In linguistics, a genetic unit is defined as the totality of languages that derive from a common - often hypothetical - predecessor language ( original language / proto language / basic language , common language ). Thus, every language family is a (maximum) genetic unit (since all languages of a language family are descended from a proto-language), but also every genetically defined subgroup of a language family (subfamily). The method of choice is the so-called "comparative method".
Every isolated language is also a genetic unit. In the family tree of a language family, the genetic units form all languages that belong to a node ( family tree theory ). Members of a genetic unit are considered to be genetically related languages .
Examples: As a language family, Indo-European is a genetic unit, but its subfamilies Romance , Slavic , Germanic also represent genetic units, as they are traced back to proto-languages ( Latin , Urslavic , Urgermanic ). Within Germanic, the West Germanic languages ( German , Yiddish , Luxembourgish , Pennsylvania , Dutch , Afrikaans , English and Frisian ) form a genetic unit. The group “German, English and French ”, on the other hand, does not form a genetic unit.
The term genetic unit can also be understood to denote the “property” of a language group that represents a genetic unit. Example: "The genetic unit of the X group has been proven beyond doubt."
The kinship of languages within a genetic unit is always greater than that of any language outside this unit. The determination of genetic units within language families is often very difficult methodologically, especially if the family consists of very similar languages (cf. Turkic languages ) or contact phenomena between the languages make the genetic origin indistinct.
As a rule, comparative linguistics for the definition of a genetic unit requires evidence of innovations (innovations, linguistic economy ) that only occur in the languages of the unit to be defined. For example, the so-called Germanic sound shift characterizes the unity of the Germanic languages within Indo-European. Lexico-statistical methods are often used to define genetic units . The use of typological and geographical criteria is common, but in the sense of a strict genetic classification, it is not permitted.
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- Gerhard Jäger: How bioinformatics helps to reconstruct the history of language. University of Tübingen, pp. 1–27
- Johann-Mattis List: Historical aspects of the comparative method Historical aspects of the comparative method. A brief overview, Ulm University, Johann-Mattis List, March 12, 2009, pp. 1–16
- Johann-Mattis List: Linguistic Reconstruction: Theories and Methods. Institute for Language and Information, Heinrich Heine University Düsseldorf, Düsseldorf 2009
- Wolfgang Wildgen: How many methods can contact linguistics cope with? University of Bremen, pp. 1–18