|
Gene-centered View Of Evolution
The gene-centered view of evolution, gene's eye view, gene selection theory, or selfish gene theory holds that adaptive evolution occurs through the differential survival of competing genes, increasing the allele frequency of those alleles whose phenotypic trait effects successfully promote their own propagation. The proponents of this viewpoint argue that, since heritable information is passed from generation to generation almost exclusively by DNA, natural selection and evolution are best considered from the perspective of genes. Proponents of the gene-centered viewpoint argue that it permits understanding of diverse phenomena such as altruism and intragenomic conflict that are otherwise difficult to explain from an organism-centered viewpoint. Some proponents claim that the gene-centered view is the aspect of evolutionary theory that is the most empirically validated, has the greatest predictive power, and has the broadest applicability. The gene-centered view of evolut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution
Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation. The scientific theory of evolution by natural selection was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace, in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book ''On the Origin of Species''. Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) phenotypic variatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selfish Genetic Element
Selfish genetic elements (historically also referred to as selfish genes, ultra-selfish genes, selfish DNA, parasitic DNA and genomic outlaws) are genetic segments that can enhance their own transmission at the expense of other genes in the genome, even if this has no positive or a net negative effect on organismal fitness. Genomes have traditionally been viewed as cohesive units, with genes acting together to improve the fitness of the organism. Early observations of selfish genetic elements were made almost a century ago, but the topic did not get widespread attention until several decades later. Inspired by the gene-centred views of evolution popularized by George Williams and Richard Dawkins, two papers were published back-to-back in ''Nature'' in 1980 – by Leslie Orgel and Francis Crick and by Ford Doolittle and Carmen Sapienza – introducing the concept of selfish genetic elements (at the time called "selfish DNA") to the wider scientific community. Both papers emphasi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unit Of Selection
A unit of selection is a biological entity within the hierarchy of biological organization (for example, an entity such as: a self-replicating molecule, a gene, a cell, an organism, a group, or a species) that is subject to natural selection. There is debate among evolutionary biologists about the extent to which evolution has been shaped by selective pressures acting at these different levels.Okasha, S. (2006) ''Evolution and the levels of selection''. Oxford University Press. There is debate over the relative importance of the units themselves. For instance, is it group or individual selection that has driven the evolution of altruism? Where altruism reduces the fitness of ''individuals'', individual-centered explanations for the evolution of altruism become complex and rely on the use of game theory, for instance; see kin selection and group selection. There also is debate over the definition of the units themselves, and the roles for selection and replication, and whether ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Dawkins Cooper Union Shankbone
Richard is a male given name. It originates, via Old French, from Old Frankish and is a compound of the words descending from Proto-Germanic language">Proto-Germanic Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the linguistic reconstruction, reconstructed proto-language of the Germanic languages, Germanic branch of the Indo-European languages. Proto-Germanic eventually developed from ... ''*rīk-'' 'ruler, leader, king' and ''*hardu-'' 'strong, brave, hardy', and it therefore means 'strong in rule'. Nicknames include "Richie", "Dick (nickname), Dick", "Dickon", "Dickie (name), Dickie", "Rich (given name), Rich", "Rick (given name), Rick", "Rico (name), Rico", "Ricky (given name), Ricky", and more. Richard is a common English (the name was introduced into England by the Normans), German and French male name. It's also used in many more languages, particularly Germanic, such as Norwegian, Danish, Swedish, Icelandic, and Dutch, as well as other languag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epigenetics
In biology, epigenetics is the study of changes in gene expression that happen without changes to the DNA sequence. The Greek prefix ''epi-'' (ἐπι- "over, outside of, around") in ''epigenetics'' implies features that are "on top of" or "in addition to" the traditional (DNA sequence based) genetic mechanism of inheritance. Epigenetics usually involves a change that is not erased by cell division, and affects the regulation of gene expression. Such effects on cellular and physiological traits may result from environmental factors, or be part of normal development. The term also refers to the mechanism of changes: functionally relevant alterations to the genome that do not involve mutation of the nucleotide sequence. Examples of mechanisms that produce such changes are DNA methylation and histone modification, each of which alters how genes are expressed without altering the underlying DNA sequence. Further, non-coding RNA sequences have been shown to play a key role in the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sewall Wright
Sewall Green Wright ForMemRS HonFRSE (December 21, 1889March 3, 1988) was an American geneticist known for his influential work on evolutionary theory and also for his work on path analysis. He was a founder of population genetics alongside Ronald Fisher and J. B. S. Haldane, which was a major step in the development of the modern synthesis combining genetics with evolution. He discovered the inbreeding coefficient and methods of computing it in pedigree animals. He extended this work to populations, computing the amount of inbreeding between members of populations as a result of random genetic drift, and along with Fisher he pioneered methods for computing the distribution of gene frequencies among populations as a result of the interaction of natural selection, mutation, migration and genetic drift. Wright also made major contributions to mammalian and biochemical genetics. Biography Sewall Wright was born in Melrose, Massachusetts, to Philip Green Wright and Elizabe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Genetical Theory Of Natural Selection
