Anthropocentrism

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https://en.wikipedia.org/wiki/Anthropocentrism

Anthropocentrism (/ˌænθroʊpoʊˈsɛntrɪzəm/; from Ancient Greek: ἄνθρωπος, ánthrōpos, "human being"; and Ancient Greek: κέντρον, kéntron, "center") is the belief that human beings are the central or most important entity in the universe. The term can be used interchangeably with humanocentrism, and some refer to the concept as human supremacy or human exceptionalism. From an anthropocentric perspective, humankind is seen as separate from nature and superior to it, and other entities (animals, plants, minerals, etc) are viewed as resources for humans to use.

Anthropocentrism interprets or regards the world in terms of human values and experiences. It is considered to be profoundly embedded in many modern human cultures and conscious acts. It is a major concept in the field of environmental ethics and environmental philosophy, where it is often considered to be the root cause of problems created by human action within the ecosphere. However, many proponents of anthropocentrism state that this is not necessarily the case: they argue that a sound long-term view acknowledges that the global environment must be made continually suitable for humans and that the real issue is shallow anthropocentrism.

Environmental philosophy

Anthropocentrism, also known as homocentricism or human supremacism, has been posited by some environmentalists, in such books as Confessions of an Eco-Warrior by Dave Foreman and Green Rage by Christopher Manes, as the underlying (if unstated) reason why humanity dominates and sees the need to "develop" most of the Earth. Anthropocentrism is believed by some to be the central problematic concept in environmental philosophy, where it is used to draw attention claims of a systematic bias in traditional Western attitudes to the non-human world. Val Plumwood has argued that anthropocentrism plays an analogous role in green theory to androcentrism in feminist theory and ethnocentrism in anti-racist theory. Plumwood calls human-centredness "anthrocentrism" to emphasise this parallel.

One of the first extended philosophical essays addressing environmental ethics, John Passmore's Man's Responsibility for Nature has been criticised by defenders of deep ecology because of its anthropocentrism, often claimed to be constitutive of traditional Western moral thought. Indeed, defenders of anthropocentrism concerned with the ecological crisis contend that the maintenance of a healthy, sustainable environment is necessary for human well-being as opposed to for its own sake. According to William Grey, the problem with a "shallow" viewpoint is not that it is human-centred: "What's wrong with shallow views is not their concern about the well-being of humans, but that they do not really consider enough in what that well-being consists. According to this view, we need to develop an enriched, fortified anthropocentric notion of human interest to replace the dominant short-term, sectional and self-regarding conception." In turn, Plumwood in Environmental Culture: The Ecological Crisis of Reason argued that Grey's anthropocentrism is inadequate.

Many devoted environmentalists encompass a somewhat anthropocentric-based philosophical view supporting the fact that they will argue in favor of saving the environment for the sake of human populations. Grey writes: "We should be concerned to promote a rich, diverse, and vibrant biosphere. Human flourishing may certainly be included as a legitimate part of such a flourishing." Such a concern for human flourishing amidst the flourishing of life as a whole, however, is said to be indistinguishable from that of deep ecology and biocentrism, which has been proposed as both an antithesis of anthropocentrism. and as a generalised form of anthropocentrism.

Jewish and Christian traditions

In the 1985 CBC series "A Planet For the Taking", Dr. David Suzuki explored the Old Testament roots of anthropocentrism and how it shaped human views of non-human animals. Some Christian proponents of anthropocentrism base their belief on the Bible, such as the verse 1:26 in the Book of Genesis:

And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.

The use of the word "dominion" in the Genesis has been used to justify an anthropocentric worldview, but recently some have found it controversial, viewing it as possibly a mistranslation from the Hebrew. However an argument can be made that the Bible actually places all the importance on God as creator, and humans as merely another part of creation.

Human rights

Anthropocentrism is the grounding for some naturalistic concepts of human rights. Defenders of anthropocentrism argue that it is the necessary fundamental premise to defend universal human rights, since what matters morally is simply being human. For example, noted philosopher Mortimer J. Adler wrote, "Those who oppose injurious discrimination on the moral ground that all human beings, being equal in their humanity, should be treated equally in all those respects that concern their common humanity, would have no solid basis in fact to support their normative principle." Adler is stating here that denying what is now called human exceptionalism could lead to tyranny, writing that if humans ever came to believe that they do not possess a unique moral status, the intellectual foundation of their liberties collapses: "Why, then, should not groups of superior men be able to justify their enslavement, exploitation, or even genocide of inferior human groups on factual and moral grounds akin to those we now rely on to justify our treatment of the animals we harness as beasts of burden, that we butcher for food and clothing, or that we destroy as disease-bearing pests or as dangerous predators?".

Author and anthropocentrism defender Wesley J. Smith from the Discovery Institute has written that human exceptionalism is what gives rise to human duties to each other, the natural world, and to treat animals humanely. Writing in A Rat is a Pig is a Dog is a Boy, a critique of animal rights ideology, "Because we are unquestionably a unique species—the only species capable of even contemplating ethical issues and assuming responsibilities—we uniquely are capable of apprehending the difference between right and wrong, good and evil, proper and improper conduct toward animals. Or to put it more succinctly, if being human isn't what requires us to treat animals humanely, what in the world does?".

Animal rights

Anthropocentrism has been criticised by animal rights and welfare advocates, who contend that the belief that humans are more important than other animals is false and that like humans, non-human animals have intrinsic value. One of the earliest of these critics was the zoologist and philosopher J. Howard Moore, who in The Universal Kinship (1906) argued that Charles Darwin's On the Origin of Species (1859) "sealed the doom of anthropocentricism [sic]" and that:

The supposed psychical gulf between human and non-human beings has no more existence, outside the flamboyant imagination of man, than has the once-supposed physical gulf. It is pure fiction. The supposition is a relic of the rapidly dwindling vanity of anthropocentricism [sic], and is perpetuated from age to age by human selfishness and conceit. It has no foundation either in science or in common-sense. Man strives to lessen his guilt by the laudation of himself and the disparagement and degradation of his victims.

Philosophers such as Peter Singer and David Pearce have argued against anthropocentric ethics, instead advocating for antispeciesist or sentientist ethics, which rather than giving more value to humans based on their species membership, assert that "other things being equal, equally strong interests should count equally." This utilitarian principle is based on the dictum "everybody to count for one, nobody for more than one" attributed to Jeremy Bentham by John Stuart Mill in Utilitarianism (1876).

Cognitive psychology

In cognitive psychology, the term anthropocentric thinking has been defined as "the tendency to reason about unfamiliar biological species or processes by analogy to humans." Reasoning by analogy is an attractive thinking strategy, and it can be tempting to apply one's own experience of being human to other biological systems. For example, because death is commonly felt to be undesirable, it may be tempting to form the misconception that death at a cellular level or elsewhere in nature is similarly undesirable (whereas in reality programmed cell death is an essential physiological phenomenon, and ecosystems also rely on death). Conversely, anthropocentric thinking can also lead people to underattribute human characteristics to other organisms. For instance, it may be tempting to wrongly assume that an animal that is very different from humans, such as an insect, will not share particular biological characteristics, such as reproduction or blood circulation.

Anthropocentric thinking has predominantly been studied in young children (mostly up to the age of 10) by developmental psychologists interested in its relevance to biology education. Children as young as 6 have been found to attribute human characteristics to species unfamiliar to them (in Japan), such as rabbits, grasshoppers or tulips. Although relatively little is known about its persistence at a later age, evidence exists that this pattern of human exceptionalist thinking can continue through young adulthood at least, even among students who have been increasingly educated in biology.

The notion that anthropocentric thinking is an innate human characteristic has been challenged by study of American children raised in urban environments, among whom it appears to emerge between the ages of 3 and 5 years as an acquired perspective. Children's recourse to anthropocentric thinking seems to vary with their experience of nature, and cultural assumptions about the place of humans in the natural world. For example, whereas young children who kept goldfish were found to think of frogs as being more goldfish-like, other children tended to think of frogs in terms of humans. More generally, children raised in rural environments appear to use anthropocentric thinking less than their urban counterparts because of their greater familiarity with different species of animals and plants. Studies involving children from some of the indigenous peoples of the Americas have found little use of anthropocentric thinking. Study of children among the Wichí people in South America showed a tendency to think of living organisms in terms of their perceived taxonomic similarities, ecological considerations, and animistic traditions, resulting in a much less anthropocentric view of the natural world than is experienced by many children in Western societies.

In popular culture

In fiction from all eras and societies, there is fiction treating as normal the actions of humans to ride, eat, milk, and otherwise treat animals as separate species. There are occasional exceptions, such as talking animals, but they are generally treated as exceptions, as aberrations to the rule distinguishing people from animals.

In science fiction, humanocentrism is the idea that humans, as both beings and as a species, are the superior sentients. Essentially the equivalent of racial supremacy on a galactic scale, it entails intolerant discrimination against sentient non-humans, much like race supremacists discriminate against those not of their race. A prime example of this concept is utilized as a story element for the Mass Effect series. After humanity's first contact results in a brief war, many humans in the series develop suspicious or even hostile attitudes towards the game's various alien races. By the time of the first game, which takes place several decades after the war, many humans still retain such sentiments in addition to forming 'pro-human' organizations.

This idea is countered by anti-humanism. At times, this ideal also includes fear of and superiority over strong AIs and cyborgs, downplaying the ideas of integration, cybernetic revolts, machine rule and Tilden's Laws of Robotics.

Mark Twain mocked the belief in human supremacy in Letters from the Earth (written c. 1909, published 1962).

The Planet of the Apes franchise focuses on the analogy of apes becoming the dominant species in society and the fall of humans (see also human extinction). In the 1968 film, Taylor, a human states "take your stinking paws off me, you damn dirty ape!". In the 2001 film, this is contrasted with Attar (a gorilla)'s quote "take your stinking hands off me, you damn dirty human!". This links in with allusions that in becoming the dominant species apes are becoming more like humans (anthropomorphism). In the film Battle for the Planet of the Apes, Virgil, an orangutan states "ape has never killed ape, let alone an ape child. Aldo has killed an ape child. The branch did not break. It was cut with a sword." in reference to planned murder; a stereotypical human concept. Additionally, in Dawn of the Planet of the Apes, Caesar states "I always think...ape better than human. I see now...how much like them we are".

In George Orwell's novel Animal Farm, this theme of anthropocentrism is also present. Whereas originally the animals planned for liberation from humans and animal equality, as evident from the "seven commandments" such as "whatever goes upon two legs is an enemy.", "Whatever goes upon four legs, or has wings, is a friend", "All animals are equal."; the pigs would later abridge the commandments with statements such as "All animals are equal, but some animals are more equal than others." and "Four legs good, two legs better."

The 2012 documentary The Superior Human? systematically analyzes anthropocentrism and concludes that value is fundamentally an opinion, and since life forms naturally value their own traits, most humans are misled to believe that they are actually more valuable than other species. This natural bias, according to the film, combined with a received sense of comfort and an excuse for exploitation of non-humans cause anthropocentrism to remain in society.

Supremacism

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Supremacism

Supremacism is the belief that a certain group of people is superior to all others. The supposed superior people can be defined by age, gender, race, ethnicity, religion, sexual orientation, language, social class, ideology, nation, or culture, or belong to any other part of a particular population.

Sexual

Some feminist theorists have argued that in patriarchy, a standard of male supremacism is enforced through a variety of cultural, political, and interpersonal strategies. Since the 19th century there have been a number of feminist movements opposed to male supremacism, usually aimed at achieving equal legal rights and protections for women in all cultural, political and interpersonal relations.

Racial

Further information: White supremacy, Arab supremacy, Black supremacy, Eurocentrism, Sinocentrism, Han nationalism, Indocentrism, Nazi racial theories, Racism, Institutional racism, Scientific racism, and Racial segregation

Centuries of European colonialism in the Americas, Africa, Australia, Oceania, and Asia were justified by white supremacist attitudes. During the 19th century, the phrase "The White Man's Burden", referring to the thought that whites have the obligation to make the societies of the other peoples more 'civilized', was widely used to justify imperialist policy as a noble enterprise. Thomas Carlyle, known for his historical account of the French Revolution, The French Revolution: A History, which inspired Charles Dickens' novel A Tale of Two Cities, argued that European supremacist policies were justified on the grounds that they provided the greatest benefit to "inferior" native peoples. However, even at the time of its publication in 1849, Carlyle's main work on the subject, the Occasional Discourse on the Negro Question, was received poorly by his contemporaries.

Before the outbreak of the American Civil War, the Confederate States of America was founded with a constitution that contained clauses which restricted the government's ability to limit or interfere with the institution of "negro" slavery. In the Cornerstone Speech, Confederate vice president Alexander Stephens declared that one of the Confederacy's foundational tenets was white supremacy over black slaves. Following the war, a secret society, the Ku Klux Klan, was formed in the South. Its purpose was to "restore" white supremacy after the Reconstruction period, even though there still was white, Protestant supremacy in the United States, at the time. The group preached supremacy over all other races, as well as supremacy over Jews, Catholics, and other minorities.

According to William Nichols, religious antisemitism can be distinguished from modern antisemitism which is based on racial or ethnic grounds. "The dividing line was the possibility of effective conversion ... a Jew ceased to be a Jew upon baptism." However, with racial antisemitism, "Now the assimilated Jew was still a Jew, even after baptism ... . From the Enlightenment onward, it is no longer possible to draw clear lines of distinction between religious and racial forms of hostility towards Jews... Once Jews have been emancipated and secular thinking makes its appearance, without leaving behind the old Christian hostility towards Jews, the new term antisemitism becomes almost unavoidable, even before explicitly racist doctrines appear."

One of the first typologies which was used to classify various human races was invented by Georges Vacher de Lapouge (1854–1936), a theoretician of eugenics, who published in 1899 L'Aryen et son rôle social (1899 – "The Aryan and his social role"). In this book, he classifies humanity into various, hierarchized races, spanning from the "Aryan white race, dolichocephalic", to the "brachycephalic", "mediocre and inert" race, best represented by Southern European, Catholic peasants". Between these, Vacher de Lapouge identified the "Homo europaeus" (Teutonic, Protestant, etc.), the "Homo alpinus" (Auvergnat, Turkish, etc.), and finally the "Homo mediterraneus" (Neapolitan, Andalus, etc.) Jews were brachycephalic like the Aryans, according to Lapouge; but exactly for this reason he considered them dangerous; they were the only group, he thought, which was threatening to displace the Aryan aristocracy. Vacher de Lapouge became one of the leading inspirations of Nazi antisemitism and Nazi racist ideology.

The Anti-Defamation League (ADL) and Southern Poverty Law Center condemn writings about "Jewish Supremacism" by Holocaust-denier, former Grand Wizard of the KKK, and conspiracy theorist David Duke as antisemitic – in particular, his book Jewish Supremacism: My Awakening to the Jewish Question. Kevin B. MacDonald, known for his theory of Judaism as a "group evolutionary strategy", has also been accused by the ADL and his own university psychology department of being "antisemitic" and white supremacist in his writings on the subject.

Cornel West, an African-American philosopher, writes that black supremacist religious views arose in America as part of black Muslim theology in response to white supremacism.

In Africa, black Southern Sudanese allege that they are subjected to a racist form of Arab supremacy, which they equate with the historic white supremacism of South African apartheid. The alleged genocide and ethnic cleansing in the ongoing War in Darfur has been described as an example of Arab racism. For example, in their analysis of the sources of the conflict, Julie Flint and Alex de Waal say that Colonel Gaddafi, the leader of Libya, sponsored "Arab supremacism" across the Sahara during the 1970s. Gaddafi supported the "Islamic Legion" and the Sudanese opposition "National Front, including the Muslim Brothers and the Ansar, the Umma Party's military wing." Gaddafi tried to use such forces to annex Chad from 1979-81. Gaddafi supported the Sudanese government's war in the South during the early 1980s, and in return he was allowed to use the Darfur region as a "back door to Chad". As a result, the first signs of an "Arab racist political platform" appeared in Darfur in the early 1980s.

In Asia, ancient Indians considered all foreigners barbarians. The Muslim scholar Al-Biruni wrote that the Indians called foreigners impure. A few centuries later, Dubois observes that "Hindus look upon Europeans as barbarians totally ignorant of all principles of honour and good breeding... In the eyes of a Hindu, a Pariah (outcaste) and a European are on the same level." The Chinese viewed the Europeans as repulsive, ghost-like creatures, and even as devils. Chinese writers also referred to the Europeans as barbarians.

Nazi Germany

From 1933 to 1945, Nazi Germany, under the rule of Adolf Hitler, promoted the idea of a superior, Aryan Herrenvolk, or master race. The state's propaganda advocated the belief that Germanic peoples, whom they called "Aryans", were a master race or a Herrenvolk whose members were superior to the Jews, Slavs, and Romani people, so-called "gypsies". Arthur de Gobineau, a French racial theorist and aristocrat, blamed the fall of the ancien régime in France on racial intermixing, which he believed had destroyed the purity of the Nordic race. Gobineau's theories, which attracted a large and strong following in Germany, emphasized the existence of an irreconcilable polarity between Aryan and Jewish cultures.

Religious

Christian

Academics Carol Lansing and Edward D. English argue that Christian supremacism was a motivation for the Crusades in the Holy Land, as well as crusades against Muslims and pagans throughout Europe. The blood libel is a widespread European conspiracy theory which led to centuries of pogroms and massacres of European Jewish minorities because it alleged that Jews required the pure blood of a Christian child in order to make matzah for Passover; Thomas of Cantimpré writes of the blood curse which the Jews put upon themselves and all of their generations at the court of Pontius Pilate where Jesus was handed a death sentence: "A very learned Jew, who in our day has been converted to the (Christian) faith, informs us that one enjoying the reputation of a prophet among them, toward the close of his life, made the following prediction: 'Be assured that relief from this secret ailment, to which you are exposed, can only be obtained through Christian blood ("solo sanguine Christiano")." The Atlantic slave trade has also been partially attributed to Christian supremacism. The Ku Klux Klan has been described as a white supremacist Christian organization, as are many other white supremacist groups, such as the Posse Comitatus and the Christian Identity and Positive Christianity movements.

Islamic

Academics Khaled Abou El Fadl, Ian Lague, and Joshua Cone note that, while the Qur'an and other Islamic documents express tolerant, protective beliefs, which have been misused, misquoted, and misinterpreted by both Islamic extremists and Islamophobes, there have also been instances of Muslim or Islamic supremacism. Examples of how supremacists have interpreted Islam include the Muslim participation in the African slave trade, the early-20th-century pan-Islamism promoted by Abdul Hamid II, the jizya and rules of marriage in Muslim countries being imposed on non-Muslims, the majority Muslim interpretations of the rules of pluralism in Malaysia, and "defensive" supremacism practiced by some Muslim immigrants in Europe. According to scholar Bernard Lewis, Classical Islamic jurisprudence imposes an open-ended duty on Muslims to expand Muslim rule and Islamic law to all non-Muslims throughout the world.

Despite being comparatively more tolerant in the past than Christian Europe, North Africa has witnessed numerous incidents of massacres and ethnic cleansing of Jews and Christians, especially in Morocco, Libya and Algeria where eventually Jews were forced to live in ghettos. Decrees ordering the destruction of synagogues were enacted during the Middle Ages in Egypt, Syria, Iraq and Yemen. At certain times in Yemen, Morocco and Baghdad, Jews were forced to convert to Islam or face death. While there were antisemitic incidents before the 20th century, antisemitism increased dramatically as a result of the Arab–Israeli conflict. After the 1948 Arab–Israeli War, the Palestinian exodus, the creation of the state of Israel and Israeli victories during the wars of 1956 and 1967 were a severe humiliation to Israel's opponents—primarily Egypt, Syria and Iraq. However, by the mid-1970s the vast majority of Jews had left Muslim-majority countries, moving primarily to Israel, France and the United States. The reasons for the exodus are varied and disputed.

Jewish

Ilan Pappé, an expatriate Israeli historian, writes that the First Aliyah to Israel "established a society based on Jewish supremacy". Joseph Massad, a professor of Arab studies, holds that "Jewish supremacism" has always been a "dominating principle" in religious and secular Zionism. Zionism was established with the political goal of creating a sovereign Jewish state where Jews could be the majority, rather than the minority which they were in all nations of the world at that time. Theodor Herzl, the ideological father of Zionism, considered antisemitism to be an eternal feature of all societies in which Jews lived as minorities, and as a result, he believed that only a separation could allow Jews to escape eternal persecution. "Let them give us sovereignty over a piece of the Earth's surface, just sufficient for the needs of our people, then we will do the rest!"

Since the 1990s, Orthodox Jewish rabbis from Israel, most notably those affiliated to Chabad-Lubavitch and religious Zionist organizations, including The Temple Institute, have set up a modern Noahide movement to proselytize among non-Jews (usually referred to as "Gentiles" or goyim). These Noahide organizations, led by religious Zionist and Orthodox rabbis, are aimed at non-Jews in order to proselytize among them and commit them to follow the Noahide laws. However, these religious Zionist and Orthodox rabbis that guide the modern Noahide movement, who are often affiliated with the Third Temple movement, expound a racist and supremacist ideology which consists in the belief that the Jewish people are God's chosen nation and racially superior to non-Jews, and mentor Noahides because they believe that the Messianic era will begin with the rebuilding of the Third Temple on the Temple Mount in Jerusalem to re-institute the Jewish priesthood along with the practice of ritual sacrifices, and the establishment of a Jewish theocracy in Israel, supported by communities of Noahides.

David Novak, professor of Jewish theology and ethics at the University of Toronto, has denounced the modern Noahide movement by stating that "If Jews are telling Gentiles what to do, it’s a form of imperialism".

Genetic distance

From Wikipedia, the free encyclopedia

 

 

Genetic distance map by Cavalli-Sforza et al. (1994) 

Genetic distance is a measure of the genetic divergence between species or between populations within a species, whether the distance measures time from common ancestor or degree of differentiation. Populations with many similar alleles have small genetic distances. This indicates that they are closely related and have a recent common ancestor.

Genetic distance is useful for reconstructing the history of populations, such as the multiple human expansions out of Africa. It is also used for understanding the origin of biodiversity. For example, the genetic distances between different breeds of domesticated animals are often investigated in order to determine which breeds should be protected to maintain genetic diversity.

Biological foundation

In the genome of an organism, each gene is located at a specific place called the locus for that gene. Allelic variations at these loci cause phenotypic variation within species (e.g. hair colour, eye colour). However, most alleles do not have an observable impact on the phenotype. Within a population new alleles generated by mutation either die out or spread throughout the population. When a population is split into different isolated populations (by either geographical or ecological factors), mutations that occur after the split will be present only in the isolated population. Random fluctuation of allele frequencies also produces genetic differentiation between populations. This process is known as genetic drift. By examining the differences between allele frequencies between the populations and computing genetic distance, we can estimate how long ago the two populations were separated.

Measures

Although it is simple to define genetic distance as a measure of genetic divergence, there are several different statistical measures that have been proposed. This has happened because different authors considered different evolutionary models. The most commonly used are Nei's genetic distance, Cavalli-Sforza and Edwards measure, and Reynolds, Weir and Cockerham's genetic distance, listed below.

In all the formulae in this section, ${\displaystyle X}$ and ${\displaystyle Y}$ represent two different populations for which ${\displaystyle L}$ loci have been studied. Let ${\displaystyle X_{u}}$ represent the ${\displaystyle u}$^th allele frequency at the ${\displaystyle l}$^th locus.

Nei's standard genetic distance

In 1972, Masatoshi Nei published what came to be known as Nei's standard genetic distance. This distance has the nice property that if the rate of genetic change (amino acid substitution) is constant per year or generation then Nei's standard genetic distance (D) increases in proportion to divergence time. This measure assumes that genetic differences are caused by mutation and genetic drift.

${\displaystyle D=-\ln {\frac {\sum \limits _{\ell }\sum \limits _{u}X_{u}Y_{u}}{\sqrt {\left(\sum \limits _{u}X_{u}^{2}\right)\left(\sum \limits _{u}Y_{u}^{2}\right)}}}}$

This distance can also be expressed in terms of the arithmetic mean of gene identity. Let ${\displaystyle j_{X}}$ be the probability for the two members of population ${\displaystyle X}$ having the same allele at a particular locus and ${\displaystyle j_{Y}}$ be the corresponding probability in population ${\displaystyle Y}$. Also, let ${\displaystyle j_{XY}}$ be the probability for a member of ${\displaystyle X}$ and a member of ${\displaystyle Y}$ having the same allele. Now let ${\displaystyle J_{X}}$, ${\displaystyle J_{Y}}$ and ${\displaystyle J_{XY}}$ represent the arithmetic mean of ${\displaystyle j_{X}}$, ${\displaystyle j_{Y}}$ and ${\displaystyle j_{XY}}$ over all loci, respectively. In other words,

${\displaystyle J_{X}=\sum _{u}{\frac {{X_{u}}^{2}}{L}}}$

${\displaystyle J_{Y}=\sum _{u}{\frac {{Y_{u}}^{2}}{L}}}$

${\displaystyle J_{XY}=\sum _{\ell }\sum _{u}{\frac {X_{u}Y_{u}}{L}}}$

where ${\displaystyle L}$ is the total number of loci examined.

