Race (classification of human beings)
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{{Race}}
{{Otheruses|Race}}
The term '''race''' or '''racial group''' usually refers to the concept of dividing [[human]]s into [[population]]s or [[Group (sociology)|group]]s on the basis of various sets of characteristics.<ref name="AAPA">[http://www.physanth.org/positions/race.html AAPA Statement on Biological Aspects of Race] American Association of Physical Anthropologists "Pure races do not exist in the human species today, nor is there any evidence that they have ever existed in the past."</ref> The most widely used human racial [[Taxonomy|categories]] are based on visible [[Trait (biological)|trait]]s (especially [[skin color]], [[cranium|cranial]] or [[face|facial features]] and [[hair|hair texture]]), and self-identification.<ref name="AAPA" /><ref>Bamshad, Michael and Steve E. Olson. [http://schools.tdsb.on.ca/rhking/departments/science/bio/evol_pop_dyn/does_race_exist.pdf "Does Race Exist?"], ''Scientific American Magazine'' ([[10 November]] [[2003]]).</ref>
Conceptions of race, as well as specific ways of [[racial grouping|grouping races]], vary by culture and over time, and are often [[Controversy|controversial]] for scientific as well as [[social identity|social]] and [[identity politics|political]] reasons. The controversy ultimately revolves around whether or not races are natural types or socially constructed, and the degree to which observed differences in ability and achievement, categorized on the basis of race, are a product of inherited (i.e. genetic) traits or environmental, social and cultural factors.
Some argue that although "race" is a valid [[taxonomy|taxonomic]] concept in other species, it cannot be applied to humans.<ref>S O Y Keita, R A Kittles, C D M Royal, G E Bonney, P Furbert-Harris, G M Dunston & C N Rotimi, 2004 "Conceptualizing human variation" in ''Nature Genetics'' 36, S17 - S20 [http://www.nature.com/ng/journal/v36/n11s/full/ng1455.html Conceptualizing human variation]</ref> Many scientists have argued that race definitions are imprecise, arbitrary, derived from [[custom]], have many exceptions, have many gradations, and that the numbers of races delineated vary according to the culture making the racial distinctions; thus they reject the notion that any definition of race pertaining to humans can have taxonomic rigour and validity.<ref>For example this statement expressing the official viewpoint of the American Anthropological Association at [http://www.aaanet.org/stmts/racepp.htm their webpage]: "Evidence from the analysis of genetics (e.g., DNA) indicates that most physical variation lies within so-called racial groups. This means that there is greater variation within 'racial' groups than between them."</ref> Today most scientists study human genotypic and phenotypic variation using concepts such as "population" and "[[Cline (population genetics)|clinal gradation]]". Many contend that while racial categorizations may be marked by phenotypic or genotypic traits, the idea of race itself, and actual divisions of persons into races, are [[social construction|social construct]]s.<ref name="Society in Focus">{{cite book | last = Thompson | first = William | authorlink = | coauthors = Joseph Hickey | year = 2005 | title = Society in Focus | publisher = Pearson | location = Boston, MA| id = 0-205-41365-X}}</ref><ref name="Gordon64" /><ref name="AAAonRace" /><ref name="Palmie07" /><ref name="Mevorach07" /><ref>Daniel A. Segal ''[http://links.jstor.org/sici?sici=0268-540X%28199110%297%3A5%3C7%3A%27EAORP%3E2.0.CO%3B2-7&size=LARGE&origin=JSTOR-enlargePage 'The European': Allegories of Racial Purity]'' Anthropology Today, Vol. 7, No. 5 (Oct., 1991), pp. 7-9 doi:10.2307/3032780</ref><ref>Bindon, Jim. University of Alabama. "[http://www.as.ua.edu/ant/bindon/ant275/presentations/POST_WWII.PDF#search=%22stanley%20marion%20garn%22 Post World War II"]. 2005. August 28, 2006.</ref>
== History ==
{{seealso|Historical definitions of race}}
=== In ancient civilizations ===
{{Seealso|Ancient Egypt and race}}
[[Image:Central Asian Buddhist Monks.jpeg|thumb|150px|Blue-eyed [[Central Asia]]n ([[Tocharian]]?) and East-Asian Buddhist monks, [[Bezeklik]], Eastern [[Tarim Basin]], 9th-10th century.<ref>[http://discovermagazine.com/1994/apr/themummiesofxinj359 The Mummies of Xinjiang], DISCOVER Magazine</ref><ref>[http://www.independent.co.uk/news/world/asia/a-meeting-of-civilisations-the-mystery-of-chinas-celtic-mummies-413638.html A meeting of civilisations: The mystery of China's celtic mummies], The Independent</ref>]]
Given visually complex social relationships, humans presumably have always observed and speculated about the physical differences among individuals and groups. But different societies have attributed markedly different meanings to these distinctions. For example, the [[Ancient Egypt]]ian sacred text called ''[[Book of Gates]]'' identifies four categories that are now conventionally labeled "Egyptians", "Asiatics", "Libyans", and "Nubians", but such distinctions tended to [[conflation|conflate]] differences as defined by physical features such as skin tone, with [[tribe|tribal]] and [[nation]]al identity. [[Classical civilization]]s from [[Ancient Rome|Rome]] to [[Ancient China|China]] tended to invest much more importance in [[family|familial]] or tribal affiliation than with one's physical appearance (Dikötter 1992; Goldenberg 2003). [[Ancient Greek]] and Roman authors also attempted to explain and categorize visible [[biologic]]al differences among peoples known to them. Such categories often also included fantastical human-like beings that were supposed to exist in far-away lands. Some Roman writers adhered to an [[environmental determinism]] in which [[climate]] could affect the appearance and [[character]] of groups (Isaac 2004). In many ancient civilizations, individuals with widely varying physical appearances became full members of a [[society]] by growing up within that society or by adopting that society's [[culture|cultural]] [[norm (sociology)|norms]] (Snowden 1983; Lewis 1990).
[[Julian the Apostate]] was an early observer of the differences in humans, based upon ethnic, cultural, and geographic traits, but as the ideology of "race" had not yet been constructed, he believed that they were the result of "Providence":
<blockquote>Come, tell me why it is that the Celts and the Germans are fierce, while the Hellenes and Romans are, generally speaking, inclined to political life and humane, though at the same time unyielding and warlike? Why the Egyptians are more intelligent and more given to crafts, and the Syrians unwarlike and effeminate, but at the same time intelligent, hot-tempered, vain and quick to learn? For if there is anyone who does not discern a reason for these differences among the nations, but rather declaims that all this so befell spontaneously, how, I ask, can he still believe that the universe is administered by a providence? — Julian, the Apostate.<ref>[http://www.tertullian.org/fathers/julian_apostate_galileans_1_text.htm Julian the Apostate, ''Against the Galileans'']: remains of the 3 books, excerpted from Cyril of Alexandria, ''Contra Julianum'' (1923) pp.319-433</ref>
</blockquote>
[[Medieval]] models of "race" mixed [[Graeco-Roman|Classical]] ideas with the notion that humanity as a whole was descended from [[Shem]], [[Ham]] and [[Japheth]], the three [[sons of Noah]], producing distinct [[Semitic]] ([[Asia]]n), [[Hamitic]] ([[Africa]]n), and [[Japhetic]] ([[Europe]]an) peoples.
===Age of Discovery===
The word "race", along with many of the ideas now associated with the term, were products of [[European imperialism]] and [[colonization]] during the [[age of exploration]]. (Smedley 1999) As Europeans encountered people from different parts of the [[world]], they speculated about the physical, social, and cultural differences among various human groups. The rise of the [[Atlantic slave trade]], which gradually displaced an earlier [[slave trade|trade in slave]]s from throughout the world, created a further [[incentive]] to categorize human groups in order to justify the subordination of African [[slave]]s. (Meltzer 1993) Drawing on Classical sources and upon their own internal interactions — for example, the hostility between the [[English people|English]] and [[Irish people|Irish]] was a powerful influence on early thinking about the differences between people (Takaki 1993) — Europeans began to sort themselves and others into groups associated with physical appearance and with deeply ingrained behaviors and capacities. A set of [[folklore|folk]] [[beliefs]] took hold that linked inherited physical differences between groups to inherited [[intellect]]ual, [[behavioral]], and [[moral]] qualities. (Banton 1977) Although similar ideas can be found in other cultures (Lewis 1990; Dikötter 1992), they appear not to have had as much influence upon their social structures as was found in Europe and the parts of the world colonized by Europeans. However, often brutal conflicts between ethnic groups have existed throughout history and across the world.
=== Scientific concepts ===
{{further|[[Race (historical definitions)]], [[Scientific racism]], [[Craniofacial anthropometry]]}}
The first scientific attempts to classify humans by categories of race date from the 17th century, along with the development of European imperialism and colonization around the world. The first post-[[Graeco-Roman|Classical]] published classification of humans into distinct races seems to be [[François Bernier]]'s ''Nouvelle division de la terre par les différents espèces ou races qui l'habitent'' ("New division of Earth by the different species or races which inhabit it"), published in 1684.
=== 17th and 18th century ===
According to philosopher [[Michel Foucault]], theories of both racial and class conflict can be traced to 17th century political debates about innate differences among ethnicities. In England radicals such as [[John Lilburne]] emphasised conflicts between [[Anglo-Saxons|Saxon]] and [[Normans|Norman]] peoples. In France [[Henri de Boulainvilliers]] argued that the Germanic [[Franks]] possessed a natural right to leadership, in contrast to descendants of the [[Gauls]]. In the 18th century, the differences among human groups became a focus of scientific investigation (Todorov 1993). Initially, scholars focused on cataloguing and describing "[[The Natural Varieties of Mankind]]," as [[Johann Friedrich Blumenbach]] entitled his 1775 text (which established the five major divisions of humans still reflected in some racial classifications, i.e., the [[Caucasoid race]], [[Mongoloid race]], [[Africoid race|Ethiopian race]] (later termed the [[Negroid]] race), [[Indigenous peoples of the Americas|American Indian race]], and [[Malayan race]]). From the 17th through the 19th centuries, the merging of folk beliefs about group differences with scientific explanations of those differences produced what one scholar has called an "[[ideology]] of race" (Smedley 1999). According to this ideology, races are primordial, natural, enduring and distinct. It was further argued that some groups may be the result of mixture between formerly distinct populations, but that careful study could distinguish the ancestral races that had combined to produce admixed groups.
=== 19th century ===
The 19th century saw attempts to change race from a taxonomic to a biological concept. In the 19th century a number of [[natural science|natural scientists]] wrote on race: [[Georges Cuvier]], [[Charles Darwin]], [[Alfred Wallace]], [[Francis Galton]], [[James Cowles Pritchard]], [[Louis Agassiz]], [[Charles Pickering NMI|Charles Pickering]], and [[Johann Friedrich Blumenbach]]. As the science of [[anthropology]] took shape in the 19th century, European and American scientists increasingly sought explanations for the behavioral and cultural differences they attributed to groups (Stanton 1960). For example, using [[anthropometrics]], invented by Francis Galton and [[Alphonse Bertillon]], they measured the shapes and sizes of skulls and related the results to group differences in intelligence or other attributes (Lieberman 2001).
These scientists made three claims about race: first, that races are objective, naturally occurring divisions of humanity; second, that there is a strong relationship between biological races and other human phenomena (such as [[forms of activity and interpersonal relations]] and culture, and by extension the relative [[materialism|material success]] of cultures), thus biologizing the notion of "race", as Foucault demonstrated in his historical analysis; third, that race is therefore a valid scientific category that can be used to explain and predict individual and group behavior. Races were distinguished by [[human skin color|skin color]], [[facial type]], [[cranium|cranial]] profile and size, texture and color of hair. Moreover, races were almost universally considered to reflect group differences in moral character and [[intelligence (trait)|intelligence]].
The [[eugenics]] movement of the late 19th and early 20th centuries, inspired by [[Arthur Gobineau]]'s ''[[An Essay on the Inequality of the Human Races]]'' (1853–1855) and [[Vacher de Lapouge]]'s "anthroposociology", asserted as self-evident the biological inferiority of particular groups (Kevles 1985). In many parts of the world, the idea of race became a way of rigidly dividing groups by culture as well as by physical appearances (Hannaford 1996). Campaigns of oppression and [[genocide]] were often motivated by supposed racial differences (Horowitz 2001).
In [[Charles Darwin]]'s most controversial book, ''[[The Descent of Man]]'', he made strong suggestions of racial differences and European superiority. In Darwin's view, stronger tribes of humans always replaced weaker tribes. As savage tribes came in conflict with civilized nations, such as England, the less advanced people were destroyed.<ref>Charles Darwin, [http://www.literature.org/authors/darwin-charles/the-descent-of-man/chapter-07.html ''The Descent of Man'', Chapter 7 - On the Races of Man.] Consider, for instance, the following excerpt: "We thus see that many of the wilder races of man are apt to suffer much in health when subjected to changed conditions or habits of life, and not exclusively from being transported to a new climate. Mere alterations in habits, which do not appear injurious in themselves, seem to have this same effect; and in several cases the children are particularly liable to suffer. It has often been said, as Mr. Macnamara remarks, that man can resist with impunity the greatest diversities of climate and other changes; but this is true only of the civilised races."</ref> Nevertheless, he also noted the great difficulty naturalists had in trying to decide how many "races" there actually were (Darwin was himself a [[monogenesis|monogenist]] on the question of race, believing that all humans were of the same species and finding "race" to be a somewhat arbitrary distinction among some groups):
<blockquote>Man has been studied more carefully than any other animal, and yet there is the greatest possible diversity amongst capable judges whether he should be classed as a single species or race, or as two (Virey), as three (Jacquinot), as four (Kant), five (Blumenbach), six (Buffon), seven (Hunter), eight (Agassiz), eleven (Pickering), fifteen (Bory St. Vincent), sixteen (Desmoulins), twenty-two (Morton), sixty (Crawfurd), or as sixty-three, according to Burke. This diversity of judgment does not prove that the races ought not to be ranked as species, but it shews that they graduate into each other, and that it is hardly possible to discover clear distinctive characters between them.<ref>Darwin, C. (1871/1874). The Descent of Man, 2nd. Ed., London: John Murray.</ref>
</blockquote>
== Modern debates ==
=== Models of human evolution ===
In a recent article, Leonard Lieberman and Fatimah Jackson have suggested that any new support for a biological concept of race will likely come from another source, namely, the study of human evolution. They therefore ask what, if any, implications current models of human evolution may have for any biological conception of race.<ref>Leonard Lieberman and Fatimah Linda C. Jackson (1995) "Race and Three Models of Human Origin" in ''American Anthropologist'' Vol. 97, No. 2, pp. 232-234</ref>
Today, all [[humans]] are classified as belonging to the species ''Homo sapiens'' and sub-species ''Homo sapiens sapiens.'' However, this is not the first species of hominids: the first species of genus ''Homo'', [[Homo habilis]], evolved in East Africa at least 2 million years ago, and members of this species populated different parts of Africa in a relatively short time. ''[[Homo erectus]]'' evolved more than 1.8 million years ago, and by 1.5 million years ago had spread throughout the Old World. Virtually all physical anthropologists agree that ''Homo sapiens'' evolved out of ''Homo erectus.'' Anthropologists have been divided as to whether ''Homo sapiens'' evolved as one interconnected species from ''H. erectus'' (called the Multiregional Model, or the Regional Continuity Model), or evolved only in East Africa, and then migrated out of Africa and replaced ''H. erectus'' populations throughout the Old World (called the Out of Africa Model or the Complete Replacement Model). Anthropologists continue to debate both possibilities, and the evidence is technically ambiguous as to which model is correct, although most anthropologists currently favor the Out of Africa model.
==== Multiregional model====
{{main|Multiregional hypothesis}}
Advocates of the Multiregional model, primarily [[Milford Wolpoff]] and his associates, have argued that the simultaneous evolution of ''H. sapiens'' in different parts of Europe and Asia would have been possible if there were a degree of [[gene flow]] between archaic populations.<ref>Thorne, Alan, and Milford Wolpoff (1992) "The Multiregional Evolution of humans" in ''Scientific American, April 76-93; Smith, Fred and Frank Spencer, eds (1984) ''The Origin of Modern Humans''</ref> Similarities of morphological features between archaic European and Chinese populations and modern ''H. sapiens'' from the same regions, Wolpoff argues, support a regional continuity only possible within the Multiregional model.<ref>Robert H. Lavenda and Emily A. Shultz ''Anthropology, what does it mean to be human?'' Oxford (New York:2008) 132.</ref> Wolpoff and others further argue that this model is consistent with [[Cline (population genetics)|clinal patterns]] of phenotypic variation (Wolpoff 1993). Lieberman and Jackson have related this theory to race with the following statement:
{{cquote|The major implication for race in the multiregional evolution continuity model involves the time depth of a million or more years in which race differentiation might evolve in diverse ecological regions [...]. This must be balanced against the degree of gene flow and the transregional operation of natural selection on encephalization due to development of tools and, more broadly, culture.<ref>Leonard Lieberman and Fatimah Linda C. Jackson (1995) "Race and Three Models of Human Origin" in ''American Anthropologist'' Vol. 97, No. 2, pp. 237</ref>}}
====Out of Africa model====
{{seealso|Recent single origin hypothesis}}
According to the Out of Africa Model, developed by [[Christopher Stringer]] and Peter Andrews, modern ''Homo sapiens'' evolved in Africa 200,000 years ago. ''H. sapiens'' began migrating from Africa around 50,000 years ago and eventually replaced existing [[hominid]] species in Europe and Asia.<ref>[http://news.nationalgeographic.com/news/2007/07/070718-african-origin.html Modern Humans Came Out of Africa, "Definitive" Study Says]</ref><ref>Christopher Stringer and Peter Andrews (1988) "Genetic and Fossil Evidence for the Origin of Modern Humans" in ''Science'' 239: 1263-1268</ref> This model has gained support by recent research using [[mitochondrial DNA]] (mtDNA). After analysing genealogy trees constructed using 133 types of mtDNA, they concluded that all were descended from a woman from Africa, dubbed [[Mitochondrial Eve]].<ref>Rebecca L. Cann, Mark Stoneking, Allan C. Wilson (1987) "Mitochondrial DNA and human evolution" in ''Nature'' 325: 31-36)</ref> Lieberman and Jackson have related this theory to race with the following comment:
{{cquote|There are three major implications of this model for the race concept. First, the shallow time dimension minimizes the degree to which racial differences could have evolved [...]. Second, the mitochondrial DNA model presents a view that is very much different from Carleton Coon's (1962) concerning the time at which Africans passed the threshold from archaic to modern, thereby minimizing race differences and avoiding racist implications. However, the model, as interpreted by Wainscoat et al. (1989:34), does describe "a major division of human populations into an African and a Eurasian group." This conclusion could best be used to emphasize the degree of biological differences, and thereby provide support for the race concept. Third, the replacement of preexisting members of genus Homo (with little gene flow) implies several possible causes from disease epidemics to extermination. If the latter, then from a contemporary viewpoint, xenophobia or racism may have been practiced"<ref>Leonard Lieberman and Fatimah Linda C. Jackson (1995) "Race and Three Models of Human Origin" in ''American Anthropologist'' Vol. 97, No. 2, pp. 235–236</ref>}}
==== Comparison of the two models ====
Lieberman and Jackson have argued that while advocates of both the Multiregional Model and the Out of Africa Model use the word race and make racial assumptions, none define the term.<ref>Leonard Lieberman and Fatimah Linda C. Jackson (1995) "Race and Three Models of Human Origin" in ''American Anthropologist'' Vol. 97, No. 2, pp. 237</ref> They conclude that
"Each model has implications that both magnify and minimize the differences between races. Yet each model seems to take race and races as a conceptual reality. The net result is that those anthropologists who prefer to view races as a reality are encouraged to do so" and conclude that students of human evolution would be better off avoiding the word race, and instead describe genetic differences in terms of populations and clinal gradations.<ref>Leonard Lieberman and Fatimah Linda C. Jackson (1995) "Race and Three Models of Human Origin" in ''American Anthropologist'' Vol. 97, No. 2, pp. 239</ref>
=== Race as subspecies ===
{{further|[[Race (biology)]] and [[Subspecies]].}}
With the advent of the [[modern synthesis]] in the early 20th century, many biologists sought to use evolutionary models and populations genetics in an attempt to formalise taxonomy below the species level. The term subspecies is used by biologists when a group of organisms are classified in such a way. In biology the term "race" is very rarely used because it is ambiguous, "'Race' is not being defined or used consistently; its referents are varied and shift depending on context. The term is often used colloquially to refer to a range of human groupings. Religious, cultural, social, national, ethnic, linguistic, genetic, geographical and anatomical groups have been and sometimes still are called 'races'".<ref name="Keita"/> Generally when it is used it is synonymous with subspecies.<ref name="Templeton">Templeton, 1998</ref><ref name="Keita">Keita ''et al.'' 2004</ref><ref>Long and Kittles, 2003</ref> One of the main obstacles to identifying subspecies is that, while it is a recognised taxonomic term, it has no precise definition.<ref name="Templeton"/>
Some species of organisms do not appear to fragment into subgroups, while others do seem to form such subspecific groups. A monotypic species comprises a single group or rather a single subspecies. Monotypic species can occur in several ways:
* All members of the species are very similar and cannot be sensibly divided into biologically significant subcategories.
* The individuals vary considerably but the variation is essentially random and largely meaningless so far as genetic transmission of these variations is concerned (many plant species fit into this category, which is why horticulturists interested in preserving, say, a particular flower color avoid propagation from seed, and instead use vegetative methods like propagation from cuttings).
* The variation among individuals is noticeable and follows a pattern, but there are no clear dividing lines among separate groups: they fade imperceptibly into one another. Such clinal variation always indicates substantial [[gene flow]] among the apparently separate groups that make up the population(s). Populations that have a steady, substantial gene flow among them are likely to represent a monotypic species even when a fair degree of genetic variation is obvious.
A ''polytypic'' species has two or more subspecies. These are separate populations that are more genetically different from one another and that are more reproductively isolated, gene flow between these populations is much reduced leading to genetic differentiation.
====Morphological subspecies====
Traditionally subspecies are seen as geographically isolated and genetically differentiated populations.<ref name="Templeton"/> Or to put it another way "the designation 'subspecies' is used to indicate an objective degree of microevolutionary divergence"<ref name="Keita"/> One objection to this idea is that it does not identify any degree of differentiation, therefore any population that is somewhat biologically different could be considered a subspecies, even to the level of a local population. As a result it is necessary to impose a threshold on the level of difference that is required for a population to be designated a subspecies.<ref name="Templeton"/> This effectively means that populations of organisms must have reached a certain measurable level of difference in order to be recognised as subspecies.
[[Dean Amadon]] proposed in 1949 that subspecies would be defined according to the seventy-five percent rule which means that 75% of a population must lie outside 99% of the range of other populations for a given defining [[morphology (biology)|morphological]] character or a set of characters. The 75 percent rule still has defenders but other scholars argue that it should be replaced with 90 or 95 percent rule.<ref>AMADON, D. 1949. The seventy-five percent rule for subspecies. Condor 51:250-258.</ref><ref>MAYR, E. 1969. Principles of Systematic Zoology. McGraw-Hill, New York.</ref><ref>Patten MA & Unitt P. (2002). Diagnosability versus mean differences of sage sparrow subspecies. Auk. vol 119, no 1. p. 26-35.</ref>
When biologists study non-human populations, the standard threshold at which [[morphology (biology)|morphological]] diversity between two different populations is considered differentiated enough to be classified as subspecies is set at 70-75%. Smith et al. write:
<blockquote>The non-discrete nature of subspecies is evident from their definition as geographic segments of any given gonochoristic (bisexually reproducing) species differing from each other to a reasonably practical degree (e.g., at least 70-75%), but to less than totality. All subspecies are allopatric (either dichopatric [with non-contiguous ranges] or parapatric [with contiguous ranges], except for cases of circular overlap with sympatry); sympatry is conclusive evidence (except for cases of circular overlap) of allospecificity (separate specific status). Parapatric subspecies interbreed and exhibit intergradation in contact zones, but such taxa maintain the required level of distinction in one or more characters outside of those zones. Dichopatric populations are regarded as subspecies if they fail to exhibit full differentiation (i.e., exhibit overlap in variation of their differentiae up to 25-30%), even in the absence of contact (overlap exceeding 25-30% does not qualify for taxonomic recognition of either dichopatric populations or of parapatric populations outside of their zones of intergradation). Phenotypic adjustment to differing environmental conditions through natural selection is likely the primary factor in divergence of parapatric subspecies, and undoubtedly is involved in some dichopaffic subspecies. The founder effect and genetic drift are involved more in the latter than in the former.</blockquote>
Thus, according to the ''seventy-five percent rule'' two populations represent different subspecies if the morphological differences between them reach between 25-30%.
In 1978, [[Sewall Wright]] suggested that human populations that have long inhabited separated parts of the world should, in general, be considered to be of different subspecies by the usual criterion that most individuals of such populations can be allocated correctly by inspection. It does not require a trained anthropologist to classify an array of Englishmen, West Africans, and Chinese with 100% accuracy by features, skin color, and type of hair in spite of so much variability within each of these groups that every individual can easily be distinguished from every other. However, it is customary to use the term race rather than subspecies for the major subdivisions of the human species as well as for minor ones.<ref>Wright, S. 1978. Evolution and the Genetics of Populations, Vol. 4, Variability Within and Among Natural Populations. Univ. Chicago Press, Chicago, Illinois. p. 438</ref>
Humans can be correctly assigned to races at much greater than 75% accuracy on the basis of morphological traits while [[chimpanzee]] subspecies are morphologically indistinct, and difficult or impossible to classify when raised in captivity.<ref>Stone, A.C., R. Griffiths, S. Zegura, M. Hammer. 2002. High levels of Y chromosome nucleotide diversity in the genus Pan. Proceedings of the National Academy of Sciences 99:43-48.</ref><ref>66. Kaessmann, H., Wiebe, V., Paabo, S. 1999. Extensive Nuclear DNA Sequence Diversity Among Chimpanzees. Science 286:1159-1162.</ref><ref>Wright. 1978. p. 439</ref>
On the other hand in practice subspecies are often defined by easily observable physical appearance, but there is not necessarily any evolutionary significance to these observed differences, so this form of classification is generally not accepted by evolutionary biologists.<ref name="Templeton"/><ref name="Keita"/>
Because of the difficulty in classifying subspecies morphologically, many biologists began to reject the concept altogether, citing problems such as:<ref name="Keita"/>
*Visible physical differences do not correlate with one another, leading to the possibility of different classifications for the same individual organisms.<ref name="Keita"/>
*Parallel evolution can lead to the existence of the appearance of similarities between groups of organisms that are not part of the same species.<ref name="Keita"/>
*The existence of isolated populations within previously designated subspecies.<ref name="Keita"/>
*That the criteria for classification are arbitrary.<ref name="Keita"/>
====Subspecies as isolated differentiated populations====
Genetic differences between populations of organisms can be determined using the [[fixation index]] of [[Sewall Wright]], which is often abbreviated to F<sub>ST</sub>. This statistic is used to compare differences between any two given populations. For example it is often stated that the fixation index for humans is about 0.15. This means that about 85% of the variation measured in the human population is within any population, and about 15% of the variation occurs between populations.<ref name="Templeton"/><ref name="Keita"/>
Citing Smith, Templeton asserts that an F<sub>ST</sub> value of 0.25 or 0.30 between populations is a “standard criterion” for subspecies classification. However, Smith doesn't mention the concept of F<sub>ST</sub> in his paper, he is discussing variation in morphology and discusses the 75% rule. Templeton reported that the [[white-tailed deer]] has an F<sub>ST</sub> of about 60% and the [[grey wolf]] has an F<sub>ST</sub> approaching 90% for mtDNA. The F<sub>ST</sub> of grey wolves is 0.168 in autosomal loci, however.<ref>Wayne, R.K., Lehmann, N., Allard, M.W., Honeycutt, R.L. 1992. Mitochondrial DNA Variability of the Gray Wolf: Genetic Consequences of Population Decline and Habitat Fragmentation. Conservation Biology 6:559-569.</ref><ref>82. Roy, M.S., Gefen, E., Smith, D., Ostrander, E.A., Wayne, R.K. 1994. Patterns of Differentiation and Hybridization in North American Wolflike Canids, Revealed by Analysis of Microsatellite Loci. Molecular Biology and Evolution 11:553-570.</ref> On the other hand, in a paper reporting on the [[Phylogenetics|phylogenetic]] structure of the Leopard ''[[Panthera pardus]]'' species of Africa and Asia, Uphyrkina ''et al.'' found that 76.04% of mtDNA variation was distributed between leopard populations and 23.96% within populations, for [[microsatellite]] autosomal data, 0.358 (35.8%) of the variation was found between populations.<ref name="Uphyrkina">Olga Uphyrkina, Warren E. Johnson, Howard Quigley, Dale Miquelle, Laurie Marker, Mitchel Bush, Stephen J. O'Brien (2001) ''Phylogenetics, genome diversity and origin of modern leopard, ''Panthera pardus'''' ''Molecular Ecology'' '''10''' (11), 2617–2633. {{doi|10.1046/j.0962-1083.2001.01350.x}}</ref> This compares to an mtDNA F<sub>ST</sub> of between 0.24-0.27 (24-27%), and a genomic F<sub>ST</sub> of about 0.15 (15%) for humans,<ref name="tishkoff>Sarah A Tishkoff and Kenneth K Kidd (2004) ''Implications of biogeography of human populations for 'race' and medicine'' ''Nature Genetics'' '''36''', S21 - S27 (2004) {{doi|10.1038/ng1438}}</ref> and an F<sub>ST</sub> of 0.09-0.32 for autosomal microsatellite DNA between three Chimpanzee (''Pan troglodytes'') populations and of 0.51-0.68 between these three populations and the bonobo (''Pan paniscus'') populations.<ref name="chimp">Celine Becquet, Nick Patterson, Anne C Stone, Molly Przeworski, and David Reich (2007) ''Genetic Structure of Chimpanzee Populations. PLoS Genet.'' '''3'''(4): e66.{{doi|10.1371/journal.pgen.0030066}}.</ref> The following guidelines were suggested by [[Sewall Wright]] for interpreting F<sub>ST</sub>:
<blockquote>
“The range 0 to 0.05 may be considered as indicating little genetic differentiation.
The range 0.05 to 0.15 indicates moderate genetic differentiation.
The range 0.15 to 0.25 indicates great genetic differentiation.