''The Genetical Theory of Natural Selection'' is a book by Ronald Fisher which combines Mendelian inheritance, Mendelian genetics with Charles Darwin's theory of natural selection, with Fisher being the first to argue that "Mendelism therefore validates Darwinism" and stating with regard to mutations that "The vast majority of large mutations are deleterious; small mutations are both far more frequent and more likely to be useful", thus refuting orthogenesis. First published in 1930 by Oxford University Press#Clarendon Press, The Clarendon Press, it is one of the most important books of the Modern synthesis (20th century), modern synthesis, and helped define population genetics. It had been described by James F. Crow, J. F. Crow as the "deepest book on evolution since Darwin". It is commonly cited in biology books, outlining many concepts that are still considered important such as Fisherian runaway, Fisher's principle, Reproductive value (population genetics), reproductive value, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mendelian Genetics
Mendelian inheritance (also known as Mendelism) is a type of biological inheritance following the principles originally proposed by Gregor Mendel in 1865 and 1866, re-discovered in 1900 by Hugo de Vries and Carl Correns, and later popularized by William Bateson. These principles were initially controversial. When Mendel's theories were integrated with the Boveri–Sutton chromosome theory of inheritance by Thomas Hunt Morgan in 1915, they became the core of classical genetics. Ronald Fisher combined these ideas with the theory of natural selection in his 1930 book '' The Genetical Theory of Natural Selection'', putting evolution onto a mathematical footing and forming the basis for population genetics within the modern evolutionary synthesis. History The principles of Mendelian inheritance were named for and first derived by Gregor Johann Mendel, a nineteenth-century Moravian monk who formulated his ideas after conducting simple hybridization experiments with pea plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistics
Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a scientific, industrial, or social problem, it is conventional to begin with a statistical population or a statistical model to be studied. Populations can be diverse groups of people or objects such as "all people living in a country" or "every atom composing a crystal". Statistics deals with every aspect of data, including the planning of data collection in terms of the design of statistical survey, surveys and experimental design, experiments. When census data (comprising every member of the target population) cannot be collected, statisticians collect data by developing specific experiment designs and survey sample (statistics), samples. Representative sampling assures that inferences and conclusions can reasonably extend from the sample ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ronald Fisher
Sir Ronald Aylmer Fisher (17 February 1890 – 29 July 1962) was a British polymath who was active as a mathematician, statistician, biologist, geneticist, and academic. For his work in statistics, he has been described as "a genius who almost single-handedly created the foundations for modern statistical science" and "the single most important figure in 20th century statistics". In genetics, Fisher was the one to most comprehensively combine the ideas of Gregor Mendel and Charles Darwin, as his work used mathematics to combine Mendelian genetics and natural selection; this contributed to the revival of Darwinism in the early 20th-century revision of the theory of evolution known as the Modern synthesis (20th century), modern synthesis. For his contributions to biology, Richard Dawkins declared Fisher to be the greatest of Darwin's successors. He is also considered one of the founding fathers of Neo-Darwinism. According to statistician Jeffrey T. Leek, Fisher is the most in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maynard Smith
John Maynard Smith (6 January 1920 – 19 April 2004) was a British theoretical and mathematical evolutionary biologist and geneticist. Originally an aeronautical engineer during the Second World War, he took a second degree in genetics under the biologist J. B. S. Haldane. Maynard Smith was instrumental in the application of game theory to evolution with George R. Price, and theorised on other problems such as the evolution of sex and signalling theory. Biography Early years John Maynard Smith was born in London, the son of the surgeon Sidney Maynard Smith, but following his father's death in 1928, the family moved to Exmoor, where he became interested in natural history. Quite unhappy with the lack of formal science education at Eton College, Maynard Smith took it upon himself to develop an interest in Darwinian evolutionary theory and mathematics, after having read the work of old Etonian J. B. S. Haldane, whose books were in the school's library despite the bad r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Dogma Of Molecular Biology
The central dogma of molecular biology deals with the flow of genetic information within a biological system. It is often stated as "DNA makes RNA, and RNA makes protein", although this is not its original meaning. It was first stated by Francis Crick in 1957, then published in 1958: He re-stated it in a ''Nature'' paper published in 1970: "The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information. It states that such information cannot be transferred back from protein to either protein or nucleic acid." A second version of the central dogma is popular but incorrect. This is the simplistic DNA → RNA → protein pathway published by James Watson in the first edition of ''The Molecular Biology of the Gene'' (1965). Watson's version differs from Crick's because Watson describes a two-step (DNA → RNA and RNA → protein) process as the central dogma. While the dogma as originally stated by Crick remains valid today, Wat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
