Atavism

Atavism

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Atavism is the tendency to revert to ancestral type. In biology, an atavism is an evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

ary throwback, such as traits reappearing which had disappeared generations before. Atavisms can occur in several ways. One way is when gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s for previously existing phenotypical
Phenotype
A phenotype is an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, behavior, and products of behavior...

 features are preserved in DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

, and these become expressed through a mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

 that either knock out the overriding genes for the new traits or make the old traits override the new one. A number of traits can vary as a result of shortening of the fetal development of a trait (neoteny
Neoteny
Neoteny , also called juvenilization , is one of the two ways by which paedomorphism can arise. Paedomorphism is the retention by adults of traits previously seen only in juveniles, and is a subject studied in the field of developmental biology. In neoteny, the physiological development of an...

) or by prolongation of the same. In such a case, a shift in the time a trait is allowed to develop before it is fixed can bring forth an ancestral phenotype.

In the social sciences
Social sciences
Social science is the field of study concerned with society. "Social science" is commonly used as an umbrella term to refer to a plurality of fields outside of the natural sciences usually exclusive of the administrative or managerial sciences...

, atavism is a cultural tendency—for example, people in the modern era reverting to the ways of thinking and acting of a former time. The word atavism is derived from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 atavus. An atavus is a great-great-great-grandfather or, more generally, an ancestor.

Examples


Evolutionarily, traits that have disappeared phenotypically do not necessarily disappear from an organism's DNA. The gene sequence often remains, but is inactive. Mathematically, such an unused gene has a reasonable probability of remaining in the genome in a functional state for around 6 million years, but after 10 million years it is almost certain that the gene will no longer function. As long as the gene remains intact, a fault in the genetic control suppressing the gene can lead to it being expressed again. Sometimes, dormant genes can be induced to be expressed by supplying the stimuli artificially.

Examples observed include:
  • Hind legs on whale
    Whale
    Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...

    s or snake
    Snake
    Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

    s
  • Hind fins on dolphin
    Dolphin
    Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in 17 genera. They vary in size from and , up to and . They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating...

    s
  • Extra toes on horse
    Horse
    The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

    s, as in archaic horses
    Evolution of the horse
    The evolution of the horse pertains to the phylogenetic ancestry of the modern horse from the small dog-sized, forest-dwelling Hyracotherium over geologic time scales...

  • Re-emergence of sexual reproduction
    Sexual reproduction
    Sexual reproduction is the creation of a new organism by combining the genetic material of two organisms. There are two main processes during sexual reproduction; they are: meiosis, involving the halving of the number of chromosomes; and fertilization, involving the fusion of two gametes and the...

     in Hieracium pilosella and Crotoniidae
    Crotoniidae
    Crotoniidae are a family of mites of the Desmonomata group that may be the first animal lineage to have abandoned sexual reproduction and then reevolved it...

  • Teeth in chickens

Examples in humans


Atavisms have been observed in humans as well. Babies have been born with a vestigial tail, called "coccygeal process", "coccygeal projection", and "caudal appendage". It can also be evidenced in humans who possess large teeth, like those of other primates. In addition a case of "Snake Heart" has also been reported in medical literature.
  • Humans with extra nipple
    Nipple
    In its most general form, a nipple is a structure from which a fluid emanates. More specifically, it is the projection on the breasts or udder of a mammal by which breast milk is delivered to a mother's young. In this sense, it is often called a teat, especially when referring to non-humans, and...

    s (Accessory breast
    Accessory breast
    Accessory breasts, also known as polymastia, supernumerary breasts, or mammae erraticae, is the condition of having an additional breast...

    )
  • Humans with large canine teeth
    Canine tooth
    In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...


Atavism in history


During the interval between the acceptance of evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

 and the rise of modern understanding of genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

, atavism was used to account for the reappearance in an individual of a trait after several generations of absence. Such an individual was sometimes called a "throwback". The term is often used in connection with the unexpected reappearance of primitive traits in organism
Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...

s.

The notion of atavism was used frequently by social Darwinists
Social Darwinism
Social Darwinism is a term commonly used for theories of society that emerged in England and the United States in the 1870s, seeking to apply the principles of Darwinian evolution to sociology and politics...