Values of FST above 0.25 indicate very great genetic differentiation.” </blockquote>
Wright found differences in F<sub>ST</sub> for various species from 0.023-0.501.<ref name="graves">Joseph L. Graves, (2006) ''[http://raceandgenomics.ssrc.org/Graves/ What We Know and What We Don’t Know: Human Genetic Variation and the Social Construction of Race]'' from ''[http://raceandgenomics.ssrc.org/ Race and Genomics]''</ref> For humans the F<sub>ST</sub> is usually given as 0.15, of this 15% that is distributed between populations about 3-6% is distributed between geographically close populations occupying the same continent and about 6-10% is distributed between more distant continental groups, these figures vary somewhat depending on the type of genetic systems used, but the general observation has been reproduced in numerous studies.<ref name="Lewontin">Lewontin, 2006</ref> This indicates that some of the between population variation for humans is found within any "race" and about 6-10% of variation is found between "races", giving an F<sub>ST</sub> of 0.06-0.1 for human "races".<ref name="duster"/>
It has also been noted that:
*"First, compared with many other mammalian species, humans are genetically less diverse... For example, the chimpanzee subspecies living just in central and western Africa have higher levels of diversity than do humans (Ebersberger et al. 2002; Yu et al. 2003; Fischer et al. 2004)." Human variation is also distributed in an unusual and not easily understood fashion compared to other mammalian species: "The details of this distribution are impossible to describe succinctly because of the difficulty of defining a 'population,' the clinal nature of variation, and heterogeneity across the genome (Long and Kittles 2003).... This distribution of genetic variation differs from the pattern seen in many other mammalian species, for which existing data suggest greater differentiation between groups (Templeton 1998; Kittles and Weiss 2003)."<ref name="REGWG">''[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1275602 The Use of Racial, Ethnic, and Ancestral Categories in Human Genetics Research]'' by Race, Ethnicity, and Genetics Working Group. ''Am J Hum Genet.'' 2005 '''77'''(4): 519–532.</ref>
*"Since the 1980s, there have been indications that the genetic diversity of humans is low compared with that of many other species. This has been interpreted to mean that humans are a relatively young species, so populations have had relatively little time to differentiate from one another. For example, 2 randomly chosen humans differ at ~1 in 1,000 nucleotide pairs, whereas two chimpanzees differ at ~1 in 500 nucleotide pairs.<ref>''[http://www.fiu.edu/~biology/pcb5665/RACEgen.pdf DECONSTRUCTING THE RELATIONSHIP BETWEEN GENETICS AND RACE]'' Michael Bamshad, Stephen Wooding, Benjamin A. Salisbury and J. Claiborne Stephens. ''Nature Genetics'' (2004) '''5''':598-609</ref>
*"'Race' is a legitimate taxonomic concept that works for chimpanzees but does not apply to humans (at this time). The nonexistence of 'races' or subspecies in modern humans does not preclude substantial genetic variation that may be localized to regions or populations....The DNA of an unknown individual from one of the sampled populations would probably be correctly linked to a population. Because this identification is possible does not mean that there is a level of differentiation equal to 'races'. The genetics of ''Homo sapiens'' shows gradients of differentiation."<ref>[http://www.nature.com/ng/journal/v36/n11s/full/ng1455.html Conceptualizing human variation]'' by S O Y Keita, 2, R A Kittles1, C D M Royal, G E Bonney, P Furbert-Harris, G M Dunston & C N Rotimi. ''Nature Genetics'' '''36''', S17 - S20 (2004)</ref>
*"Humans are ~98.8% similar to chimpanzees at the nucleotide level and are considerably more similar to each other, differing on average at only 1 of every 500−1,000 nucleotides between chromosomes. This degree of diversity is less than what typically exists among chimpanzees.<ref>''[http://www.nature.com/ng/journal/v36/n11s/full/ng1438.html Implications of biogeography of human populations for 'race' and medicine]'' by Sarah A Tishkoff & Kenneth K Kidd. ''Nature Genetics'' '''36''', S21 - S27 (2004)</ref>
*"The average proportion of nucleotide differences between a randomly chosen pair of humans (i.e., average nucleotide diversity, or π) is consistently estimated to lie between 1 in 1,000 and 1 in 1,500. This proportion is low compared with those of many other species, from fruit flies to chimpanzees...."<ref>''[http://www.nature.com/ng/journal/v36/n11s/full/ng1435.html Genetic variation, classification and 'race']'' by Lynn B Jorde & Stephen P Wooding. ''Nature Genetics' '''36''', S28 - S33 (2004)</ref>
=== Population genetics: population and cline ===
At the beginning of the 20th century, anthropologists questioned, and eventually abandoned, the claim that biologically distinct races are isomorphic with distinct linguistic, cultural, and social groups. Shortly thereafter, the rise of [[population genetics]] provided scientists with a new understanding of the sources of phenotypic variation. This new science has led many mainstream evolutionary scientists in [[anthropology]] and [[biology]] to question the very validity of race as a scientific concept describing an objectively real phenomenon. Those who came to reject the validity of the concept of race did so for four reasons: empirical, definitional, the availability of alternative concepts, and ethical (Lieberman and Byrne 1993).
The first to challenge the concept of race on empirical grounds were [[anthropology|anthropologists]] [[Franz Boas]], who demonstrated phenotypic plasticity due to environmental factors (Boas 1912), and [[Ashley Montagu]] (1941, 1942), who relied on evidence from genetics. [[Zoology|Zoologists]] Edward O. Wilson and W. Brown then challenged the concept from the perspective of general animal systematics, and further rejected the claim that "races" were equivalent to "subspecies" (Wilson and Brown 1953).
====Clines====
One of the crucial innovations in reconceptualizing genotypic and phenotypic variation was anthropologist C. Loring Brace's observation that such variations, insofar as it is affected by [[natural selection]], migration, or [[genetic drift]], are distributed along geographic gradations or [[wiktionary:cline|clines]] (Brace 1964). This point called attention to a problem common to phenotype-based descriptions of races (for example, those based on hair texture and skin color): they ignore a host of other similarities and differences (for example, blood type) that do not correlate highly with the markers for race. Thus, anthropologist Frank Livingstone's conclusion that, since clines cross racial boundaries, "there are no races, only clines" (Livingstone 1962: 279).
In a response to Livingston, [[Theodore Dobzhansky]] argued that when talking about "race" one must be attentive to how the term is being used: "I agree with Dr. Livingston that if races have to be 'discrete units,' then there are no races, and if 'race' is used as an 'explanation' of the human variability, rather than vice versa, then the explanation is invalid." He further argued that one could use the term race if one distinguished between "race differences" and "the race concept." The former refers to any distinction in gene frequencies between populations; the latter is "a matter of judgment." He further observed that even when there is clinal variation, "Race differences are objectively ascertainable biological phenomena .... but it does not follow that racially distinct populations must be given racial (or subspecific) labels."<ref>Theodosious Dobzhansky "Comment" in ''Current Anthropology'' 3(3): 279-280</ref> In short, Livingston and Dobzhansky agree that there are genetic differences among human beings; they also agree that the use of the race concept to classify people, and how the race concept is used, is a matter of social convention. They differ on whether the race concept remains a meaningful and useful social convention.
In 1964, biologists Paul Ehrlich and Holm pointed out cases where two or more clines are distributed discordantly—for example, melanin is distributed in a decreasing pattern from the equator north and south; frequencies for the haplotype for beta-S hemoglobin, on the other hand, radiate out of specific geographical points in Africa (Ehrlich and Holm 1964). As anthropologists Leonard Lieberman and Fatimah Linda Jackson observe, "Discordant patterns of heterogeneity falsify any description of a population as if it were genotypically or even phenotypically homogeneous" (Lieverman and Jackson 1995).
Patterns such as those seen in human physical and genetic variation as described above, have led to the consequence that the number and geographic location of any described races is highly dependent on the importance attributed to, and quantity of, the traits considered. For example if only skin colour and a "two race" system of classification were used, then one might classify [[Indigenous Australians]] in the same "race" as [[Black people]], and [[Caucasian race|Caucasians]] in the same "race" as [[East Asian]] people, but biologists and anthropologists would dispute that these classifications have any scientific validity. On the other hand the greater the number of traits (or [[allele]]s) considered, the more subdivisions of humanity are detected, due to the fact that traits and gene frequencies do not always correspond to the same geographical location, or as Ossario and Duster (2005) put it:{{quotation|Anthropologists long ago discovered that humans' physical traits vary gradually, with groups that are close geographic neighbors being more similar than groups that are geographically separated. This pattern of variation, known as clinal variation, is also observed for many alleles that vary from one human group to another. Another observation is that traits or alleles that vary from one group to another do not vary at the same rate. This pattern is referred to as nonconcordant variation. Because the variation of physical traits is clinal and nonconcordant, anthropologists of the late 19th and early 20th centuries discovered that the more traits and the more human groups they measured, the fewer discrete differences they observed among races and the more categories they had to create to classify human beings. The number of races observed expanded to the 30s and 50s, and eventually anthropologists concluded that there were no discrete races (Marks, 2002). Twentieth and 21st century biomedical researchers have discovered this same feature when evaluating human variation at the level of alleles and allele frequencies. Nature has not created four or five distinct, nonoverlapping genetic groups of people.<ref name="duster">Pilar Ossorio and Troy Duster (2006) ''Race and Genetics Controversies in Biomedical, Behavioral, and Forensic Sciences'' ''American Psychologist'' '''60''' 115–128 {{doi|10.1037/0003-066X.60.1.115}}</ref>}}
====Populations====
Population geneticists have debated as to whether the concept of population can provide a basis for a new conception of race. In order to do this a working definition of population must be found. Surprisingly there is no generally accepted concept of population that biologists use. It has been pointed out that the concept of population is central to ecology, evolutionary biology and conservation biology, but also that most definitions of population rely on qualitative descriptions such as "a group of organisms of the same species occupying a particular space at a particular time"<ref name="waples">''What is a population? An empirical evaluation of some genetic methods for identifying the number of gene pools and their degree of connectivity.'' by ROBIN S. WAPLES and OSCAR GAGGIOTTI. ''Molecular Ecology'' (2006) '''15''', 1419–1439. {{doi|10.1111/j.1365-294X.2006.02890.x}}</ref> Waples and Gaggiotti identify two broad types of definitions for populations, those that fall into an ''ecological paradigm'' and those that fall into an ''evolutionary paradigm''. Examples such definitions are:
*''Ecological paradigm'': A group of individuals of the same species that co-occur in space and time and have an opportunity to interact with each other.
*''Evolutionary paradigm'': A group of individuals of the same species living in close enough proximity that any member of the group can potentially mate with any other member.<ref name="waples"/>
[[Richard Lewontin]], claiming that 85 percent of human variation occurs within populations, and not among populations, argued that neither "race" nor "subspecies" were appropriate or useful ways to describe populations (Lewontin 1973). Nevertheless, barriers—which may be cultural or physical— between populations can limit gene flow and increase genetic differences. Recent work by population geneticists conducting research in Europe suggests that ethnic identity can be a barrier to gene flow.<ref>Koertvelyessy, TA and MT Nettleship 1996 Ethnicity and mating structure in Southwestern Hungary. Rivista di Antropologia (Roma) 74:45-53</ref><ref>Koertvelyessy, T 1995 Etnicity, isonymic relationships, and biological distance in Northeastern Hungary. Homo 46/1:1-9.</ref><ref>Pettener. D 1990 Temporal trends in marital structure and isonymy in S. Paolo Albanese, Italy. Human Biology 6:837-851.</ref><ref>Biondi, G, P Raspe, GW Lasker, and GGN Mascie-Taylor 1990 Relationships estimated by isonymy among the Italo-Greco villages of southern Italy. Human Biology 62:649-663.</ref> Others, such as [[Ernst Mayr]], have argued for a notion of "geographic race" [http://www.goodrumj.com/Mayr.html]. Some researchers report the variation between racial groups (measured by [[Sewall Wright|Sewall Wright's]] population structure statistic F<sub>ST</sub>) accounts for as little as 5% of human genetic variation². [[Sewall Wright]] himself commented that if differences this large were seen in another species, they would be called subspecies.<ref>Wright S. 1978. Evolution and the Genetics of Populations, Vol. 4, Variability Within and Among Natural Populations. Chicago, II: Univ. Chicago Press</ref> In 2003 [[A. W. F. Edwards]] argued that cluster analysis supersedes Lewontin's arguments (see below).
These empirical challenges to the concept of race forced evolutionary sciences to reconsider their definition of race. Mid-century, anthropologist William Boyd defined race as:
:A population which differs significantly from other populations in regard to the frequency of one or more of the genes it possesses. It is an arbitrary matter which, and how many, gene loci we choose to consider as a significant "constellation" (Boyd 1950).
Lieberman and Jackson (1994) have pointed out that "the weakness of this statement is that if one gene can distinguish races then the number of races is as numerous as the number of human couples reproducing." Moreover, anthropologist Stephen Molnar has suggested that the discordance of clines inevitably results in a multiplication of races that renders the concept itself useless (Molnar 1992).
<!-- [[Image:Map of skin hue equi3.png|right|thumb|500px|[[Human skin color]] map. Data for native populations collected by R. Biasutti prior to 1940]] ***This map is discredited, plus it's ugly. I can make a better looking map, if I had the correct data [[User:Jeeny]] ***-->
The distribution of many physical traits resembles the distribution of genetic variation within and between human populations (American Association of Physical Anthropologists 1996; Keita and Kittles 1997). For example, ~90% of the variation in human head shapes occurs within every human group, and ~10% separates groups, with a greater variability of head shape among individuals with recent African ancestors (Relethford 2002).
=== Molecular genetics: lineages and clusters ===
With the recent availability of large amounts of human genetic data from many geographically distant human groups scientists have again started to investigate the relationships between people from various parts of the world. One method is to investigate DNA molecules that are passed down from mother to child (mtDNA) or from father to son (Y chromosomes), these form molecular lineages and can be informative regarding prehistoric population migrations. Alternatively autosomal alleles are investigated in an attempt to understand how much genetic material groups of people share. This work has led to a debate amongst geneticists, molecular anthropologists and medical doctors as to the validity of conceps such as "race". Some researchers insist that classifying people into groups based on ancestry may be important from medical and social policy points of view, and claim to be able to do so accurately. Others claim that individuals from different groups share far too much of their genetic material for group membership to have any medical implications. This has reignited the scientific debate over the validity of human classification and concepts of "race".
====Molecular lineages, Y chromosomes and mitochondrial DNA====
[[Mitochondria]] are small [[organelle]]s that lie in the [[cytoplasm]] of [[Eukaryote|eucaryotic cells]], such as those of humans. Their primary purpose is to provide energy to the cell. Mitochondria are thought to be the vestigial remains of [[symbiote|symbiotic]] [[bacteria]] that were once free living. One indication that mitochondria were once free living is that they contain a relatively small circular segment of [[DNA]], called [[mitochondrial DNA]] (mtDNA). The overwhelming majority of a human's DNA is contained in [[chromosome]]s in the [[Cell nucleus|nucleus]] of the cell, but mtDNA is an exception. An individual inherits their cytoplasm and the organelles it contains exclusively from their mother, as these are derived from the [[ovum]] (egg cell), [[sperm]] only carry chromosomal DNA due to the necessity of maintaining [[motility]]. When a [[mutation]] arises in mtDNA molecule the mutation is therefore passed in a direct female line of descent. These mutations are derived from copying mistakes, when the DNA is copied it is possible that a single mistake occurs in the [[DNA sequence]], these single mistakes are called [[single nucleotide polymorphism]]s (SNPs).
Human [[Y chromosome]]s are male specific [[XY sex-determination system|sex chromosomes]], any human that possesses a Y chromosome will be [[Morphology (biology)|morphologically]] male. Y chromosomes are therefore passed from father to son, although Y chromosomes are situated in the cell nucleus, they only [[Genetic recombination|recombine]] with the X chromosome at the [[Y chromosome#Recombination inhibition|ends of the Y chromosome]], the vast majority of the Y chromosome (95%) does not recombine. Therefore, as with mtDNA, when mutations (SNPs) arise in the Y chromosome they are passed on directly from father to son in a direct male line of descent.
[[Image:Molecular lineage.png|thumb|300px|right|{{legend|#959595|Ancestral Haplogroup}} {{legend|#ff7a7a|Haplogroup A (Hg A)}}{{legend|#0085ff|Haplogroup B (Hg B)}} All of these molecules are part of the ancestral haplogroup, but at some point in the past a mutation occurred in the ancestral molecule, mutation A, which produced a new lineage, this is haplogroup A and is defined by mutation A, at some more recent point in the past a new mutation, mutation B, occurred in a person carrying haplogroup A, mutation B defined haplogroup B, haplogroup B is a subgroup, or subclade of haplogroup A, both haplogrups A and B are subclades of the ancestral haplogroup.]] The Y chromosome and mtDNA therefore share certain properties. Other chromosomes, [[autosomes]] and [[X chromosomes]] in women, share their genetic material (called [[Chromosomal crossover|crossing over]] leading to recombination) during [[meiosis]] (a special type of [[cell division]] that occurs for the purposes of [[sexual reproduction]]). Effectively this means that the genetic material from these chromosomes gets mixed up in every generation, and so any new mutations are passed down randomly from parents to offspring. The special feature that both Y chromosomes and mtDNA display is that mutations can accrue along a certain segment of both molecules and these mutations remain fixed in place on the DNA. Furthermore the historical sequence of these mutations can also be inferred. For example, if a set of ten Y chromosomes (derived from ten different men) contains a mutation, A, but only five of these chromosomes contain a second mutation, B, it must be the case that mutation B occurred after mutation A. Furthermore all ten men who carry the chromosome with mutation A are the direct male line descendants of the same man who was the first person to carry this mutation. The first man to carry mutation B was also a direct male line descendant of this man, but is also the direct male line ancestor of all men carrying mutation B. Series of mutations such as this form molecular lineages. Furthermore each mutation defines a set of specific Y chromosomes called a haplogroup. All men carrying mutation A form a single haplogroup, all men carrying mutation B are part of this haplogroup, but mutation B also defines a more recent haplogroup (which is a subgroup or subclade) of its own which men carrying only mutation A do not belong to. Both mtDNA and Y chromosomes are grouped into lineages and haplogroups, these are often presented as tree like diagrams.
