The book "The Genetical Theory of Natural Selection" by R. A. Fisher, published in 1930, explores the genetic basis of natural selection and its implications for evolutionary theory. Fisher argues that natural selection is not the same as evolution, and that the theory of natural selection has often been used as a convenient abbreviation for the theory of evolution by means of natural selection. He emphasizes the importance of independent study of natural selection, particularly in the context of genetics, which has advanced significantly since Darwin's time. Fisher discusses the particulate nature of inheritance, contrasting it with the blending theory proposed by Darwin. He explains how the particulate theory, which assumes that genetic traits are inherited as discrete units, resolves several difficulties faced by Darwin, such as the persistence of variability in domesticated species. Fisher also explores the concept of conservation of variance under particulate inheritance, which means that the variability within a population is maintained over time without diminishing. The book delves into the implications of particulate inheritance for theories of evolution, including the role of mutations and the mechanisms of natural selection. Fisher critiques various theories that rely on hypothetical agencies to direct the course of evolution, such as Lamarckian inheritance and environmental influences. He argues that these theories are less compelling when the particulate theory of inheritance is accepted. Fisher's work is significant for its rigorous mathematical treatment of genetic phenomena and its contribution to the understanding of the genetic basis of natural selection. The book includes detailed chapters on the nature of inheritance, the fundamental theorem of natural selection, the evolution of dominance, variation determined by mutation and selection, sexual reproduction and selection, mimicry, and the inheritance of human fertility.The book "The Genetical Theory of Natural Selection" by R. A. Fisher, published in 1930, explores the genetic basis of natural selection and its implications for evolutionary theory. Fisher argues that natural selection is not the same as evolution, and that the theory of natural selection has often been used as a convenient abbreviation for the theory of evolution by means of natural selection. He emphasizes the importance of independent study of natural selection, particularly in the context of genetics, which has advanced significantly since Darwin's time. Fisher discusses the particulate nature of inheritance, contrasting it with the blending theory proposed by Darwin. He explains how the particulate theory, which assumes that genetic traits are inherited as discrete units, resolves several difficulties faced by Darwin, such as the persistence of variability in domesticated species. Fisher also explores the concept of conservation of variance under particulate inheritance, which means that the variability within a population is maintained over time without diminishing. The book delves into the implications of particulate inheritance for theories of evolution, including the role of mutations and the mechanisms of natural selection. Fisher critiques various theories that rely on hypothetical agencies to direct the course of evolution, such as Lamarckian inheritance and environmental influences. He argues that these theories are less compelling when the particulate theory of inheritance is accepted. Fisher's work is significant for its rigorous mathematical treatment of genetic phenomena and its contribution to the understanding of the genetic basis of natural selection. The book includes detailed chapters on the nature of inheritance, the fundamental theorem of natural selection, the evolution of dominance, variation determined by mutation and selection, sexual reproduction and selection, mimicry, and the inheritance of human fertility.