Tracing the development of population genetics through the writings of such luminaries as Darwin, Galton, Pearson, Fisher, Haldane, and Wright, William B. Provine sheds light on this complex field as well as its bearing on other branches of biology.

This book covers those areas of theoretical population genetics that can be investigated rigorously by elementary mathematical methods. I have tried to formulate the various models fairly generally and to state the biological as sumptions quite explicitly. I hope the choice and treatment of topics will en able the reader to understand and evaluate detailed analyses of many specific models and applications in the literature. Models in population genetics are highly idealized, often even over idealized, and their connection with observation is frequently remote. Further more, it is not practicable to measure the parameters and variables in these models with high accuracy. These regrettable circumstances amply justify the use of appropriate, lucid, and rigorous approximations in the analysis of our models, and such approximations are often illuminating even when exact solu tions are available. However, our empirical and theoretical limitations justify neither opaque, incomplete formulations nor unconvincing, inadequate analy ses, for these may produce uninterpretable, misleading, or erroneous results. Intuition is a principal source of ideas for the construction and investigation of models, but it can replace neither clear formulation nor careful analysis. Fisher (1930; 1958, pp. x, 23-24, 38) not only espoused similar ideas, but he recognized also that our concepts of intuition and rigor must evolve in time. The book is neither a review of the literature nor a compendium of results. The material is almost entirely self-contained. The first eight chapters are a thoroughly revised and greatly extended version of my published lecture notes (Nagylaki, 1977a).

The advances made possible by the development of molecular techniques have in recent years revolutionized quantitative genetics and its relevance for population genetics. Population Genetics and Microevolutionary Theory takes a modern approach to population genetics, incorporating modern molecular biology, species-level evolutionary biology, and a thorough acknowledgment of quantitative genetics as the theoretical basis for population genetics. Logically organized into three main sections on population structure and history, genotype-phenotype interactions, and selection/adaptation Extensive use of real examples to illustrate concepts Written in a clear and accessible manner and devoid of complex mathematical equations Includes the author's introduction to background material as well as a conclusion for a handy overview of the field and its modern applications Each chapter ends with a set of review questions and answers Offers helpful general references and Internet links

The rise of the neutral theory of molecular evolution seems to have aroused a renewed interest in mathematical population genetics among biologists, who are primarily experimenters rather than theoreticians. This has encouraged me to set out the mathematics of the evolutionary process in a manner that, I hope, will be comprehensible to those with only a basic knowledge of calculus and matrix algebra. I must acknowledge from the start my great debt to my students. Equipped initially with rather limited mathematics, they have pursued the subject with much enthusiasm and success. This has enabled me to try a number of different approaches over the years. I was particularly grateful to Dr L. J. Eaves and Professor W. E. Nance for the opportunity to give a one-semester course at the Medical College of Virginia, and I would like to thank them, their colleagues and their students for the many kindnesses shown to me during my visit. I have concentrated almost entirely on stochastic topics, since these cause the greatest problems for non-mathematicians. The latter are particularly concerned with the range of validity of formulae. A sense of confidence in applying these formulae is, almost certainly, best gained by following their derivation. I have set out proofs in fair detail, since, in my experience, minor points of algebraic manipulation occasionally cause problems. To avoid loss of continuity, I have sometimes put material in notes at the end of chapters.

To show the importance of stochastic processes in the change of gene frequencies, the authors discuss topics ranging from molecular evolution to two-locus problems in terms of diffusion models. Throughout their discussion, they come to grips with one of the most challenging problems in population genetics--the ways in which genetic variability is maintained in Mendelian populations. R.A. Fisher, J.B.S. Haldane, and Sewall Wright, in pioneering works, confirmed the usefulness of mathematical theory in population genetics. The synthesis their work achieved is recognized today as mathematical genetics, that branch of genetics whose aim is to investigate the laws governing the genetic structure of natural populations and, consequently, to clarify the mechanisms of evolution. For the benefit of population geneticists without advanced mathematical training, Professors Kimura and Ohta use verbal description rather than mathematical symbolism wherever practicable. A mathematical appendix is included.

This volume emphasizes the period before 1950. During this period Wright thought of himself primarily as an experimental physiological geneticist rather than as a theoretical population geneticist.

"Provine's thorough and thoroughly admirable examination of Wright's life and influence, which is accompanied by a very useful collection of Wright's papers on evolution, is the best we have for any recent figure in evolutionary biology."—Joe Felsenstein, Nature "In Sewall Wright and Evolutionary Biology . . . Provine has produced an intellectual biography which serves to chart in considerable detail both the life and work of one man and the history of evolutionary theory in the middle half of this century. Provine is admirably suited to his task. . . . The resulting book is clearly a labour of love which will be of great interest to those who have a mature interest in the history of evolutionary theory."-John Durant, ;ITimes Higher Education Supplement;X

One of this century's leading evolutionary biologists, Motoo Kimura revolutionized the field with his random drift theory of molecular evolution—the neutral theory—and his groundbreaking theoretical work in population genetics. This volume collects 57 of Kimura's most important papers and covers forty years of his diverse and original contributions to our understanding of how genetic variation affects evolutionary change. Kimura's neutral theory, first presented in 1968, challenged the notion that natural selection was the sole directive force in evolution. Arguing that mutations and random drift account for variations at the level of DNA and amino acids, Kimura advanced a theory of evolutionary change that was strongly challenged at first and that eventually earned the respect and interest of evolutionary biologists throughout the world. This volume includes the seminal papers on the neutral theory, as well as many others that cover such topics as population structure, variable selection intensity, the genetics of quantitative characters, inbreeding systems, and reversibility of changes by random drift. Background essays by Naoyuki Takahata examine Kimura's work in relation to its effects and recent developments in each area.

genetics. " It is simply the appropriation of that term, very likely with insufficient knowledge and respect for its past usage. For that, the Editor alone is responsible and requests tolerance. He has, as far as he can tell, no intention or desire to use it for any historiographical purposes other than that just mentioned. Even more important, the decision to consider Muller together with Fisher, Haldane and Wright is also not original. Crow (1984) has already done so, arguing persua sively that Muller was "keenly interested in evolution and made sub stantial contributions to the development of the neo-Darwinian view. " Crow's reasons for considering these four figures together and the reasons discussed above are complementary. This book continues a historiographical choice he initiated; others will have to judge whether it is appropriate. The foregoing considerations were intended to show why Fisher, Haldane, Muller and Wright should be considered together in the history of theoretical evolutionary genetics. I By a welcome stroke of luck, from the point of view of the Editor, all four of these figures were born almost together, between 1889 and 1892, and almost exactly a century ago. It therefore seemed appropriate to use their birth cente naries to consider their work together. A conference was held at Boston University, on March 6, 1990, under the auspices of the Boston Center for the Philosophy and History of Science, to discuss their work. This book has emerged mainly from that conference.