Groundbreaking work by molecular biologists such as Cann ''et al.'' (1987)<ref>Rebecca L. Cann, Mark Stoneking, Allan C. Wilson (1987) ''[http://artsci.wustl.edu/~landc/html/cann/ Mitochondrial DNA and human evolution]'' in ''Nature'' '''325''': 31-36) </ref> on mtDNA produced three interesting observations relevant to race and human evolution.
Firstly, by estimating the rate at which mutations occur in mtDNA Cann ''et al.'' were able to estimate the age of the common ancestral mtDNA type: "the common ancestral mtDNA (type a) links mtDNA types that have diverged by an average of nearly 0.57%. Assuming a rate of 2%-4% per million years, this implies that the common ancestor of all surviving mtDNA types existed 140,000-290,000 years ago." This observation is robust, and this common direct female line ancestor (or mitochondrial [[most recent common ancestor]] (mtMRCA)) of all extant humans has become known as [[mitochondrial eve]]. The observation that the mtMRCA is the direct matrilineal ancestor of all living humans should not be interpreted as meaning that either she was the first anatomically modern human, nor that there were no other female humans living concurrently with her. A more reasonable explanation is that other women who lived at the same time as mtMRCA did indeed reproduce and pass their genes down to living humans, but that their mitochondrial lineages have been lost over time, probably due to random events such as producing only male children. It is impossible to know to what extent these non-extant lineages have been lost or how much they differed from the mtDNA of our mtMRCA. Cann ''et al.''
Secondly Cann ''et al.'' postulate that their work supports an African origin for modern human mtDNA: "We infer from the tree of minimum length... that Africa is a likely source of the human mitochondrial gene pool. This inference comes from the observation that one of the two primary branches leads exclusively to African mtDNAs... while the second primary branch also leads to African mtDNAs... By postulating that the common ancestral mtDNA (type a in Fig. 3) was African, we minimize the number of intercontinental migrations needed to account for the geographic distribution of mtDNA types."
Thirdly the study shows that mtDNA types (haplogroups) do not cluster by geography, ethnicity or race, implying multiple female lineages were involved in founding modern human populations, with many closely related lineages spread geographically and many populations containing distantly related lineages: "The second implication of the tree (Fig. 3) -that each non-African population has multiple origins-can be illustrated most simply with the New Guineans. Take, as an example, mtDNA type 49, a lineage whose nearest relative is not in New Guinea, but in Asia (type 50). Asian lineage 50 is closer genealogically to this New Guinea lineage than to other Asian mtDNA lineages. Six other lineages lead exclusively to New Guinean mtDNAs, each originating at a different place in the tree (types 12, 13, 26-29, 65, 95 and 127-134 in Fig. 3). This small region of New Guinea (mainly the Eastern Highlands Province) thus seems to have been colonised by at least seven maternal lineages (Tables 2 and 3). In the same way, we calculate the minimum numbers of female lineages that colonised Australia, Asia and Europe (Tables 2 and 3). Each estimate is based on the number of region-specific clusters in the tree (Fig. 3, Tables 2 and 3). These numbers, ranging from 15 to 36 (Tables 2 and 3), will probably rise as more types of human mtDNA are discovered."
The Y chromosome is much larger than mtDNA, and is relatively homogeneous, therefore it has taken much longer to find distinct lineages and to analyse them. Conversely, because the Y chromosome is so large by comparison it can hold a great deal more genetic information. With regard to the three observations made by Cann ''et al.'' concerning mtDNA, Y chromosome studies show similar patterns. The estimate for the age of the ancestral Y chromosome for all extant Y chromosomes is given at about 70,000 years ago and is also placed in Africa, this individual is sometimes referred to as [[Y chromosome Adam]]. The difference in dates between Y chromosome Adam and mitochondrial Eve is usually attributed to a higher extinction rate for Y chromosomes due to greater differential reproductive success between individual men, that means that a small number of very successful men may produce a great many children, while a larger number of less successful men will produce far less children. Keita ''et al.'' (2004) say, with reference to Y chromosome and mtDNA and concepts of race:{{quotation|Y-chromosome and mitochondrial DNA genealogies are especially interesting because they demonstrate the lack of concordance of lineages with morphology and facilitate a phylogenetic analysis. Individuals with the same morphology do not necessarily cluster with each other by lineage, and a given lineage does not include only individuals with the same trait complex (or 'racial type'). Y-chromosome DNA from Africa alone suffices to make this point. Africa contains populations whose members have a range of external phenotypes. This variation has usually been described in terms of 'race' (Caucasoids, Pygmoids, Congoids, Khoisanoids). But the Y-chromosome clade defined by the PN2 transition (PN2/M35, PN2/M2) [see [[Haplogroup E3b (Y-DNA)|haplogroup E3b]] and [[Haplogroup E3a (Y-DNA)|Haplogroup E3a]]] shatters the boundaries of phenotypically defined races and true breeding populations across a great geographical expanse21. African peoples with a range of skin colors, hair forms and physiognomies have substantial percentages of males whose Y chromosomes form closely related clades with each other, but not with others who are phenotypically similar. The individuals in the morphologically or geographically defined 'races' are not characterized by 'private' distinct lineages restricted to each of them.<ref>[http://www.nature.com/ng/journal/v36/n11s/full/ng1455.html Conceptualizing human variation]'' (2004) by S O Y Keita, R A Kittles1, C D M Royal, G E Bonney, P Furbert-Harris, G M Dunston & C N Rotimi in Nature Genetics '''36''', S17 - S20</ref>}}
==== How much are genes shared? Clustering analyses and what they tell us ====
{{Infobox multi locus allele clusters}}
[[Image:Rosenberg2007.png|thumb|left|150px|Clustering analysis from Rosenberg (2006), there are seven clusters and most individuals belong to several clusters. Note the [[Kalash]] have majority membership in a cluster in which individuals from other groups have only a tiny membership.]]
Genetic data can be used to infer population structure and assign individuals to groups that often correspond with their self-identified geographical ancestry. Recently, Lynn Jorde and Steven Wooding argued that "Analysis of many loci now yields reasonably accurate estimates of genetic similarity among individuals, rather than populations. Clustering of individuals is correlated with geographic origin or ancestry."<ref name="jorde">Lynn B Jorde & Stephen P Wooding, 2004, "Genetic variation, classification and 'race'" in ''Nature Genetics'' 36, S28 - S33 [http://www.nature.com/ng/journal/v36/n11s/full/ng1435.html Genetic variation, classification and 'race']</ref>
In 2003 [[A. W. F. Edwards]] wrote a paper called [[Lewontin's Fallacy]], rebuking the argument that because most of the variation is within group classification of humans is not possible. He claimed that this conclusion ignores the fact that most of the information that distinguishes populations is hidden in the [[correlation]] structure of the data and not simply in the variation of the individual factors. Edwards concludes that "It is not true that 'racial classification is ... of virtually no genetic or taxonomic significance' or that 'you can't predict someone’s race by their genes'."<ref>[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12879450&dopt=Abstract "Human genetic diversity: Lewontin's fallacy."], Edwards AW., Gonville and Caius College, Cambridge, in ''PubMed'', 2003 Aug;25(8):798-801.</ref> Likewise [[Neil Risch]] of [[Stanford University]] has proposed that self-identified race/ethnic group could be a valid means of categorization in the USA for public health and policy considerations.<ref>''[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1196372 Genetic Structure, Self-Identified Race/Ethnicity, and Confounding in Case-Control Association Studies]'' by Hua Tang, Tom Quertermous, Beatriz Rodriguez, Sharon L. R. Kardia, Xiaofeng Zhu, Andrew Brown, James S. Pankow, Michael A. Province, Steven C. Hunt, Eric Boerwinkle, Nicholas J. Schork, and Neil J. Risch Am J Hum Genet. 2005 February; 76(2): 268–275.</ref><ref>''[http://genomebiology.com/2002/3/7/comment/2007 Categorization of humans in biomedical research: genes, race and disease]'' by Neil Risch, Esteban Burchard, Elad Ziv and Hua Tang]'' Genome Biology 2002, 3:comment</ref> While a 2002 paper by [[Noah Rosenberg]]'s group makes a similar claim "The structure of human populations is relevant in various epidemiological contexts. As a result of variation in frequencies of both genetic and nongenetic risk factors, rates of disease and of such phenotypes as adverse drug response vary across populations. Further, information about a patient’s population of origin might provide health care practitioners with information about risk when direct causes of disease are unknown."<ref>Noah A. Rosenberg, Jonathan K. Pritchard, James L. Weber, Howard M. Cann, Kenneth K. Kidd, Lev A. Zhivotovsky, Marcus W. Feldman. ''Genetic Structure of Human Populations. Science'' (2002) '''298''':2381-5</ref>
Researchers such as [[Neil Risch]] and [[Noah Rosenberg]] have argued that a person's biological and cultural background may have important implications for medical treatment decisions, for example an opinion paper by Neil Risch's group in 2002 states: {{quotation|Both for genetic and non-genetic reasons, we believe that racial and ethnic groups should not be assumed to be equivalent, either in terms of disease risk or drug response.....Whether African Americans, Hispanics, Native Americans, Pacific Islanders or Asians respond equally to a particular drug is an empirical question that can only be addressed by studying these groups individually.<ref>Risch, N., Burchard, E., Ziv, E. & Tang, H. Categorization of humans in biomedical research: genes, race, and disease. Genome Biol. 3, 1−12 (2003)</ref>}} While another 2002 paper by Noah Rosenberg's group makes a similar claim {{quotation|The structure of human populations is relevant in various epidemiological contexts. As a result of variation in frequencies of both genetic and nongenetic risk factors, rates of disease and of such phenotypes as adverse drug response vary across populations. Further, information about a patient’s population of origin might provide health care practitioners with information about risk when direct causes of disease are unknown.<ref>Noah A. Rosenberg, Jonathan K. Pritchard, James L. Weber, Howard M. Cann, Kenneth K. Kidd, Lev A. Zhivotovsky, Marcus W. Feldman. ''Genetic Structure of Human Populations. Science'' (2002) '''298''':2381-5</ref>}} This work used samples from the [[Human Genome Diversity Project]] (HGDP), a project that has collected samples from individuals from 52 [[ethnic group]]s from various locations around the world. The HGDP has itself been criticised for collecting samples on an "ethnic group" basis, on the grounds that ethnic groups represent constructed categories rather than categories which are solely natural or biological. The [[Molecular anthropology|molecular anthropologist]] [[Jonathan Marks]] states: {{quotation|As any anthropologist knows, ethnic groups are categories of human invention, not given by nature. Their boundaries are porous, their existence historically ephemeral. There are the French, but no more Franks; there are the English, but no Saxons; and Navajos, but no Anasazi...we cannot really know the nature of the actual relationship of the modern group to the ancient one...The worst mistake you can make in human biology is to confuse constructed categories with natural ones. And to overload a big project with cultural categories as the overall sampling strategy would be a serious problem<ref>Marks, J. (2002) ''What it means to be 98% chimpanzee'' (paperback ed.) pp.202-203. Berkley. University of California Press.</ref>}} In the same issue of ''[[Science (journal)|Science]]'' that published the Rosenberg data, Mary-Claire King and Arno G. Motulsky give a similar warning regarding the HGDP data: {{quotation|The identification of clusters corresponding to the major geographic regions may depend on the sampling of individuals from well-defined, relatively homogeneous populations. If individuals were sampled from a worldwide 'grid' (or a worldwide grid weighted by population density), the clusters might be much less precisely defined. Does the correspondence of worldwide genetic clusters and major geographic regions suggest borders around genetic clusters analogous to the physical borders—oceans, mountain ranges, and deserts—separating geographic regions? No. Both the results of Rosenberg and colleagues and those of previous studies indicate that unlike separations between geographic regions, differences in allele frequencies are gradual.<ref>Mary-Claire King and Arno G. Motulsky ''Mapping Human History. Science'' (2002) '''298''': pp. 2342 - 2343. {{DOI|10.1126/science.1080373}}</ref>}}
Another study by [[Neil Risch]] in 2005 used 326 [[microsatellite]] markers and self-identified race/ethnic group (SIRE), white (European American), African-American (black), Asian and Hispanic (individuals involved in the study had to choose from one of these categories), to representing discrete "populations", and showed distinct and non-overlapping clustering of the white, African-American and Asian samples. The results were claimed to confirm the integrity of self-described ancestry: "We have shown a nearly perfect correspondence between genetic cluster and SIRE for major ethnic groups living in the United States, with a discrepancy rate of only 0.14%." But also warned that: "This observation does not eliminate the potential for confounding in these populations. First, there may be subgroups within the larger population group that are too small to detect by cluster analysis. Second, there may not be discrete subgrouping but continuous ancestral variation that could lead to stratification bias. For example, African Americans have a continuous range of European ancestry that would not be detected by cluster analysis but could strongly confound genetic case-control studies. (Tang, 2005)
Studies such as those by Risch and Rosenberg use a computer program called STRUCTURE to find human populations (gene clusters). It is a statistical program that works by placing individuals into one of two clusters based on their overall genetic similarity, many possible pairs of clusters are tested per individual to generate multiple clusters.<ref name="Witherspoon">"Genetic Similarities Within and Between Human Populations" (2007) by D.J. Witherspoon, S. Wooding, A.R. Rogers, E.E. Marchani, W.S. Watkins, M.A. Batzer and L.B. Jorde. ''Genetics.'' '''176'''(1): 351–359.</ref> These populations are based on multiple genetic markers that are often shared between different human populations even over large geographic ranges. The notion of a genetic cluster is that people within the cluster share on average similar allele frequencies to each other than to those in other clusters. (Edwards, 2003 but see also infobox "Multi Locus Allele Clusters") In a test of idealised populations, the computer programme STRUCTURE was found to consistently under-estimate the numbers of populations in the data set when high migration rates between populations and slow mutation rates (such as [[single nucleotide polymorphism]]s) were considered.<ref name="population?">Wapples, R., S. and Gaggiotti, O. ''What is a population? An empirical evaluation of some genetic methods for identifying the number of gene pools and their degree of connectivity Molecular Ecology'' (2006) '''15:''' 1419–1439. {{doi|10.1111/j.1365-294X.2006.02890.x}}</ref>
Nevertheless the Rosenberg ''et al.'' (2002) paper shows that individuals can be assigned to specific clusters to a high degree of accuracy. One of the underlying questions regarding the distribution of human genetic diversity is related to the degree to which genes are shared between the observed clusters. It has been observed repeatedly that the majority of variation observed in the global human population is found within populations. This variation is usually calculated using [[Sewall Wright]]'s [[Fixation index]] (F<sub>ST</sub>), which is an estimate of between to within group variation. The degree of human genetic variation is a little different depending upon the gene type studied, but in general it is common to claim that ~85% of genetic variation is found within groups, ~6-10% between groups within the same continent and ~6-10% is found between continental groups. For example The Human Genome Project states "two random individuals from any one group are almost as different [genetically] as any two random individuals from the entire world."<ref name="witherspoon">''[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1893020 Genetic Similarities Within and Between Human Populations]'' by D. J. Witherspoon, S. Wooding, A. R. Rogers, E. E. Marchani, W. S. Watkins, M. A. Batzer, and L. B. Jorde Genetics. 2007 May; 176(1): 351–359.</ref> On the other hand Edwards (2003) claims in his essay "[[Lewontin's Fallacy]]" that: "It is not true, as ''Nature'' claimed, that 'two random individuals from any one group are almost as different as any two random individuals from the entire world'" and Risch ''et al.'' (2002) state "Two Caucasians are more similar to each other genetically than a Caucasian and an Asian." It should be noted that these statements are not the same. Risch ''et al.'' simply state that two [[Indigenous peoples|indigenous]] individuals from the same geographical region are more similar to each other than either is to an indigenous individual from a different geographical region, a claim few would argue with. Jorde et al put it like this:
{{quotation|The picture that begins to emerge from this and other analyses of human genetic variation is that variation tends to be geographically structured, such that most individuals from the same geographic region will be more similar to one another than to individuals from a distant region.<ref name="jorde"/>}}
Whereas Edwards claims that it is not true that the differences between individuals from different geographical regions represent only a small proportion of the variation within the human population (he claims that within group differences between individuals are not almost as large as between group differences). Bamshad ''et al.'' (2004) used the data from Rosenberg ''et al.'' (2002) to investigate the extent of genetic differences between individuals within continental groups relative to genetic differences between individuals between continental groups. They found that though these individuals could be classified very accurately to continental clusters, there was a significant degree of genetic overlap on the individual level, to the extent that, using 377 loci, individual Europeans were about 38% of the time more genetically similar to East Asians than to other Europeans.
The results obtained by clustering analyses are dependent on several criteria:
* The clusters produced are relative clusters and not absolute clusters, each cluster is the product of comparisons between sets of data derived for the study, results are therefore highly influenced by sampling strategies. (Edwards, 2003)
* The geographic distribution of the populations sampled, because human genetic diversity is marked by isolation by distance, populations from geographically distant regions will form much more discrete clusters than those from geographically close regions. (Kittles and Weiss, 2003)
* The number of genes used. The more genes used in a study the greater the resolution produced and therefore the greater number of clusters that will be identified. (Tang, 2005)
[[Image:Bauchet European clusters.png|thumb|400px|left|Distribution of European clusters identified by Bauchet. When two clusters are identified there is a north-southeast cline that may be due to [[demic diffusion]] during the [[Neolithic Europe|European Neolithic]]]]Additionally two studies of European population clusters have been produced. Seldin ''et al.'' (2006) identified three European clusters using 5,700 genome-wide polymorphisms. Bauchet ''et al.'' (2007) used 10,000 polymorphisms to identify five distinct clusters in the European population, consisting of a south-eastern European cluster (including samples from southern Italians, Armenian, [[Ashkenazi]] Jewish and Greek "populations"); a northern-European Cluster (including samples from German, eastern English, Polish and western Irish "populations"); a Basque cluster (including samples from Basque "populations"); a Finnish cluster (including samples from Finnish "populations") and a Spanish cluster (including samples from Spanish "populations"). Most "populations" contained individuals from clusters other than the dominant cluster for that population, there were also individuals with membership of several clusters. The results of this study are presented on a map of Europe. (Bauchet, 2007)
The existence of allelic clines and the observation that the bulk of human variation is continuously distributed, has led some scientists to conclude that any categorization schema attempting to partition that variation meaningfully will necessarily create artificial truncations. (Kittles & Weiss 2003). It is for this reason, Reanne Frank argues, that attempts to allocate individuals into ancestry groupings based on genetic information have yielded varying results that are highly dependent on methodological design.<ref name="Frank">[http://paa2006.princeton.edu/download.aspx?submissionId=61713 Back with a Vengeance: the Reemergence of a Biological Conceptualization of Race in Research on Race/Ethnic Disparities in Health Reanne Frank]</ref> Serre and Pääbo (2004) make a similar claim:{{quotation|The absence of strong continental clustering in the human gene pool is of practical importance. It has recently been claimed that “the greatest genetic structure that exists in the human population occurs at the racial level” (Risch et al. 2002). Our results show that this is not the case, and we see no reason to assume that “races” represent any units of relevance for understanding human genetic history.}}
In a response to Serre and Pääbo (2004), Rosenberg ''et al.'' (2005) make three relevant observations. Firstly they maintain that their clustering analysis is robust. Secondly they agree with Serre and Pääbo that membership of multiple clusters can be interpreted as evidence for clinality (isolation by distance), though they also comment that this may also be due to admixture between neighbouring groups (small island model). Thirdly they comment that evidence of clusterdness is not evidence for any concepts of "biological race". {{quotation|Serre and Pääbo argue that human genetic diversity consists of clines of variation in allele frequencies. We agree and had commented on this issue in our original paper: “In several populations, individuals had partial membership in multiple clusters, with similar membership coefficients for most individuals. These populations might reflect continuous gradations across regions or admixture of neighboring groups.” (Rosenberg, 2002) At the same time, we find that human genetic diversity consists not only of clines, but also of clusters, which STRUCTURE observes to be repeatable and robust....Our evidence for clustering should not be taken as evidence of our support of any particular concept of “biological race.” In general, representations of human genetic diversity are evaluated based on their ability to facilitate further research into such topics as human evolutionary history and the identification of medically important genotypes that vary in frequency across populations. Both clines and clusters are among the constructs that meet this standard of usefulness: for example, clines of allele frequency variation have proven important for inference about the genetic history of Europe, and clusters have been shown to be valuable for avoidance of the false positive associations that result from population structure in genetic association studies. The arguments about the existence or nonexistence of “biological races” in the absence of a specific context are largely [[wikt:orthogonal|orthogonal]] to the question of scientific utility, and they should not obscure the fact that, ultimately, the primary goals for studies of genetic variation in humans are to make inferences about human evolutionary history, human biology, and the genetic causes of disease.<ref name="rosenberg2005>''Rosenberg NA, Mahajan S, Ramachandran S, Zhao C, Pritchard JK, ''et al.'' (2005) ''Clines, Clusters, and the Effect of Study Design on the Inference of Human Population Structure. PLoS Genet'' '''1(6)''': e70 {{doi|10.1371/journal.pgen.0010070}}</ref>}}
Similarly Witherspoon ''et al.'' (2007) have shown that while it is possible to classify people into genetic clusters this does not resolve the observation that any two individuals from different populations are often genetically more similar to each other than to two individuals from the same population:{{quotation|Discussions of genetic differences between major human populations have long been dominated by two facts: (a) Such differences account for only a small fraction of variance in allele frequencies, but nonetheless (b) multilocus statistics assign most individuals to the correct population. This is widely understood to reflect the increased discriminatory power of multilocus statistics. Yet Bamshad et al. (2004) showed, using multilocus statistics and nearly 400 polymorphic loci, that (c) pairs of individuals from different populations are often more similar than pairs from the same population. If multilocus statistics are so powerful, then how are we to understand this finding?<br> All three of the claims listed above appear in disputes over the significance of human population variation and "race"...The Human Genome Project (2001, p. 812) states that "two random individuals from any one group are almost as different [genetically] as any two random individuals from the entire world."<ref name="witherspoon"/>}}
Risch ''et al.'' (2002) state that "two Caucasians are more similar to each other genetically than a Caucasian and an Asian", but Bamshad ''et al'' (2004)<ref name="bamshad 2004">Bamshad, Wooding, Salisbury§ and Stephens (2004) ''Deconstructing the relationship between genetics and race. Nature Reviews Genetics'' '''8''':598-609. {{doi|10.1038/nrg1401}}</ref> used the same data set as Rosenberg ''et al.'' (2002) to show that Europeans are more similar to Asians 38% of the time than they are to other Europeans when only 377 microsatellite markers are analysed.
[[Image:IBD SIM.png|thumb|right|200px|If a landmass is considered with variation distributed in one dimension (west-east). Top: Distribution of genetic variation if a small island model is considered, there are two "populations" with a narrow region of hybridisation where migration occurs, this pattern is clustered. Bottom: Distribution of genetic variation if isolation by distance is considered, all variation is gradual over the extent of the landmass, this pattern is clinal.]]
{| class="wikitable" style="text-align:center"
|+ Percentage similarity between two individuals from different clusters when 377 microsatellite markers are considered.<ref>The table gives the percentage likelihood that two individuals from different clusters are genetically more similar to each other than to someone from their own population when 377 microsatellite markers are considered from Bamshad ''et al.'' (2004){{doi|10.1038/nrg1401}}, original data from Rosenberg (2002).</ref>
|-
! x !! Africans !! Europeans !! Asians
|-
! Europeans
| 36.5 || — || —
|-
! Asians
| 35.5 || 38.3 || —
|-
! Indigenous Americans
| 26.1 || 33.4 || 35
|}
In agreement with the observation of Bamshad ''et al.'' (2004), Witherspoon ''et al.'' (2007) have shown that many more than 326 or 377 microsatellite loci are required in order to show that individuals are always more similar to individuals in their own population group than to individuals in different population groups, even for three distinct populations.<ref name="witherspoon">''[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1893020 Genetic Similarities Within and Between Human Populations]'' by D. J. Witherspoon, S. Wooding, A. R. Rogers, E. E. Marchani, W. S. Watkins, M. A. Batzer, and L. B. Jorde Genetics. 2007 May; 176(1): 351–359.</ref>
In 2007 Witherspoon ''et al.'' sought to investigate these apparently contradictory observations. In their paper ''Genetic similarities within and between human populations''<ref name="witherspoon"/> they expand upon the observation of Bamshad ''et al.'' (2004). They show that the observed clustering of human populations into relatively discrete groups is a product of using what they call "population trait values". This means that each individual is compared to the "typical" trait for several populations, and assigned to a population based on the individual's overall similarity to one of the populations as a whole: "population membership is treated as an additive quantitative genetic trait controlled by many loci of equal effect, and individuals are divided into populations on the basis of their trait values." They therefore claim that clustering analyses cannot necessarily be used to make inferences regarding the similarity or dissimilarity of individuals between or within clusters, but only for similarities or dissimilarities of individuals to the "trait values" of any given cluster. The paper measures the rate of misclassification using these "trait values" and calls this the "population trait value misclassification rate" (C<sub>T</sub>). The paper investigates the similarities between individuals by use of what they term the "dissimilarity fraction" (ω): "the probability that a pair of individuals randomly chosen from different populations is genetically more similar than an independent pair chosen from any single population." Witherspoon ''et al.'' show that two individuals can be more genetically similar to each other than to the typical genetic type of their own respective populations, and yet be correctly assigned to their respective populations. An important observation is that the likelihood that two individuals from different populations will be more similar to each other genetically than two individuals from the same population depends on several criteria, most importantly the number of genes studied and the distinctiveness of the populations under investigation.{{quotation|Given 10 loci, three distinct populations, and the full spectrum of polymorphisms, the answer is ω ~ 0.3, or nearly one-third of the time. With 100 loci, the answer is ~20% of the time and even using 1000 loci, ω ~ 10%. However, if genetic similarity is measured over many thousands of loci, the
answer becomes ''never'' when individuals are sampled from geographically separated populations.}}
By geographically separated populations, they mean sampling of people only from distant geographical regions while omitting intermediate regions, in this case Europe, sub-Saharan Africa, and East Asian. They continue:
{{quotation|On the other hand, if the entire world population were analyzed, the inclusion of many closely related and admixed populations would increase ω... In a similar vein, Romualdi ''et al.'' (2002) and Serre and Paabo (2004) have suggested that highly accurate classification of individuals from continuously sampled (and therefore closely related) populations may be impossible.... Classification methods typically make use of aggregate properties of populations, not just properties of individuals or even of pairs of individuals... The Structure classification algorithm (Pritchard et al. 2000) also relies on aggregate properties of populations, such as Hardy–Weinberg and linkage equilibrium. In contrast, the pairwise distances used to compute ω make no use of population-level information and are strongly affected by the high level of within-groups variation typical of human populations. This accounts for the difference in behavior between ω and the classification results.}}
Witherspoon ''et al.'' also add: {{quotation|given enough genetic data, individuals can be correctly assigned to their populations of origin is compatible with the observation that most human genetic variation is found within populations, not between them. It is also compatible with our finding that, even when the most distinct populations are considered and hundreds of loci are used, individuals are frequently more similar to members of other populations than to members of their own population.}}
===Summary of different biological definitions of race===
{| class="wikitable"
|+ Biological definitions of race (Long & Kittles, 2003) ''et al.''
! Concept || Reference || Definition
|-
| Essentialist || Hooton (1926) || "A great division of mankind, characterized as a group by the sharing of a certain combination of features, which have been derived from their common descent, and constitute a vague physical background, usually more or less obscured by individual variations, and realized best in a composite picture."
|-
| Taxonomic || [[Ernst Mayr|Mayr]] (1969) || "An aggregate of phenotypically similar populations of a species, inhabiting a geographic subdivision of the range of a species, and differing taxonomically from other populations of the species."
|-
| Population || [[Theodosius Dobzhansky|Dobzhansky]] (1970) || "Races are genetically distinct Mendelian populations. They are neither individuals nor particular genotypes, they consist of individuals who differ genetically among themselves."
|-
| Lineage || Templeton (1998) || "A subspecies (race) is a distinct evolutionary lineage within a species. This definition requires that a subspecies be genetically differentiated due to barriers to genetic exchange that have persisted for long periods of time; that is, the subspecies must have historical continuity in addition to current genetic differentiation."
|}
=== Current views across disciplines ===
One result of debates over the meaning and validity of the concept "race" is that the current literature across different disciplines regarding human variation lacks [[scientific consensus|consensus]], though within some fields, such as biology, there is strong consensus. Some studies use the word race in its early [[essentialism|essentialist]] [[taxonomic]] sense. Many others still use the term race, but use it to mean a population, [[clade]], or [[haplogroup]]. Others eschew the concept of race altogether, and use the concept of population as a less problematical unit of analysis.
Since 1932, some [[college]] [[textbook]]s introducing physical anthropology have increasingly come to reject race as a valid concept: from 1932 to 1976, only seven out of thirty-two rejected race; from 1975 to 1984, thirteen out of thirty-three rejected race; from 1985 to 1993, thirteen out of nineteen rejected race. According to one academic journal entry, where 78 percent of the articles in the 1931 ''Journal of Physical Anthropology'' employed these or nearly synonymous terms reflecting a bio-race paradigm, only 36 percent did so in 1965, and just 28 percent did in 1996.<ref>Leonard Lieberman, Rodney C. Kirk, and Alice Littlefield, "Perishing Paradigm: Race—1931-99," ''American Anthropologist'' 105, no. 1 (2003): 110-13. A following article in the same issue, by Mat Cartmill and Kaye Brown, questions the precise rate of decline, but from their biased perspective agree that the Negroid/Caucasoid/Mongoloid paradigm has fallen into near-total disfavor.</ref> The American Anthropological Association, drawing on biological research, currently holds that "The concept of race is a social and cultural construction... . Race simply cannot be tested or proven scientifically," and that, "It is clear that human populations are not unambiguous, clearly demarcated, biologically distinct groups. The concept of 'race' has no validity ... in the human species".<ref name="AAAonRace">[http://www.aaanet.org/stmts/racepp.htm American Anthropological Association Statement on "Race"]</ref>
In an ongoing debate, some geneticists argue that race is neither a meaningful concept nor a useful [[heuristic]] device,<ref>(Wilson ''et al.'' 2001), (Cooper ''et al.'' 2003) (given in summary by Bamshad ''et al.'' 2004 p.599)</ref> and even that genetic differences among groups are biologically meaningless,<ref>(Schwartz 2001), (Stephens 2003) (given in summary by Bamshad ''et al.'' 2004 p.599)</ref> on the grounds that more genetic variation exists within such races than among them, and that racial traits overlap without discrete boundaries.<ref>(Smedley and Smedley 2005), (Helms ''et al.'' 2005), [http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-311X2004000300003&lng=es&nrm=iso]. Lewontin, for example argues that there is no biological basis for race on the basis of research indicating that more genetic variation exists within such races than among them (Lewontin 1972).</ref>
Other geneticists, in contrast, argue that categories of self-identified race/ethnicity or biogeographic ancestry are both valid and useful,<ref>(Risch ''et al.'' 2002), (Bamshad 2005). [[Neil Risch]] argues: "One could make the same arguments about sex and age! ... you can undermine any definitional system... In a recent study... we actually had a higher discordance rate between self-reported sex and markers on the X chromosome [than] between genetic structure [based on microsatellite markers] versus [racial] self-description, [which had a] 99.9% concordance... So you could argue that sex is also a problematic category. And there are differences between sex and gender; self-identification may not be correlated with biology perfectly. And there is sexism. And you can talk about age the same way. A person's chronological age does not correspond perfectly with his biological age for a variety of reasons, both inherited and non-inherited. Perhaps just using someone's actual birth year is not a very good way of measuring age. Does that mean we should throw it out? ... Any category you come up with is going to be imperfect, but that doesn't preclude you from using it or the fact that it has utility"(Gitschier 2005).</ref> that these categories correspond with clusters [[Race and genetics#Genetic variation is structured by geographic origin|inferred from multilocus genetic data]],<ref>(Harpending and Rogers 2000), (Bamshad ''et al.'' 2003), (Edwards 2003), (Bamshad ''et al.'' 2004), (Tang ''et al.'' 2005), (Rosenberg ''et al.'' 2005): "If enough markers are used... individuals can be partitioned into genetic clusters that match major geographic subdivisions of the globe".</ref> and that this correspondence implies that genetic factors might contribute to unexplained phenotypic variation between groups.<ref>(Mountain and Risch 2004)</ref>
In February, 2001, the editors of the medical journal ''Archives of Pediatrics and Adolescent Medicine'' asked authors to no longer use "race" as an explanatory variable and not to use obsolescent terms. Some other peer-reviewed journals, such as the ''New England Journal of Medicine'' and the ''American Journal of Public Health'', have made similar endeavours.<ref> Frederick P. Rivara and Laurence Finberg, "Use of the Terms Race and Ethnicity," ''Archives of Pediatrics & Adolescent Medicine'' 155, no. 2 (2001): 119. For similar author's guidelines, see Robert S. Schwartz, "Racial Profiling in Medical Research," ''The New England Journal of Medicine'', 344 (no, 18, May 3, 2001); M.T. Fullilove, "Abandoning 'Race' as a Variable in Public Health Research: An Idea Whose Time has Come," ''American Journal of Public Health'', 88 (1998), 1297-1298; and R. Bhopal and L. Donaldson, "White, European, Western, Caucasian, or What? Inappropriate Labeling in Research on Race, Ethnicity, and Health." ''American Journal of Public Health'', 88 (1998), 1303-1307.</ref> Furthermore, the National Institutes of Health recently issued a program announcement for grant applications through February 1, 2006, specifically seeking researchers who can investigate and publicize among primary care physicians the detrimental effects on the nation's health of the practice of medical racial profiling using such terms. The program announcement quoted the editors of one journal as saying that, "analysis by race and ethnicity has become an analytical knee-jerk reflex."<ref> See program announcement and requests for grant applications at the NIH website, at [http://grants1.nih.gov/grants/guide/pa-files/PA-03-057.html nih.gov].</ref>
A [[Statistical survey|survey]], taken in 1985 (Lieberman ''et al.'' 1992), asked 1,200 American anthropologists how many '''disagree''' with the following proposition: "There are biological races in the species ''Homo sapiens''." The responses were:
*'''[[physical anthropologist]]s 41%'''
*'''[[cultural anthropologist]]s 53%'''<ref>Bindon, Jim. University of Alabama. "[http://www.as.ua.edu/ant/bindon/ant275/presentations/POST_WWII.PDF#search=%22stanley%20marion%20garn%22 Post World War II"]. 2005. August 28, 2006.</ref>
The figure for physical anthropologists at [[PhD]] granting departments was slightly higher, rising from 41% to 42%, with 50% agreeing. This survey, however, did not specify any particular definition of race (although it did clearly specify ''biological race'' within the ''species'' ''Homo Sapiens''); it is difficult to say whether those who supported the statement thought of race in taxonomic or population terms.
The same survey, taken in 1999,<ref>[http://www.ssc.uwo.ca/psychology/faculty/rushtonpdfs/Lieberman2001CA.pdf ssc.uwo.ca]</ref> showed the following changing results for anthropologists:
*'''[[physical anthropologist]]s 69%'''
*'''[[cultural anthropologist]]s 80%'''
In [[Poland]] the race concept was rejected by only 25 percent of anthropologists in 2001, although: "Unlike the U.S. anthropologists, Polish anthropologists tend to regard race as a term without taxonomic value, often as a substitute for population."<ref>"'Race'—Still an Issue for Physical Anthropology? Results of Polish Studies Seen in the Light of the U.S. Findings" by Katarzyna A. Kaszycka. American Anthropologist March 2003, Vol. 105, No. 1, pp. 116-124</ref>
In the face of these issues, some evolutionary scientists have simply abandoned the concept of race in favor of "[[Population genetics|population]]." What distinguishes population from previous groupings of humans by race is that it refers to a breeding population (essential to genetic calculations) and not to a biological [[taxon]]. Other evolutionary scientists have abandoned the concept of race in favor of [[cline (population genetics)|cline]] (meaning, how the frequency of a trait changes along a geographic gradient). (The concepts of population and cline are not, however, mutually exclusive and both are used by many evolutionary scientists.)
According to Jonathan Marks,
:By the 1970s, it had become clear that (1)most human differences were cultural; (2) what was not cultural was principally polymorphic - that is to say, found in diverse groups of people at different frequencies; (3) what was not cultural or polymorphic was principally clinal - that is to say, gradually variable over geography; and (4) what was left - the component of human diversity that was not cultural, polymorphic, or clinal - was very small.
:A consensus consequently developed among anthropologists and geneticists that race as the previous generation had known it - as largely discrete, geographically distinct, gene pools - did not exist.<ref> Marks, Jonathan (2007) "Grand Anthropological Themes" in ''American Ethnologist'' 34(2): 234, cf. Marks, Jonathan (1995) ''Human Biodiversity: Genes, Race, and History''. New York: Aldine de Gruyter</ref>
In the face of this rejection of race by evolutionary scientists, many social scientists have replaced the word race with the word "[[Ethnic group|ethnicity]]" to refer to self-identifying groups based on beliefs concerning shared culture, ancestry and history. Alongside empirical and conceptual problems with "race," following the [[Second World War]], evolutionary and social scientists were acutely aware of how beliefs about race had been used to justify discrimination, apartheid, slavery, and genocide. This questioning gained momentum in the 1960s during the U.S. [[civil rights movement]] and the emergence of numerous anti-colonial movements worldwide. They thus came to understood that these justifications, even when expressed in language that sought to appear objective, were [[Social construction|social constructs]].<ref name="Gordon64">Gordon 1964</ref>
===Races as social constructions===
{{main|Social interpretations of race|Racialism}}
Even as the idea of "race" was becoming a powerful organizing principle in many societies, the shortcomings of the concept were apparent. In the Old World, the gradual transition in appearances from one group to adjacent groups emphasized that "one variety of mankind does so sensibly pass into the other, that you cannot mark out the limits between them," as Blumenbach observed in his writings on human variation (Marks 1995, p. 54). As anthropologists and other evolutionary scientists have shifted away from the language of race to the term ''population'' to talk about genetic differences, [[History|Historians]], [[cultural anthropology|anthropologists]] and [[social sciences|social scientists]] have re-conceptualized the term "race" as a cultural category or [[social construct]], in other words, as a particular way that some people have of talking about themselves and others. As Stephan Palmie has recently summarized, race "is not a thing but a social relation";<ref name="Palmie07">Palmie, Stephan (2007) "Genomics, Divination, 'Racecraft'" in ''American Ethnologist'' 34(2): 214</ref> or, in the words of Katya Gibel Mevorach, "a metonym," "a human invention whose criteria for differentiation are neither universal nor fixed but have always been used to manage difference."<ref name="Mevorach07">Mevorach, Katya Gibel (2007) "Race, Racism and Academic Complicity" in ''American Ethnologist'' 34(2): 239-240</ref> As such it cannot be a useful analytical concept; rather, the use of the term "race" itself must be analyzed. Moreover, they argue that biology will not explain why or how people use the idea of race: history and social relationships will. For example, the fact that in many parts of the United States, categories such as [[Hispanics in the United States|Hispanic]] or [[Latino]] are viewed to constitute a race (instead of an [[Ethnicity|ethnic group]]) reflect this new idea of "race as a social construct". However, it may be in the interest of dominant groups to cluster [[Spanish Language|Spanish speakers]] into a single, isolated population, rather than classifying them according to [[Typology (anthropology)|Race]] (as are the rest of U.S. racial groups). Especially in the context of [[United States immigration debates|the debate over immigration]]. "According to the 2000 census, two-thirds [of Hispanics] are of Mexican heritage . . . So, for practical purposes, when we speak of Hispanics and Latinos in the U.S., we’re really talking about [[Indigenous peoples of the Americas|Native Americans]] . . . [therefore] if being Hispanic carries any societal consequences that justify inclusion in the pantheon of great American racial minorities, they’re the result of having Native American blood. [But imagine the] the impact this would have on the illegal-immigration debate. It’s one thing to blame the fall of western civilization on illegal Mexican immigration, but quite thornier to blame it on illegal [[Amerindian]] immigration from Mexico."<ref>Separated by a common language: The case of the white Hispanic By Alfredo Tryferis [http://www.rawstory.com/exclusives/tryferis/hispanic.htm]</ref>
==== In the United States ====
{{main|Race in the United States}}
:''see also [[Race and genetics#Admixture in the United States|Admixture in the United States]]''
The immigrants to the New World came largely from widely separated regions of the Old World—western and [[northern Europe]], [[West Africa]], and, later, [[eastern Asia]] and [[southern Europe]]. In the [[Americas]], the immigrant populations began to [[miscegenation|mix]] among themselves and with the [[indigenous peoples of the Americas|indigenous inhabitants of the continent]]. In the [[United States]], for example, most people who self-identify as [[African American]] have some [[European ethnic groups|European ancestors]] — in one analysis of genetic markers that have differing frequencies between continents, European ancestry ranged from an estimated 7% for a sample of [[Jamaicans]] to ∼23% for a sample of African Americans from [[New Orleans]] (Parra ''et al.'' 1998). Similarly, many people who identify as [[European American]] have some African or Native American ancestors, either through openly [[interracial marriage]]s or through the gradual inclusion of people with mixed ancestry into the majority population. In a survey of college students who self-identified as [[White people|white]] in a northeastern U.S. university, ∼30% were estimated to have less than 90% European ancestry.<ref name="Shriver03">Shriver ''et al.'' 2003</ref>
In the United States since its early history, Native Americans, African-Americans and European-Americans were classified as belonging to different races. For nearly three centuries, the criteria for membership in these groups were similar, comprising a person’s appearance, his fraction of known non-White ancestry, and his social circle.<sup>[[#2|2]]</sup> But the criteria for membership in these races diverged in the late 19th century. During Reconstruction, increasing numbers of Americans began to consider anyone with "[[one-drop theory|one drop]]" of known "Black blood" to be Black regardless of appearance.<sup>[[#3|3]]</sup> By the early 20th century, this notion of invisible blackness was made statutory in many states and widely adopted nationwide.<sup>[[#4|4]]</sup> In contrast, [[Amerindians]] continue to be defined by a certain percentage of "Indian blood" (called ''[[Blood quantum laws|blood quantum]]'') due in large part to [[American slavery ethics]]. Finally, for the past century or so, to be White one had to have perceived "pure" White ancestry.
Efforts to sort the increasingly mixed population of the United States into discrete categories generated many difficulties (Spickard 1992). By the standards used in past censuses, many millions of children born in the United States have belonged to a different race than have one of their biological parents. Efforts to track mixing between groups led to a proliferation of categories (such as "mulatto" and "octoroon") and "blood quantum" distinctions that became increasingly untethered from self-reported ancestry. A person's racial identity can change over time, and self-ascribed race can differ from assigned race (Kressin ''et al.'' 2003). Until the 2000 census, [[Latino (demonym)|Latinos]] were required to identify with a single race despite the long history of mixing in [[Latin America]]; partly as a result of the confusion generated by the distinction, 32.9% (U.S. census records) of Latino respondents in the 2000 census ignored the specified racial categories and checked "some other race". (Mays ''et al.'' 2003 claim a figure of 42%)
The difference between how Native American and Black identities are defined today (blood quantum versus one-drop) has demanded explanation. According to anthropologists such as [[Gerald Sider]], the goal of such racial designations was to concentrate power, wealth, privilege and land in the hands of Whites in a society of [[White privilege (sociology)|White hegemony and privilege]] (Sider 1996; see also Fields 1990). The differences have little to do with biology and far more to do with the history of [[racism]] and specific forms of [[White supremacy]] (the social, geopolitical and economic agendas of dominant Whites vis-à-vis subordinate Blacks and Native Americans) especially the different roles Blacks and Amerindians occupied in White-dominated 19th century America. The theory suggests that the blood quantum definition of Native American identity enabled Whites to acquire Amerindian lands, while the one-drop rule of Black identity enabled Whites to preserve their agricultural labor force. The contrast presumably emerged because as peoples transported far from their land and kinship ties on another continent, Black labor was relatively easy to control, thus reducing Blacks to valuable [[commodity|commodities]] as agricultural laborers. In contrast, Amerindian labor was more difficult to control; moreover, Amerindians occupied large territories that became valuable as agricultural lands, especially with the invention of new technologies such as railroads; thus, the blood quantum definition enhanced White acquisition of Amerindian lands in a doctrine of [[Manifest Destiny]] that subjected them to marginalization and multiple episodic localized campaigns of extermination.
The political economy of race had different consequences for the descendants of aboriginal Americans and African slaves. The 19th century blood quantum rule meant that it was relatively easier for a person of mixed Euro-Amerindian ancestry to be accepted as White. The offspring of only a few generations of intermarriage between Amerindians and Whites likely would not have been considered Amerindian at all (at least not in a legal sense). Amerindians could have [[treaty rights]] to land, but because an individual with one Amerindian great-grandparent no longer was classified as Amerindian, they lost any legal claim to Amerindian land. According to the theory, this enabled Whites to acquire Amerindian lands. The irony is that the same individuals who could be denied legal standing because they were "too White" to claim property rights, might still be Amerindian enough to be considered as "[[Half-breed|breeds]]", stigmatized for their Native American ancestry.
The 20th century one-drop rule, on the other hand, made it relatively difficult for anyone of known Black ancestry to be accepted as White. The child of a Black sharecropper and a White person was considered Black. And, significant in terms of the economics of sharecropping, such a person also would likely be a sharecropper as well, thus adding to the employer's labor force.
In short, this theory suggests that in a 20th century economy that benefited from sharecropping, it was useful to have as many Blacks as possible. Conversely, in a 19th century nation bent on westward expansion, it was advantageous to diminish the numbers of those who could claim title to Amerindian lands by simply defining them out of existence.
It must be mentioned, however, that although some scholars of the [[Jim Crow laws|Jim Crow period]] agree that the 20th century notion of invisible Blackness shifted the color line in the direction of paleness, thereby swelling the labor force in response to Southern Blacks' great migration northwards, others (Joel Williamson, C. Vann Woodward, George M. Fredrickson, Stetson Kennedy) see the one-drop rule as a simple consequence of the need to define Whiteness as being pure, thus justifying White-on-Black oppression. In any event, over the centuries when Whites wielded power over both Blacks and Amerindians and widely believed in their inherent superiority over people of color, it is no coincidence that the hardest racial group in which to prove membership was the White one.
In the United States, social and legal conventions developed over time that forced individuals of mixed ancestry into simplified racial categories (Gossett 1997). An example is the "[[one-drop rule]]" implemented in some state laws that treated anyone with a single known African American ancestor as black (Davis 2001). The decennial censuses conducted since 1790 in the United States also created an incentive to establish racial categories and fit people into those categories (Nobles 2000). In other countries in the Americas where mixing among groups was overtly more extensive, social categories have tended to be more numerous and fluid, with people moving into or out of categories on the basis of a combination of socioeconomic status, social class, ancestry, and appearance (Mörner 1967).
The term "[[Hispanic]]" as an [[ethnonym]] emerged in the 20th century with the rise of migration of laborers from American [[Spanish-speaking countries]] to the United States. It includes people who had been considered racially distinct (Black, White, Amerindian, Asian, and mixed groups) in their home countries. Today, the word "Latino" is often used as a synonym for "Hispanic". In contrast to "Latino"´or "Hispanic" "[[Anglo]]" is now used to refer to non-Hispanic [[White American]]s or non-Hispanic [[European American]]s, most of whom speak the English language but are not necessarily of [[English people|English]] descent.
==== In Brazil ====
{{main|Race in Brazil}}
Compared to 19th century United States, 20th century [[Demographics of Brazil|Brazil]] was characterized by a perceived relative absence of sharply defined racial groups. According to anthropologist Marvin Harris (1989), this pattern reflects a different history and different [[social relations]]. Basically, race in Brazil was "biologized," but in a way that recognized the difference between ancestry (which determines [[genotype]]) and [[phenotypic]] differences. There, racial identity was not governed by such a rigid descent rule as in the United States. A Brazilian child was never automatically identified with the racial type of one or both parents, nor were there only a very limited number of categories to choose from. Over a dozen racial categories would be recognized in conformity with all the possible combinations of hair color, hair texture, eye color, and skin color. These types grade into each other like the colors of the spectrum, and no one category stands significantly isolated from the rest. That is, race referred preferencially to appearance, not heredity.
Through this system of racial identification, parents and children and even brothers and sisters were frequently accepted as representatives of completely different racial types. In a fishing village in the state of [[Bahia]], an investigator showed 100 people pictures of three sisters and asked them to identify the races of each. In only six responses were the sisters identified by the same racial term. Fourteen responses used a different term for each sister (Harris 1964: 57). In another experiment nine portraits were shown to a hundred people. Forty different racial types were elicited (Harris 1964: 58). It was found, in addition, that a given Brazilian might be called by as many as thirteen different terms by other members of the community (Harris 1964: 57). These terms are spread out across practically the entire spectrum of theoretical racial types. A further consequence of the absence of a descent rule was that Brazilians apparently not only disagreed about the racial identity of specific individuals, but they also seemed to be in disagreement about the abstract meaning of the racial terms as defined by words and phrases. For example, 40% of a sample ranked ''[[moreno]] claro'' ("light" person of primarily European ancestry with dark hair) as a lighter type than ''[[mulato]] claro'' ("light" person of mixed European and African ancestry), while 60% reversed this order (Harris 1964: 58). A further note of confusion is that one person might employ different racial terms to describe the same person over a short time span (Harris 1964: 59; Goldstein 1999: 566-568).} [For a solid discussion of Brazilian racial terms, see Livio Sansone's ''Blackness Without Ethnicity'' (2003) and France Winddance Twine's ''Racism in a Racial Democracy'' (1998).] The choice of which racial description to use may vary according to the relationship (be it personal, class-based, or otherwise) between the speaker and the person concerned and moods of the individuals involved (Harris 1964: 59).
So, although the identification of a person by race is far more fluid and flexible in Brazil than in the U.S., there still are racial stereotypes and prejudices. African features have been considered less desirable; Blacks have been considered socially inferior, and Whites superior (Harris 1964: 59-60). These white [[supremacist]] values seem to be an obvious legacy of [[Portugal|Portuguese]] colonization and the slave-based [[plantation system]] (Harris 1964: 54-57). The complexity of racial classifications in Brazil is reflective of the extent of [[miscegenation]] in [[Brazilian society]], a society that remains highly, but not strictly, [[social stratification|stratified]] along color lines. Henceforth, the Brazilian [[narrative]] of a perfect "post-racist" country, must be met with caution, as sociologist [[Gilberto Freyre]] demonstrated in 1933 in ''Casa Grande e Senzala''.
====Marketing of race: genetic lineages as social lineages====
New research in molecular genetics, and the marketing of genetic identities through the analysis of one's [[Y chromosome]], [[Mitochondrial DNA|mtDNA]] or [[Autosome|autosomal DNA]], has reignited the debate surrounding race. Most of the controversy surrounds the question of how to interpret these new data, and whether conclusions based on existing data are sound. Although the vast majority of researchers endorse the view that continental groups do not constitute different subspecies, and molecular geneticists generally reject the identification of mtDNA and Y chromosomal lineages or allele clusters with "races", some anthropologists have suggested that the marketing of genetic analysis to the general public in the form of "Personalized Genetic Histories" (PGH) is leading to a new social construction of race. See above sections [[Race (classification of human beings)#Molecular lineages, Y chromosomes and mitochondrial DNA|Molecular lineages, Y chromosomes and mitochondrial DNA]] and [[Race (classification of human beings)#How much are genes shared? Clustering analyses and what they tell us|How much are genes shared? Clustering analyses and what they tell us]].
Typically, a consumer of a commercial PGH service sends in a sample of DNA which is analyzed by molecular biologists and is sent a report, of which the following is a sample
:"African DNA Ancestry Report"
{{quotation|The subject's likely [[Haplogroup L2 (mtDNA)|haplogroup L2]] is associated with the so-called Bantu expansion from West and Central sub-Saharan Africa east and south, dated 2,000-4,000 years ago .... Between the 15th and 19th centuries C.E, the Atlantic slave trade resulted in the forced movement of approximately 13 million people from Africa, mainly to the Americas. Only approximately 11 million survived the passage and many more died in the early years of captivity. Many of these slaves were traded to the West African Cape Verde ports of embarkation through Portuguese and Arab middlemen and came from as far south as Angola. Among the African tribal groups, all Bantu-speaking, in which L2 is common are: Hausa, Kanuri, Fulfe, Songhai, Malunjin (Angola), Yoruba, Senegalese, Serer and Wolof.}}
Although no single sentence in such a report is technically wrong, through the combination of these sentences, anthropologists and others have argued, the report is telling a story that connects a haplotype with a language and a group of tribes. This story is generally rejected by research scientists for the simple reason that an individual receives his or her Y chromosome or mtDNA from only one ancestor in every generation; consequently, with every generation one goes back in time, the percentage of ones ancestors it represents halves; if one goes back hundreds (let alone thousands) of years, it represents only a tiny fragment of one's ancestry. As Mark Shriver and Rick Kittles recently remarked,
{{quotation|For many customers of lineage-based tests, there is a lack of understanding that their maternal and paternal lineages do not necessarily represent their entire genetic make-up. For example, an individual might have more than 85% Western European 'genomic' ancestry but still have a West African mtDNA or NRY lineage.}}
Nevertheless, they acknowledge, such stories are increasingly appealing to the general public.<ref>Mark D. Shriver & Rick A. Kittles, "Genetic ancestry and the search for personalized genetic histories" in ''Nature Reviews Genetics'' 5, 611-618 </ref> Thus, in his book ''[[Blood of the Isles]]'' (published in the US and Canada as ''Saxons, Vikings and Celts: The Genetic Roots of Britain and Ireland''), however, [[Bryan Sykes]] discusses how people who have been mtDNA tested by his commercial laboratory and been found to belong to the same haplogroup have parties together because they see this as some sort of "bond", even thought these people may not actually share very much ancestry.
Through these kinds of reports, new advances in molecular genetics are being used to create or confirm stories have about [[Identity (social science)|social identities]]. Although these identities are not racial in the biological sense, they are in the cultural sense in that they link biological and cultural identities. Nadia Abu el-Haj has argued that the significance of gentetic lineages in popular conceptions of race owes to the perception that while genetic lineages, like older notions of race, suggests some idea of biological relatedness, unlike older notions of race they are not directly connected to claims about human behaviour or character. Abu el-Haj has thus argued that "postgenomics does seem to be giving race a new lease on life." Nevertheless, Abu el-Haj argues that in order to understand what it means to think of race in terms of genetic lineages or clusters, one must understand that
{{quotation|Race science was never just about classification. It presupposed a distinctive relationship between "nature" and "culture," understanding the differences in the former to ground and to generate the different kinds of persons ("natural kinds") and the distinctive stages of cultures and civilizations that inhabit the world.}}
Abu el-Haj argues that genomics and the mapping of lineages and clusters liberates "the new racial science from the older one by disentangling ancestry from culture and capacity." As an example, she refers to recent work by Hammer ''et al.'', which aimed to test the claim that present-day Jews are more closely related to one another than to neighbouring non-Jewish populations. Hammer ''et. al'' found that the degree of genetic similarity among Jews shifted depending on the locus investigated, and suggested that this was the result of natural selection acting on particular loci. They therefore focused on the non-recombining Y chromosome to "circumvent some of the complications associated with selection".<ref>Hammer, M.F., A.J. Redd, E.T. Wood, M. R. Bonner, H. Jarjanazi, T. karafet, S. Santachiara-Benerecetti, A. Oppenheimer, M.A. Jobling, T. Jenkins, H. Ostrer, and B. Bonne-Tamir (2000) "Jewish and Middle Eastern Non-Jewish Populations Share a Common pool of Y-Chromosome Biallelic Haplotypes" in ''Proceedings of the National Academy of Sciences'' 97(12): 6769-6774</ref> As another example she points to work by Thomas ''et al.'', who sought to distinguish between the Y chromosomes of Jewish priests (in Judaism, membership in the priesthood is passed on through the father's line) and the Y chromosomes of non-Jews.<ref> Thomas, M. K. Skoprecski, K. Ben-Ami, H. Parfitt, T. Bradman, and D.B. Goldstein (1988) "Oriigins of Old Testament priests" in ''Nature'' 394(6689): 138-140.</ref> Abu el-Haj concluded that this new "race science" calls attention to the importance of "ancestry" (narrowly defined, as it does not include all ancestors) in some religions and in popular culture, and peoples' desire to use science to confirm their claims about ancestry; this "race science," she argues is fundamentally different from older notions of race that were used to explain differences in human behaviour or social status:
{{quotation|As neutral markers, [[junk DNA]] cannot generate cultural, behavioural, or, for that matter, truly biological differences between groups .... mtDNA and Y-chromosome markers relied on in such work are not "traits" or "qualities" in the old racial sense. They do not render some populations more prone to violence, more likely to suffer psychiatric disorders, or for that matter, incapable of being fully integrated - because of their lower evolutionary development - into a European cultural world. Instead, they are "marks," signs of religious beliefs and practices .... it is via biological noncoding genetic evidence that one can demonstrate that history itself is shared, that historical traditions are (or might well be) true."<ref> Nadia Abu el-Haj (2007) Rethinking Genetic Genealogy" in ''American Ethnology'' 34(2): 224-225</ref>}}
On the other hand, there are tests that do not rely on molecular lineages, but rather on correlations between allele frequencies, often when allele frequencies correlate these are called clusters. Clustering analyses are less powerful than lineages because they cannot tell an historical story, they can only estimate the proportion of a person's ancestry from any given large geographical region. These sorts of tests use informative alleles called [[Ancestry-informative marker]] (AIM), which although shared across all human populations vary a great deal in frequency between groups of people living in geographically distant parts of the world. These tests use contemporary people sampled from certain parts of the world as references to determine the likely proportion of ancestry for any given individual. In a recent [[Public Service Broadcasting]] (PBS) programme on the subject of genetic ancestry testing the academic [[Henry Louis Gates]]: "wasn’t thrilled with the results (it turns out that 50 percent of his ancestors are likely European)".<ref name="Frank"/> Charles Rotimi, of Howard University's National Human Genome Center, is one of many who have highlighted the methodological flaws in such research - that "the nature or appearance of genetic clustering (grouping) of people is a function of how populations are sampled, of how criteria for boundaries between clusters are set, and of the level of resolution used" all bias the results - and concluded that people should be very cautious about relating genetic lineages or clusters to their own sense of identity.<ref>Charles Rotimi (2003) "Genetic Ancestry Tracing and the Abridan identity: A Double-Edged Sword?" in ''Developing World Bioethics'' 3(2): 153-154.</ref> (see also above section [[Race (classification of human beings)#How much are genes shared? Clustering analyses and what they tell us|How much are genes shared? Clustering analyses and what they tell us]])
Thus, in analyses that assign individuals to groups it becomes less apparent that self-described racial groups are reliable indicators of ancestry. One cause of the reduced power of the assignment of individuals to groups is [[wiktionary:admixture|admixture]]. For example, self-described African Americans tend to have a mix of West African and European ancestry. Shriver et al. (2003)<ref name="Shriver03" /> found that on average African Americans have ~80% African ancestry. Also, in a survey of college students who self-identified as “white” in a northeastern U.S. university, ~30% of whites had less than 90% European ancestry.<ref>[http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1275602 The Use of Racial, Ethnic, and Ancestral Categories in Human Genetics Research<!-- Bot generated title -->]</ref>
Stephan Palmie has responded to Abu el-Haj's claim that genetic lineages make possible a new, politically, economically, and socially benign notion of race and racial difference by suggesting that efforts to link genetic history and personal identity will inevitably "ground present social arrangements in a time-hallowed past," that is, use biology to explain cultural differences and social inequalities.<ref>Stephan Palmie (2007) "Genomic Moonlighting, Jewish Cyborgs, and Peircian Abduction" in ''American Ethnologist'' 34(2): 249.</ref>
== Political and practical uses ==
=== Racism ===
{{main|Racism|Racial segregation}}
=== Race and intelligence ===
{{main|Race and intelligence}}
Researchers have reported differences in the average [[IQ]] test scores of various ethnic groups. The interpretation, causes, accuracy and reliability of these differences are highly controversial. Some researchers, such as [[Arthur Jensen]], [[Richard Herrnstein]], and [[Richard Lynn]] have argued that such differences are at least partially genetic. Others, for example [[Thomas Sowell]], argue that the differences largely owe to social and economic inequalities. Still others have such as [[Stephen Jay Gould]] and [[Richard Lewontin]] have argued that categories such as "race" and "intelligence" are cultural constructs that render any attempt to explain such differences (whether genetically or sociologically) meaningless.
The [[Flynn effect]] is the rise of average Intelligence Quotient (IQ) test scores, an effect seen in most parts of the world, although at varying rates. Scholars therefore believe that rapid increases in average IQ seen in many places are much too fast to be as a result of changes in brain physiology and more likely as a result of environmental changes. The fact that environment has a significant effect on IQ demolishes the case for the use of IQ data as a source of genetic information.<ref name="race_myth">[http://www.amazon.com/gp/reader/0813533023/ biological theories of race page165]</ref><ref name="race_myth2">[http://www.amazon.com/gp/reader/B000F7113I/ page183]</ref>
=== In biomedicine ===
{{main|Race in biomedicine}}
There is an active debate among biomedical researchers about the meaning and importance of race in their research. The primary impetus for considering race in biomedical research is the possibility of improving the prevention and treatment of [[disease]]s by predicting hard-to-ascertain factors on the basis of more easily ascertained characteristics. Some have argued that in the absence of cheap and widespread genetic tests, racial identification is the best way to predict for certain diseases, such as [[Cystic fibrosis]], [[Lactose intolerance]], [[Tay-Sachs Disease]] and [[sickle cell anemia]], which are genetically linked and more prevalent in some populations than others. The most well-known examples of genetically-determined disorders that vary in incidence among populations would be [[sickle cell disease]], [[thalassaemia]], and [[Tay-Sachs disease]]. [[Image:Sickle cell distribution.jpg|thumb|right|180px|distribution of the sickle cell trait]]
[[Image:Malaria distribution.jpg|thumb|right|180px|distribution of [[Malaria]] ]]
There has been criticism of associating disorders with race. For example, in the United States sickle cell is typically associated with black people, but this trait is also found in people of Mediterranean, Middle Eastern or Indian ancestry.<ref>[http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/sca.shtml sickle cell prevalence]</ref> The sickle cell trait offers some resistance to [[malaria]]. In regions where malaria is present sickle cell has been [[Balancing selection|positively selected]] and consequently the proportion of people with it is greater. Therefore, it has been argued that sickle cell should not be associated with a particular race, but rather with having ancestors who lived in a malaria-prone region. Africans living in areas where there is no malaria, such as the East African highlands, have prevalence of sickle cell as low as parts of Northern Europe.
Another example of the use of race in medicine is the recent [[Food and Drug Administration|U.S. FDA]] approval of [[Isosorbide dinitrate/hydralazine|BiDil]], a medication for congestive heart failure targeted at black people in the United States.<ref>Taylor AL, Ziesche S, Yancy C, Carson P, D'Agostino R Jr, Ferdinand K, Taylor M, Adams K, Sabolinski M, Worcel M, Cohn JN. Combination of isosorbide dinitrate and hydralazine in blacks with heart failure. N Engl J Med 2004;351:2049-57. PMID 15533851.</ref> Several researchers have questioned the scientific basis for arguing the merits of a medication based on race, however. As Stephan Palmie has recently pointed out, black Americans were disproportionately affected by Hurricane Katrina, but for social and not climatological reasons; similarly, certain diseases may disproportionately affect different races, but not for biological reasons. Several researchers have suggested that BiDil was re-designated as a medicine for a race-specific illness because its manufacturer, Nitromed, needed to propose a new use for an existing medication in order to justify an extension of its patent and thus monopoly on the medication,<ref> Duster, Troy (2005) "Race and Reification in Science" in ''Science'' 307(5712): 1050-1051, Fausto-Sterling, Anne (2004) "Refashioning Race: DNA and the Politics of Health" in ''differences'' 15(3):1-37, Jones, Joseph and Alan Goodman (2005) "BiDil and the 'fact' of Genetic Blackness" in ''Anthropology News'' 46(7):26, Kahn, Joseph (2004) "How a Drug Becomes 'Ethnic:' Law, Commerce, and the Production of Racial Categories in Medicine" in ''Yale Journal of Health Policy, Law and Politics'' 4(1):1-46, Kahn, Joseph (2005) "Misreading Race and Genomics after BiDil" in ''Nature Genetics 37(7):655-656, Palmie, Stephan (2007) "Genomics, Divination and 'Racecraft'" in ''American Ethnologist'' 34(2): 205-222).</ref> not for pharmacological reasons.