, who claimed that inferior races displayed atavistic traits, and represented more primitive traits than their own race. Both the notion of atavism, and Haeckel's
Ernst Haeckel
The "European War" became known as "The Great War", and it was not until 1920, in the book "The First World War 1914-1918" by Charles à Court Repington, that the term "First World War" was used as the official name for the conflict.-Research:...

 recapitulation theory
Recapitulation theory
The theory of recapitulation, also called the biogenetic law or embryological parallelism—and often expressed as "ontogeny recapitulates phylogeny"—is a disproven hypothesis that in developing from embryo to adult, animals go through stages resembling or representing successive stages...

, are saturated with notions of evolution as progress, as a march towards greater complexity and superior ability.

In addition, the concept of atavism as part of an individualistic explanation of the causes of criminal deviance was popularised by the Italian criminologist Cesare Lombroso
Cesare Lombroso
Cesare Lombroso, born Ezechia Marco Lombroso was an Italian criminologist and founder of the Italian School of Positivist Criminology. Lombroso rejected the established Classical School, which held that crime was a characteristic trait of human nature...

 in the 1870s. He attempted to identify physical characteristics common to criminals and labeled those he found as atavistic, 'throwback' traits that determined 'primitive' criminal behavior. His statistical evidence and the closely related idea of eugenics
Eugenics
Eugenics is the "applied science or the bio-social movement which advocates the use of practices aimed at improving the genetic composition of a population", usually referring to human populations. The origins of the concept of eugenics began with certain interpretations of Mendelian inheritance,...

 have long since been discredited, but the concept that physical traits may affect the likelihood of criminal or unethical behavior in the individual strangely still has some scientific support.

The notion that somehow, atavisms could be made to accumulate by selective breeding
Selective breeding
Selective breeding is the process of breeding plants and animals for particular genetic traits. Typically, strains that are selectively bred are domesticated, and the breeding is sometimes done by a professional breeder. Bred animals are known as breeds, while bred plants are known as varieties,...

, or breeding back
Breeding back
Breeding back can be described as either a natural or a human attempt to assemble or re-assemble the genes of an extinct species, subspecies or domesticated breed, which may still be present in the larger gene pool of the overall species or those of multiple interbreedable species.Breeding back is...

, led to breeds such as the Heck cattle
Heck cattle
Heck Cattle are a hardy breed of domestic cattle. They are the result of an attempt to breed back the aurochs, which became extinct in 1627, from modern aurochs-derived cattle...

. This had been bred from ancient landrace
Landrace
A landrace is a local variety of a domesticated animal or plant species which has developed largely by natural processes, by adaptation to the natural and cultural environment in which it lives. It differs from a formal breed which has been bred deliberately to conform to a particular standard...

s with selected primitive traits, in an attempt of "reviving" the extinct aurochs
Aurochs
The aurochs , the ancestor of domestic cattle, were a type of large wild cattle which inhabited Europe, Asia and North Africa, but is now extinct; it survived in Europe until 1627....

.

Cultural atavism


The term atavism is sometimes also applied in the discussion of culture.
Some social scientists
Sociology
Sociology is the study of society. It is a social science—a term with which it is sometimes synonymous—which uses various methods of empirical investigation and critical analysis to develop a body of knowledge about human social activity...

 describe the return of older, "more primitive" tendencies (e.g. warlike attitudes, "clan
Clan
A clan is a group of people united by actual or perceived kinship and descent. Even if lineage details are unknown, clan members may be organized around a founding member or apical ancestor. The kinship-based bonds may be symbolical, whereby the clan shares a "stipulated" common ancestor that is a...

 identity", anything suggesting the social and political atmosphere of thousands of years ago) as "atavistic". "Resurgent atavism" is a common name for the belief that people in the modern era are beginning to revert to ways of thinking and acting that are throwbacks to a former time. This is especially used by sociologists in reference to violence.

The neo-pagan subculture also uses this same terminology ("atavism" or "resurgent atavism") to describe how modern, Western countries are experiencing both the decline of Christianity
Christianity
Christianity is a monotheistic religion based on the life and teachings of Jesus as presented in canonical gospels and other New Testament writings...

 and the rise of religious movements inspired by the pagan
Paganism
Paganism is a blanket term, typically used to refer to non-Abrahamic, indigenous polytheistic religious traditions....

 religions of centuries past. Some cite the rise of environmentalism
Environmentalism
Environmentalism is a broad philosophy, ideology and social movement regarding concerns for environmental conservation and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the concerns of non-human elements...

, scientific inquiry
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

, and liberalization of society
Social liberalism
Social liberalism is the belief that liberalism should include social justice. It differs from classical liberalism in that it believes the legitimate role of the state includes addressing economic and social issues such as unemployment, health care, and education while simultaneously expanding...

 as contributing to an increasingly secular society
Secularism
Secularism is the principle of separation between government institutions and the persons mandated to represent the State from religious institutions and religious dignitaries...

, one in which religious sentiments are more frequently tied with an appreciation of the physical world rather than set against it. Occasionally, the use of these terms in reference to "alternative" spirituality
Spirituality
Spirituality can refer to an ultimate or an alleged immaterial reality; an inner path enabling a person to discover the essence of his/her being; or the “deepest values and meanings by which people live.” Spiritual practices, including meditation, prayer and contemplation, are intended to develop...

 or in an occult
Occult
The word occult comes from the Latin word occultus , referring to "knowledge of the hidden". In the medical sense it is used to refer to a structure or process that is hidden, e.g...

 context implies the use of violence to assert these changing religious views–for example, in the book Lords of Chaos a rash of church burnings across Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...

 has been described as a part of this trend because many of the perpetrators were self-described "pagans" seeking to overthrow what they deemed to be centuries of religious oppression by Christianity.

Atavism is a key term in Joseph Schumpeter
Joseph Schumpeter
Joseph Alois Schumpeter was an Austrian-Hungarian-American economist and political scientist. He popularized the term "creative destruction" in economics.-Life:...

's explanation of World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 in 20th century liberal
Liberalism
Liberalism is the belief in the importance of liberty and equal rights. Liberals espouse a wide array of views depending on their understanding of these principles, but generally, liberals support ideas such as constitutionalism, liberal democracy, free and fair elections, human rights,...

 Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

. He defends a liberal view of international relations
Liberal international relations theory
Unlike realism where the state is seen as a unitary actor, liberalism allows for plurality in state actors. Thus, preferences will vary from state to state, depending on factors such as culture, economic system or government type...

 that an international society built on commerce will avoid war because of war's destructiveness and comparative cost. His reason for WWI is termed "atavism", in which he claims the vestigial governments in Europe (the German Empire
German Empire
The German Empire refers to Germany during the "Second Reich" period from the unification of Germany and proclamation of Wilhelm I as German Emperor on 18 January 1871, to 1918, when it became a federal republic after defeat in World War I and the abdication of the Emperor, Wilhelm II.The German...

, Russian Empire
Russian Empire
The Russian Empire was a state that existed from 1721 until the Russian Revolution of 1917. It was the successor to the Tsardom of Russia and the predecessor of the Soviet Union...

, Ottoman Empire
Ottoman Empire
The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...

, and Austro-Hungarian Empire) pulled the liberal Europe into war, and that the liberal structure of the continent did not cause it. He used this idea to say that liberalism
Liberalism
Liberalism is the belief in the importance of liberty and equal rights. Liberals espouse a wide array of views depending on their understanding of these principles, but generally, liberals support ideas such as constitutionalism, liberal democracy, free and fair elections, human rights,...

 and commerce would continue to have a soothing effect in international relations, and that war would not arise in nations who are built on commercial ties.

Hunter S. Thompson
Hunter S. Thompson
Hunter Stockton Thompson was an American journalist and author who wrote The Rum Diary , Fear and Loathing in Las Vegas and Fear and Loathing on the Campaign Trail '72 .He is credited as the creator of Gonzo journalism, a style of reporting where reporters involve themselves in the action to...

used the phrase "atavistic endeavor" in many of the pieces he wrote and the phrase is still strongly associated with him.

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