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Aging is one of those subjects that many biologists feel is largely unknown. Therefore, they often feel comfortable offering extremely facile generalizations that are either unsupported or directly refuted in the experimental literature. Despite this unfortunate precedent, aging is a very broad phenomenon that calls out for integration beyond the mere collecting together of results from disparate laboratory organisms. With this in mind, Part One offers several different synthetic perspectives. The editors, Rose and Finch, provide a verbal synthesis of the field that deliberately attempts to look at aging from both sides, the evolutionary and the molecular. The articles by Charlesworth and Clark both provide population- genetic perspectives on aging, the former more mathematical, the latter more experimental. Bell takes a completely different approach, arguing that aging may not be the result of evolutionary forces. Bell's model instead proposes that aging could arise from the progressive deterioration of chronic host- pathogen interactions. This is the first detailed publication of this model. It marks something of a return to the type of aging theories that predominated in the 1950's and 1960's, theories like the somatic mutation and error catastrophe theories. We hope that the reader will be interested by the contrast in views between the articles based on evolutionary theory and that of Bell. MR. Rose and C. E. Finch (eds. ), Genetics and Evolution of Aging, 5-12, 1994. (c) 1994 Kluwer Academic Publishers. The J aniform genetics of aging 2 Michael R. Rosel & Caleb E.
During the last 50 years, the perception oftransposable elements (TEs) has changed considerably from selfish DNA to sequences that may contribute significantly to genome function and evolution. The recent increased interest in TEs is based on the realization that they are a major genetic component (at least 10--20%) of all organisms and a major contributor to the mutation process. It is currently estimated that 70--80% of spontaneous mutations are the result of TE-mediated insertions, deletions, or chromosomal rearrangements. Thus, it seems at least plausible that TEs may playa significant role in the adaptation and evolution of natural populations and species. The ubiquity of TEs suggests that they are an old component of genomes which have been vertically transmitted through generations over evolutionary time. However, detailed analyses carried out over the last 20 years have revealed several unusual features of TE evolution: (i) TEs can be horizontally transferred between species; (ii) TE evolutionary rates can be dramatically increased by specific inactivation processes, such as the RIP (Repeat Induced Point mutation) mechanism in fungi; (iii) TEs can influence the regulation of other TEs by insertion or deletion; (iv) different classes of TEs in even distantly related species can be remarkably similar in both structure and function.
The ongoing debate on the use of DNA profiles to identify perpetrators in criminal investigations or fathers in paternity disputes has too often been conducted with no regard to sound statistical, genetic or legal reasoning. The contributors to Human Identification: The Use of DNA Markers all have considerable experience in forensic science, statistical genetics or jurimetrics, and many of them have had to explain the scientific issues involved in using DNA profiles to judges and juries. Although the authors hold differing views on some of the issues, they have all produced accounts which pay due attention to the, sometimes troubling, issues of independence of components of the profiles and of population substructures. The book presents the considerable evolution of ideas that has occurred since the 1992 Report of the National Research Council of the U.S. Audience: Indispensable to forensic scientists, laying out the concepts to all those with an interest in the use of genetic information. The chapters and exhaustive bibliography are vital information for all lawyers who must prosecute or defend DNA cases, and to judges trying such cases.
From topics like gonadal mosaicism and mutation clusters to adaptive mutagenesis, mutation in cell organelles, and the level and distribution of DNA molecular changes, the foundation is set for continuing the debate about the role of mutation, fitness, and adaptability.
In the second phase of new gene evolution, conventional models of new gene evolution, and systematical experimental pursuit of the origin and evolution of new gene functions did not appear for example by gene duplication, held that the muta until the early years of last decade.
From guppies to Galapagos finches and from adaptive landscapes to haldanes, this compilation of contributed works provides reviews, perspectives, theoretical models, statistical developments, and empirical demonstrations exploring the tempo and mode of microevolution on contemporary to geological time scales.
Genetic studies aimed at understanding the origin of species are dominating major scientific journals. This collection of papers discusses burgeoning genetic, evolutionary, and ecological approaches to understanding the origins of mating discrimination and causes of premating reproductive isolation both within and between species.
From topics like gonadal mosaicism and mutation clusters to adaptive mutagenesis, mutation in cell organelles, and the level and distribution of DNA molecular changes, the foundation is set for continuing the debate about the role of mutation, fitness, and adaptability.
During the last 50 years, the perception oftransposable elements (TEs) has changed considerably from selfish DNA to sequences that may contribute significantly to genome function and evolution. (iii) TEs can influence the regulation of other TEs by insertion or deletion;
Genetic studies aimed at understanding the origin of species are dominating major scientific journals. This collection of papers discusses burgeoning genetic, evolutionary, and ecological approaches to understanding the origins of mating discrimination and causes of premating reproductive isolation both within and between species.
In the second phase of new gene evolution, conventional models of new gene evolution, and systematical experimental pursuit of the origin and evolution of new gene functions did not appear for example by gene duplication, held that the muta until the early years of last decade.
In the summer of 1992 a distinguished group of molecular, population and evolutionary geneticists assembled on the campus of the University of Georgia in Athens, USA to discuss the relevance of their research to the role played by transposable elements (TEs) in evolution.
Drosophila melanogaster and Drosophila simulans are among the two sibling species for which a large set of data is available. In this book, ecologists, physiologists, geneticists, behaviorists share their data on the two sibling species, and put forward several scenarios of evolution to explain their similarities and divergences.
From guppies to Galapagos finches and from adaptive landscapes to haldanes, this compilation of contributed works provides reviews, perspectives, theoretical models, statistical developments, and empirical demonstrations exploring the tempo and mode of microevolution on contemporary to geological time scales.
Despite enormous efforts, over 100,000 papers and over $22 billion spent by the US taxpayer alone, the HIV-AIDS hypothesis has failed to produce any public health benefits, no vaccine, no effective drug, no prevention, no cure, not a single life saved.
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