[[Gene flow]] and intermixture also have an effect on predicting a relationship between race and "race linked disorders". Multiple sclerosis is typically associated with people of European descent and is of low risk to people of African descent. However, due to gene flow between the populations, African Americans have elevated levels of MS relative to Africans.<ref>[http://www.med.harvard.edu/publications/On_The_Brain/Volume05/Number4/MSf.html Multiple Sclerosis. ''The Immune System's Terrible Mistake.''] BY PETER RISKIND, M.D., PH.D.</ref> Notable African Americans affected by MS include [[Richard Pryor]] and [[Montel Williams]]. As populations continue to mix, the role of socially constructed races may diminish in identifying diseases.
=== In law enforcement ===
[[Image:RaceMugshots.jpg|thumb|210px|In the U.S., the [[Federal Bureau of Investigation|FBI]] [[anthropometry|identifies fugitives]] to categories they define as sex, physical features, occupation, nationality, and race. From left to right, the FBI assigns the above individuals to the following races: White, Black, White (Hispanic), Asian. Top row males, bottom row females.<ref>{{cite web |url=http://www.fbi.gov/wanted/topten/fugitives/fugitives.htm |title=FBI - Most Wanted - The FBI's Ten Most Wanted Fugitives}}</ref>]]
In an attempt to provide general descriptions that may facilitate the job of [[law enforcement officer]]s seeking to apprehend suspects, the United States [[Federal Bureau of Investigation|FBI]] employs the term "race" to summarize the general appearance (skin color, hair texture, eye shape, and other such easily noticed characteristics) of individuals whom they are attempting to apprehend. From the perspective of [[Law enforcement agency|law enforcement]] officers, it is generally more important to arrive at a description that will readily suggest the general appearance of an individual than to make a scientifically valid categorization by DNA or other such means. Thus in addition to assigning a wanted individual to a racial category, such a description will include: height, weight, eye color, scars and other distinguishing characteristics, etc. [[Scotland Yard]] use a classification based in the ethnic background of [[British society]]: W1 (White-British), W2 (White-Irish), W9 (Any other white background); M1 (White and black Caribbean), M2 (White and black African), M3 (White and Asian), M9 (Any other mixed background); A1 (Asian-Indian), A2 (Asian-Pakistani), A3 (Asian-Bangladeshi), A9 (Any other Asian background); B1 (Black Caribbean), B2 (Black African), B3 (Any other black background); O1 (Chinese), O9 (Any other). Some of the characteristics that constitute these groupings are biological and some are learned (cultural, linguistic, etc.) traits that are easy to notice.
In many countries, such as [[France]], the state is legally banned from maintaining data based on race, which often makes the police issue wanted notices to the public that include labels like "dark skin complexion", etc. One of the factors that encourages this kind of circuitous wordings is that there is controversy over the actual relationship between crimes, their assigned punishments, and the division of people into the so called "races," leading officials to try to deemphasize the alleged race of suspects. In the United States, the practice of [[racial profiling]] has been ruled to be both [[unconstitutional]] and also to constitute a violation of [[civil rights]]. There is active debate regarding the cause of a marked correlation between the recorded crimes, punishments meted out, and the country's "racially divided" people. Many consider ''de facto'' [[racial profiling]] an example of [[institutional racism]] in law enforcement. The history of misuse of racial categories to adversely impact one or more groups and/or to offer protection and advantage to another has a clear impact on debate of the legitimate use of known phenotypical or genotypical characteristics tied to the presumed race of both victims and perpetrators by the government.
More recent work in racial taxonomy based on DNA cluster analysis (see [[Lewontin's Fallacy]]) has led law enforcement to narrow their search for individuals based on a range of phenotypical characteristics found consistent with DNA evidence.<ref> [http://transobj.workopolis.com/servlet/Content/fasttrack/20050625/DNA25?section=Biotech '''Molecular eyewitness: DNA gets a human face''' ''Controversial crime-scene test smacks of racial profiling, critics say''] CAROLYN ABRAHAM [[June 25]], [[2005]]</ref>
While controversial, DNA analysis has been successful in helping police identify both victims and perpetrators by giving an indication of what phenotypical characteristics to look for and what community the individual may have lived in. For example, in one case phenotypical characteristics suggested that the friends and family of an unidentified victim would be found among the Asian community, but the DNA evidence directed official attention to missing Native Americans, where her true identity was eventually confirmed.<ref>[http://www.usatoday.com/news/nation/2005-08-16-dna_x.htm DNA tests offer clues to suspect's race] By Richard Willing, USA TODAY</ref> In an attempt to avoid potentially misleading associations suggested by the word "race," this classification is called "biogeographical ancestry" (BGA),<ref>[http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PG01&s1=20040229231&OS=20040229231&RS=20040229231 Compositions and methods for inferring ancestry]</ref> but the terms for the BGA categories are similar to those used as for race. The difference is that ancestry-informative DNA markers identify continent-of-ancestry admixture, not ethnic self-identity, and provide a wide range of phenotypical characteristics such that some people in a biogeographical category will not match the stereotypical image of an individual belonging to the corresponding race. To facilitate the work of officials trying to find individuals based on the evidence of their DNA traces, firms providing the genetic analyses also provide photographs showing a full range of phenotypical characteristics of people in each biogeographical group. Of special interest to officials trying to find individuals on the basis of DNA samples that indicate a diverse genetic background is what range of phenotypical characteristics people with that general mixture of genotypical characteristics may display.
Similarly, [[forensic anthropology|forensic anthropologists]] draw on highly heritable morphological features of human remains (e.g. cranial measurements) in order to aid in the identification of the body, including in terms of race. In a recent article anthropologist Norman Sauer asked, "if races don't exist, why are forensic anthropologists so good at identifying them."<ref>Sauer, Norman J. (1992) "Forensic Anthropology and the Concept of Race: If Races Don't Exist, Why are Forensic Anthropologists So Good at Identifying them" in Social Science and Medicine 34(2): 107-111. </ref> Sauer observed that the use of 19th century racial categories is widespread among forensic anthropologists:
*"In many cases there is little doubt that an individual belonged to the Negro, Caucasian, or Mongoloid racial stock."<ref>El-Najjar M. Y. and McWilliams K. R. ''Forensic Anthropology: The Structure, Morphology and Variation of Human Bone and Dentition'', p. 72. Charles C. Thomas, Springfield, 1978.</ref>
*"Thus the forensic anthropologist uses the term race in the very broad sense to differentiate what are commonly known as white, black and yellow racial stocks."<ref>Skinner M. and Lazenby R. A. ''Found Human Remains: A Field Manual for the Recovery of the Recent Human Skeletons'', p. 47. Simon Fraser University, British Columbia, 1983.</ref>
*"In estimating race forensically, we prefer to determine if the skeleton is Negroid, or Non-Negroid. If findings favor Non-Negroid, then further study is necessary to rule out Mongoloid."<ref>Morse D., Duncan J. and Stoutamire J. (Editors) ''Handbook of Forensic Archaeology''. p. 89. Bill’s Book Store, Tallahassee, 1983. </ref>
According to Sauer, "The assessment of these categories is based upon copious amounts of research on the relationship between biological characteristics of the living and their skeletons." Nevertheless, he agrees with other anthropologists that race is not a valid biological taxonomic category, and that races are socially constructed. He argued there is nevertheless a strong relationship between the phenotypic features forensic anthropologists base their identifications on, and popular racial categories. Thus, he argued, forensic anthropologists apply a racial label to human remains because their analysis of physical morphology enables them to predict that when the person was alive, that particular racial label would have been applied to them.<ref>Sauer, Norman J. (1992) "Foren Anthropology and the Concept of Race: If Races Don't Exist, Why are Forensic Anthropologists So Good at Identifying them" in Social Science and Medicine 34(2): 107-111. </ref>
==See also==
{|
||
*[[Breed]]
*[[Black Nationalism]]
*[[Clan]]
*[[Ethnicity]]
*[[Species]]
*[[Political correctness]]
*[[Cultural difference]]
*[[Population genetics]]
*[[Pre-Adamite]]
*[[Multiracial]]
||
*[[Race (historical definitions)]]
*[[Racial stereotypes]]
*[[Race and genetics]]
*[[Race and health]]
*[[Race and intelligence]]
*[[Race (fantasy)]]
*[[Race (U.S. census)]]
*[[Race in biomedicine]]
*[[Race baiting]]
*[[Racial discrimination]]
||
*[[Racial segregation]]
*[[Racial superiority]]
*[[The Race Question]]
*[[The Race of the Future]]
*[[Subspecies]]
*[[White Nationalism]]
*[[Whiteness studies]]
*[[Nationalism]]
*[[Ethnic nationalism]]
*[[List of ethnic groups]]
|}
==Footnotes==
{{reflist|3}}
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== Bibliography ==<!-- GenomeRes14 p1679 from [[Human genetic variation]] [[Race and genetics]] -->
<div class="references-small" style="-moz-column-count:2; column-count:2;">
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</div>
==External links==
{{wikiquote}}
===Official statements and standards===
* [http://www.aaanet.org/stmts/racepp.htm American Anthropological Association's Statement on Race] and [http://www.understandingRACE.org RACE: Are we so different?]a public education program developed by the American Anthropological Association.
* [http://www.physanth.org/positions/race.html American Association of Physical Anthropologists' Statement on Biological Aspects of Race]
* OMB Statistical Directive 15, [http://www.doi.gov/diversity/doc/racedata.htm "Standards for Maintaining, Collecting, and Presenting Federal Data on Race and Ethnicity"], ''Federal Register'', [[30 October]] [[1997]].
*[http://unesdoc.unesco.org/images/0012/001282/128291eo.pdf "The Race Question"], [[UNESCO]], 1950
* [http://quickfacts.census.gov/qfd/meta/long_68184.htm US Census Bureau: Definition of Race]
=== Popular press ===
* [[Richard Dawkins]]: [http://www.prospect-magazine.co.uk/article_details.php?id=6467 Race and creation] (extract from [[The Ancestor's Tale]]: A Pilgrimage to the Dawn of Life) - On race, its usage and a theory of how it evolved. ([http://www.prospect-magazine.co.uk/ Prospect Magazine] October 2004)
* [http://www.medicinemagazine.info/consumer/index.php/articles/5-human-evolution-biology-and-anthropology/7-the-myth-of-race The Myth of Race] On the lack of scientific basis for the concept of human races ([[Medicine Magazine]], 2007).
* [http://www.pbs.org/race Race - The power of an illusion] Online companion to California Newsreel's 3-part documentary about race in society, science, and history.
* [http://raceandgenomics.ssrc.org/ Is Race "Real"?] - forum organized by the [[Social Science Research Council]], includes a [http://raceandgenomics.ssrc.org/Leroi/ March 2005 op-ed article by A.M. Leroi from the ''New York Times''] advocating biological conceptions of race and responses from scholars in a variety of fields. - [http://www.edge.org/3rd_culture/leroi05/leroi05_index.html More from Leori with responses]
* Steven and Hilary Rose, The Guardian, [http://www.politics.guardian.co.uk/life/science/story/0,12996,1455716,00.html "Why we should give up on race"], [[9 April]] [[2005]]
* Times Online, [http://www.timesonline.co.uk/article/0,,8122-1331319,00.html "Gene tests prove that we are all the same under the skin"], [[27 October]] [[2004]].
* Michael J. Bamshad, Steve E. Olson [http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=00055DC8-3BAA-1FA8-BBAA83414B7F0000 "Does Race Exist?"], ''Scientific American'', December 2003
* [http://www.nytimes.com/2002/12/20/health/20GENE.html "Gene Study Identifies 5 Main Human Populations, Linking Them to Geography"], Nicholas Wade, ''NYTimes'', December 2002. Covering
*[http://www.sciam.com/article.cfm?chanID=sa006&articleID=00055DC8-3BAA-1FA8-BBAA83414B7F0000 Scientific American Magazine (December 2003 Issue) Does race exists ?].
* [http://www.upi.com/view.cfm?StoryID=15042002-084051-5356r DNA Study published by United Press International showing how 30% of White Americans have at least one Black ancestor]
* Yehudi O. Webster [http://multiracial.com/site/index.php?option=com_content&task=view&id=213&Itemid=39 Twenty-one Arguments for Abolishing Racial Classification], ''The Abolitionist Examiner'', June 2000
* [http://literature.sdsu.edu/nericcio/textmex.html The Tex(t)-Mex Galleryblog], An updated, online supplement to the University of Texas Press book (2007), [http://www.utexas.edu/utpress/books/nertex.html Tex(t)-Mex]
* [http://timesofindia.indiatimes.com/Opinion/Editorial/Cut_out_the_racism/articleshow/2208634.cms Times of India] - Article about Asian racism
* [http://www.sussex.ac.uk/ir/documents/april_4_2007.pdf South China Morning Post] - Going beyond ‘sorry’
=== Others ===
* [http://www.newsreel.org/guides/race/10things.htm Ten Things Everyone Should Know About Race] by California Newsreel.
* [http://www.understandingRACE.org American Anthropological Association's educational website on race, geared for general public with links for primary school educators and researchers]
*[http://www.southwestern.edu/~greenmue/boas.htm Boas's remarks on race to a general audience]
* Catchpenny mysteries of ancient Egypt, [http://www.catchpenny.org/race.html "What race were the ancient Egyptians?"], Larry Orcutt.
* Judy Skatssoon, [http://www.abc.net.au/science/news/stories/s1153697.htm "New twist on out-of-Africa theory"], ''ABC Science Online'', Wednesday, [[14 July]] [[2004]].
* [http://www.bloodbook.com/world-abo.html Racial & Ethnic Distribution of ABO Blood Types] - bloodbook.com
*[http://www.jonentine.com/reviews/daily_mail_uk.htm Are White Athletes an Endangered Species? And Why is it Taboo to Talk About It?] Discussion of racial differences in athletics
*[http://www.pbs.org/wgbh/nova/first/gill.html "Does Race Exist? A proponent's perspective"] - The author argues that the evidence from forensic anthropology supports the idea of race.
*[http://www.pbs.org/wgbh/nova/first/brace.html "Does Race Exist? An antagonist's perspective"] - The author argues that clinal variation undermines the idea of race.
*[http://www.americanethnography.com/article_sql.php?id=36 "American Ethnography -- The concept of race"] Ashley Montagu's article in American Anthropology from 1962.
*[http://www.americanethnography.com/article_sql.php?id=37 "American Ethnography -- The genetical theory of race, and anthropological method"] Ashley Montagu's article in American Anthropology from 1942.
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[[Category:Race]]
[[Category:Social inequality]]
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[[Category:Concepts (nationalism studies)]]
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[[ca:Raça]]
[[da:Race]]
[[de:Rassentheorien]]
[[es:Raza]]
[[eo:Raso]]
[[eu:Arraza]]
[[fr:Race]]
[[hr:Rasa]]
[[id:Ras manusia]]
[[it:Razza]]
[[he:גזע (אדם)]]
[[lt:Rasė]]
[[nl:Menselijk ras]]
[[ja:人種]]
[[no:Menneskeraser]]
[[nn:menneskerasar]]
[[pl:Rasa]]
[[pt:Raça]]
[[ru:Раса]]
[[sr:Раса]]
[[fi:Ihmisrotu]]
[[sv:Människoraser]]
[[tr:Irk]]
[[uk:Раса]]
[[zh:种族]]