Population genetics hamilton pdf


    On this site you will find interactive computer simulations for each chapter, designed to show the fundamental concepts of population genetics. This book aims to make population genetics approachable, logicaland easily understood. To achieve these goals, the booksdesign emphasizes well explained. This book aims to make population genetics approachable, logical and easily understood. Dedicated website at lattrebmocheaga.cf This text.

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    Population Genetics Hamilton Pdf

    Population Genetics. Dedication. For my wife and best friend, I -Ling. Matthew B. Hamilton. @)WILEY-BLACKWELL. A John Wiley & Sons, Ltd., Publication. Hamilton, Matthew B. Population genetics / Matthew B. Hamilton. p. ; cm. Includes bibliographical references and index. ISBN (hbk. Request PDF on ResearchGate | Population Genetics are caused by population genetic mechanisms (Hartl and Clark, ; Hamilton, ).

    From the recurrence equations, it is easy to see that gametic and thus genotypic frequencies will be stable across generations, i. More precisely, linkage equilibrium means that the population-wide frequency of the AiBi gamete is equal to the frequency of the Ai allele multiplied by the frequency of the Bi allele. So a population initially in linkage disequilibrium will approach linkage equilibrium over a number of generations. The rate of approach depends on the value of r, the recombination fraction. Note the contrast with the one-locus case, where just one round of random mating is sufficient to bring the genotype frequencies into equilibrium. Population Genetics and its Critics The basic models of classical population genetics, expounded in the previous sections, have been around for nearly a century; they derive from the work of Fisher, Haldane and Wright in the s. Modern population genetics has built on this theoretical edifice in a number of ways, most notably by integrating the theory with data from molecular biology.

    Another point, not discussed above, is the fact that population genetics models are deliberately silent about the causes of the fitness differences between genotypes whose consequences they model Sober , Glymour For example, in the simple one-locus model of section 3. To fully understand evolution, the ecological factors that lead to these fitness differences must also be understood. While this is a valid point, the most it shows is that an exclusively population-genetic approach cannot yield a complete understanding of the evolutionary process.

    This does not really threaten the traditional view that population genetics is fundamental to evolutionary theory. A final suite of philosophical issues surrounding population genetics concerns causation.

    Population Genetics

    Evolutionary biology is standardly thought of as a science that yields causal explanations: it tells us the causes of particular evolutionary phenomena Okasha The basis for this way of speaking is obvious enough. If the frequency of gene A in a population increases from one generation to another, and if the population obeys the rules of Mendelian inheritance, then as a matter of logic one of three things must have happened: organisms bearing gene A must have outreproduced organisms without I ; organisms bearing gene A must have migrated into the population II ; or there must have been mutation to gene A from one of its alleles III.

    It is straightforward to verify that if none of I - III had happened, then the frequency of gene A would have been unchanged. Note that case I covers both selection and random drift, depending on whether the A and non-A organisms reproduced differentially because of their genotypic difference, or by chance. Despite this argument, a number of philosophers have objected to the idea that evolutionary change can usefully be thought of as caused by different factors, including natural selection e.

    Matthen and Ariew , Walsh The status of these objections is a controversial matter; see Reisman and Forber , Brandon and Ramsey and Sarkar for critical discussion. There is an important difference between drift on the other hand and the other three factors on the other. This is because mutation, selection and migration are directional; they typically lead to a non-zero expected change in gene frequencies Rice p.

    Random drift on the other hand is non-directional; the expected change due to drift is by definition zero. As Rice points out, this means that mutation, selection and migration can each be represented by a vector field on the space of gene frequencies; their combined effects on the overall evolutionary change is then represented by ordinary vector addition. But drift cannot be treated this way, for it has a magnitude but not a direction.

    However this line of argument is specific to random drift; it does not generalize to all the factors that affect gene frequency change.

    A related consideration is this. It is straightforward to verify that at least one of these three factors must have operated, if gene frequencies in a population change.

    It seems unproblematic to regard these three factors as causes of evolution. Rather, what we mean is that the differential reproduction was not the result of systematic differences in how well the genotypes were adapted to the environment. To conclude, it is unsurprising to find so much philosophical discussion of population genetics given its centrality to evolutionary biology, a science which has long attracted the attention of philosophers.

    The preceding discussion has focused on the most prominent debates surrounding population genetics in the recent philosophical literature; but in fact population genetics is relevant, at least indirectly, to virtually all of the topics traditionally discussed by philosophers of evolutionary biology.

    Bibliography Amundson, R.

    Beurton, P. Bowler, P. Reisman, K. Brandon, R. Hull and M. Ruse eds. The Cambridge Companion to the Philosophy of Biology, 66— Bromham, L. Carroll, S.

    Population Genetics | Human Genetics | Genetics | Life Sciences | Subjects | Wiley

    Crow, J. Darwin, C. Dawkins, R. Dietrich, M. Dunn, L. Edwards, A. Eldredge, N. Ewens, W. Falconer, D.

    Fisher, R. Frigg, R. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material.

    Abstract We describe the astonishing changes and progress that have occurred in the field of population genetics over the past 50 years, slightly longer than the time since the first Population Genetics Group PGG meeting in January We review the major questions and controversies that have preoccupied population geneticists during this time and were often hotly debated at PGG meetings.

    Population Genetics

    We show how theoretical and empirical work has combined to generate a highly productive interaction involving successive developments in the ability to characterise variability at the molecular level, to apply mathematical models to the interpretation of the data and to use the results to answer biologically important questions, even in nonmodel organisms.

    We also describe the changes from a field that was largely dominated by UK and North American biologists to a much more international one with the PGG meetings having made important contributions to the increased number of population geneticists in several European countries.

    Although we concentrate on the earlier history of the field, because developments in recent years are more familiar to most contemporary researchers, we end with a brief outline of topics in which new understanding is still actively developing. Introduction By , population genetics had accumulated a substantial body of mathematical theory stemming from the pioneering work of Fisher, Haldane and Wright, as well as a large amount of data from laboratory experiments on variation in components of fitness and other quantitative traits, and from studies of visible and chromosomal polymorphisms in natural populations, human blood groups as well as a handful of biochemical polymorphisms Lewontin, Ecological geneticists had demonstrated the action of selection on conspicuous polymorphisms such as the shell colour and banding variants of Cepaea nemoralis Ford, , and the sickle cell human haemoglobin variant had been shown to be maintained by heterozygote advantage caused by resistance to malaria Allison, Errata for first printing of Population Genetics.

    This file was last updated December 10, Download PopGeneS 2: This version may not install correctly on some versions of Windows 7. It has been successfully installed on Windows 8. The program PopGene. S2 is written in Microsoft visual basic and runs on Windows computers. The program requires a code library called. NET framework 2. Most Windows computers will require an update to.

    This update only needs to be installed once. Human Genetics The Quarterly Review of Biology 85 1: Simulations that demonstrate concepts in the text largely replacing PopGeneS2: