic diversity through meiosis and fertilization, and during embryogenesis animals must produce specialized cell types, including germ cells, in accordance with their individual body plan. This series of phenomena is essential to the continuity of life in the animal kingdom, and animals show various reproductive and developmental strategies. This volume, comprising four parts, reviews animal kingdom diversity, including reproductive strategies and germ cell differentiation mechanisms (Part 1), sex determination and differentiation (Part2), the mechanisms of fertilization (Part 3), and body axis formation (Part 4). Readers will find descriptions of the reproduction or development of 180 species, 13 phyla, 35 classes, 74 orders, 117 families, and 151 genera in this book. Of particular interest is the diversity of molecules and mechanisms used to achieve the same biological purpose in different animals. Undergraduates, graduate students, and professional scientists who want a deeper understanding of animal reproductive and developmental mechanisms will find this book to be of great value.
Download or read book Reptiles of Australia written by Harold G. Cogger and published by . This book was released on 1980 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reptilian Incubation written by Denis Charles Deeming and published by . This book was released on 2004-01-01 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reptiles have been a topic for scientific study for many decades and remain widely studied around the world. In particular, their reproductive patterns and strategies have been extensively studied, proving useful in analysis of life-history strategies. A pivotal aspect of reptilian reproduction is incubation of eggs. Oviparity is found in all turtles, crocodilians and the tuatara and is prevalent in many lizards and snakes. Many aspects of the eggs, embryos and incubation conditions have been the subject of numerous scientific reports. This volume is dedicated to systematic analysis of reptilian incubation. The concept for the book is to look at reptilian eggs, development and incubation conditions in a functional way with particular emphasis on the natural incubation environment and, rather than concentrating on Family accounts, (e.g. incubation in crocodilians) the chapters review the topics in all reptile types allowing for the first time a systematic comparison of incubation between crocodilians, turtles and squamates. In addition to reviewing current information, the authors briefly look towards the future and outline areas where further research is needed.
Download or read book Eucalypt Ecology written by Jann Elizabeth Williams and published by Cambridge University Press. This book was released on 1997-11-13 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dominant trees of Australia, eucalypts make up a remarkable genus. This authoritative volume provides current reviews by active researchers of many disciplines, including evolutionary history, genetics, distribution and modelling, the relationship of eucalypts to fire and nutrients, ecophysiology, pollination and reproductive ecology, interactions between eucalypts and other co-existing biota (including fungi, invertebrates and vertebrates), and conservation and management. Together these reviews shed light on the reasons for the great success of eucalypts in Australian environments, and provide a comprehensive summary for comparison with the ecology of major woody plant genera in other continents. This volume is of particular relevance to Australian ecologists, but also provides a stimulating perspective to students of vegetation ecology in all continents.
Download or read book Atlas of Amphibians and Reptiles in Europe written by Jean-Pierre Gasc and published by Muséum National d'Histoire Naturelle. This book was released on 2004 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: Présente la répartition géographique, la taxinomie, l'état de la population et les problèmes de conservation des espèces d'amphibiens et de reptiles en Europe.
Download or read book Snakes written by Richard A. Seigel and published by . This book was released on 2001 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, first published in 1987 and here reprinted with a new foreword by the authors has become a classic in the field of herpetology. In ecological and evolutionary research snakes occupy a unique niche. Studies of their adaptations and life histories have broad applications for the most basic questions in biology. This book fills the need for an up-to-date text/reference in the growing field of snake ecology and evolutionary biology. Here, in one volume is an extensive review of the biology of these fascinating reptiles, including topics such as zoogeography, fossil history, systematics, foraging and reproduction. With contributions from many leading herpetologists, the work is divided into sections on Systematics and Morphology, Methods and Techniques and Life History and Ecology. Each section summarizes what is known about these major fields of snake biology. This book serves the needs of those actively involved in research as well as the amateur naturalist and the beginning student. Dr. Richard A. Seigel became interested in herpetology while an undergraduate at Rutgers University, where he received his B.A. in Zoology and Physiology in 1977. He continued his work with amphibians and reptiles while getting his M.S. in Biological Sciences from the University of Central Florida in 1979 and his Ph.D. from the University of Kansas in 1984. He is currently Full Professor and Chair of the Department of Biological Sciences at Towson University in Maryland. Dr. Siegel's primary research interests are in the population ecology and conservation biology of amphibians and reptiles. He has published over 50 peer-reviewed papers and has co-authored or edited four texts on the ecology and biology of snakes. From 1993-2000, he was the Editor-in-Chief of the Journal of Herpetology, the largest international publication in its field. Joseph T. Collins has written more than 200 articles on reptiles, amphibians, and fishes throughout North America and twenty-three books, including: Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America Third Edition (with Roger Conant), Amphibians and Reptiles in Kansas Third Edition (with photographs by Suzanne L. Collins), Natural Kansas, An Illustrated Guide to Endangered or Threatened Species in Kansas, (with Suzanne L. Collins, Jerry Horak, Dan Mulhern, William H. Busby, Craig C. Freeman, and Gary Wallace), A Key to Amphibians and Reptiles of the Continental United States and Canada (with Robert Powell and Errol D. Hooper, Jr.). In 1978, Collins served as president of the Society for the Study of Amphibians and Reptiles, the leading international professional society in that field, as president of the Kansas Association of Biology Teachers (1980-1981) and as president of the Kansas Herpetological Society. He was a distinguished delegate to the First World Congress of Herpetology at Canterbury, England in 1989, and was made a Distinguished Life Member of the Kansas Herpetological Society in 1998. Susan S. Novak, a native of Chicago, has been a Lawrence, Kansas, resident since 1986. Novak has been an editor of scientific/technical, scholarly, and popular work for twenty years, working formerly as the editor at the Savannah River Ecology Laboratory. She joined the staff of the Kansas State Historical Society in 1993, where she has since served as the managing editor of Kansas Heritage magazine and the associate editor of Kansas History: A Journal of the Central Plains, providing regular departments, main articles, photographs, book reviews, and layout and design work.
