|
The Apportionment Of Human Diversity
"The Apportionment of Human Diversity" is a 1972 paper on racial categorisation by American evolutionary biologist Richard Lewontin. In it, Lewontin presented an analysis of genetic diversity amongst people from different conventionally-defined races. His main finding, that there is more genetic variation within these populations than between them, is considered a landmark in the study of human genetic variation and contributed to the abandonment of race as a scientific concept. Background By the 1960s, anthropologists such as Frank B. Livingstone had concluded that "there are no races, there are only clines" – smooth gradients of genetic variation in a species across its geographic range. Lewontin's mentor Theodosius Dobzhansky challenged this, arguing that there are human discrete populations that can be distinguished by differences in the frequency of genetic traits, which he called races. At that time the debate was largely semantic, stemming from their different ideas ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Race (human Categorization)
Race is a categorization of humans based on shared physical or social qualities into groups generally viewed as distinct within a given society. The term came into common usage during the 16th century, when it was used to refer to groups of various kinds, including those characterized by close kinship relations. By the 17th century, the term began to refer to physical ( phenotypical) traits, and then later to national affiliations. Modern science regards race as a social construct, an identity which is assigned based on rules made by society. While partly based on physical similarities within groups, race does not have an inherent physical or biological meaning. The concept of race is foundational to racism, the belief that humans can be divided based on the superiority of one race over another. Social conceptions and groupings of races have varied over time, often involving folk taxonomies that define essential types of individuals based on perceived traits. Modern scienti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fixation Index
The fixation index (FST) is a measure of population differentiation due to genetic structure. It is frequently estimated from Polymorphism (biology), genetic polymorphism data, such as single-nucleotide polymorphisms (SNP) or Microsatellite (genetics), microsatellites. Developed as a special case of Sewall WWright's F-statistics, it is one of the most commonly used statistics in population genetics. Its values range from 0 to 1, with 0 being no differentiation and 1 being complete differentiation. Interpretation This comparison of genetic variability within and between populations is frequently used in applied population genetics. The values range from 0 to 1. A zero value implies complete panmixia; that is, that the two populations are interbreeding freely. A value of one implies that all genetic variation is explained by the population structure, and that the two populations do not share any genetic diversity. For idealized models such as Isolation_by_distance#Sewall_Wright-_Ec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biology Papers
Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, origin, evolution, and distribution of life. Central to biology are five fundamental themes: the cell as the basic unit of life, genes and heredity as the basis of inheritance, evolution as the driver of biological diversity, energy transformation for sustaining life processes, and the maintenance of internal stability (homeostasis). Biology examines life across multiple levels of organization, from molecules and cells to organisms, populations, and ecosystems. Subdisciplines include molecular biology, physiology, ecology, evolutionary biology, developmental biology, and systematics, among others. Each of these fields applies a range of methods to investigate biological phenomena, including observation, experimentation, and mathematical modeling. Modern biology is grounded i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