Nei's standard distance can then be written as

${\displaystyle D=-\ln {\frac {J_{XY}}{\sqrt {J_{X}J_{Y}}}}}$

Cavalli-Sforza chord distance

In 1967 Luigi Luca Cavalli-Sforza and A. W. F. Edwards published this measure. It assumes that genetic differences arise due to genetic drift only. One major advantage of this measure is that the populations are represented in a hypersphere, the scale of which is one unit per gene substitution. The chord distance in the hyperdimensional sphere is given by

${\displaystyle D_{\text{CH}}={\frac {2}{\pi }}{\sqrt {2\left(1-\sum _{\ell }\sum _{u}{\sqrt {X_{u}Y_{u}}}\right)}}}$

Some authors drop the factor ${\displaystyle {\frac {2}{\pi }}}$ to simplify the formula at the cost of losing the property that the scale is one unit per gene substitution.

Reynolds, Weir, and Cockerham's genetic distance

In 1983, this measure was published by John Reynolds, Bruce Weir and C. Clark Cockerham. This measure assumes that genetic differentiation occurs only by genetic drift without mutations. It estimates the coancestry coefficient ${\displaystyle \Theta }$ which provides a measure of the genetic divergence by:

${\displaystyle \Theta _{w}={\sqrt {\frac {\sum \limits _{\ell }\sum \limits _{u}(X_{u}-Y_{u})^{2}}{2\sum \limits _{\ell }\left(1-\sum \limits _{u}X_{u}Y_{u}\right)}}}}$

Other measures

Many other measures of genetic distance have been proposed with varying success.

Nei's D_A distance 1983

This distance assumes that genetic differences arise due to mutation and genetic drift, but this distance measure is known to give more reliable population trees than other distances particularly for microsatellite DNA data.

${\displaystyle D_{A}=1-\sum _{\ell }\sum _{u}{\sqrt {X_{u}Y_{u}}}/{L}}$

Euclidean distance

Euclidean genetic distance between 51 worldwide human populations, calculated using 289,160 SNPs. Dark red is the most similar pair and dark blue is the most distant pair.

${\displaystyle D_{EU}={\sqrt {\sum _{u}(X_{u}-Y_{u})^{2}}}}$

Goldstein distance 1995

It was specifically developed for microsatellite markers and is based on the stepwise-mutation model (SMM). ${\displaystyle \mu _{X}}$ and ${\displaystyle \mu _{Y}}$ are the means of the allele sizes in population X and Y.

${\displaystyle (\delta \mu )^{2}=\sum _{\ell }{\frac {(\mu _{X}-\mu _{Y})^{2}}{L}}}$

Nei's minimum genetic distance 1973

This measure assumes that genetic differences arise due to mutation and genetic drift.

${\displaystyle D_{m}={\frac {J_{X}+J_{Y}}{2}}-J_{XY}}$

Roger's distance 1972

${\displaystyle D_{R}={\frac {1}{L}}{\sqrt {\frac {\sum \limits _{u}(X_{u}-Y_{u})^{2}}{2}}}}$

Fixation index

A commonly used measure of genetic distance is the fixation index (F_ST) which varies between 0 and 1. A value of 0 indicates that two populations are genetically identical (minimal or no genetic diversity between the two populations) whereas a value of 1 indicates that two populations are genetically different (maximum genetic diversity between the two populations). No mutation is assumed. Large populations between which there is much migration, for example, tend to be little differentiated whereas small populations between which there is little migration tend to be greatly differentiated. F_ST is a convenient measure of this differentiation, and as a result F_ST and related statistics are among the most widely used descriptive statistics in population and evolutionary genetics. But F_ST is more than a descriptive statistic and measure of genetic differentiation. F_ST is directly related to the Variance in allele frequency among populations and conversely to the degree of resemblance among individuals within populations. If F_ST is small, it means that allele frequencies within each population are very similar; if it is large, it means that allele frequencies are very different.

Software

• PHYLIP uses GENDIST
  • Nei's standard genetic distance 1972
  • Cavalli-Sforza and Edwards 1967
  • Reynolds, Weir, and Cockerham's 1983
• TFPGA
  • Nei's standard genetic distance (original and unbiased)
  • Nei's minimum genetic distance (original and unbiased)
  • Wright's (1978) modification of Roger's (1972) distance
  • Reynolds, Weir, and Cockerham's 1983
• GDA
• POPGENE
• POPTREE2 Takezaki, Nei, and Tamura (2010, 2014)
  • Commonly used genetic distances and gene diversity analysis
• DISPAN
  • Nei's standard genetic distance 1972
  • Nei's D_A distance between populations 1983