GlottochronologyGlottochronology (from Attic Greek γλῶττα tongue, language and χρόνος time) is the part of lexicostatistics which involves comparative linguistics and deals with the chronological relationship between languages. The idea was developed by Morris Swadesh in the 1950s in his article on Salish internal relationships. He developed the idea under two assumptions: there indeed exists a relatively stable basic vocabulary (referred to as Swadesh lists) in all languages of the world; and, any replacements happen in a way analogous to radioactive decay in a constant percentage per time elapsed.
LexicostatisticsLexicostatistics is a method of comparative linguistics that involves comparing the percentage of lexical cognates between languages to determine their relationship. Lexicostatistics is related to the comparative method but does not reconstruct a proto-language. It is to be distinguished from glottochronology, which attempts to use lexicostatistical methods to estimate the length of time since two or more languages diverged from a common earlier proto-language.
Mass comparisonMass comparison is a method developed by Joseph Greenberg to determine the level of genetic relatedness between languages. It is now usually called multilateral comparison. The method is rejected by most linguists , though not all. Some of the top-level relationships Greenberg named are now generally accepted, though they had already been posited by others (e.g. Afro-Asiatic and Niger–Congo). Others are accepted by many though disputed by some prominent specialists (e.g.
TongueThe tongue is a muscular organ in the mouth of a typical tetrapod. It manipulates food for chewing and swallowing as part of the digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste buds housed in numerous lingual papillae. It is sensitive and kept moist by saliva and is richly supplied with nerves and blood vessels. The tongue also serves as a natural means of cleaning the teeth. A major function of the tongue is the enabling of speech in humans and vocalization in other animals.
Comparative methodIn linguistics, the comparative method is a technique for studying the development of languages by performing a feature-by-feature comparison of two or more languages with common descent from a shared ancestor and then extrapolating backwards to infer the properties of that ancestor. The comparative method may be contrasted with the method of internal reconstruction in which the internal development of a single language is inferred by the analysis of features within that language.
Historical linguisticsHistorical linguistics, also termed diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include: to describe and account for observed changes in particular languages to reconstruct the pre-history of languages and to determine their relatedness, grouping them into language families (comparative linguistics) to develop general theories about how and why language changes to describe the history of speech communities to study the history of words, i.
Celtic languagesThe Celtic languages (ˈkɛltᵻk ) are a group of related languages descended from Proto-Celtic. They form a branch of the Indo-European language family. The term "Celtic" was first used to describe this language group by Edward Lhuyd in 1707, following Paul-Yves Pezron, who made the explicit link between the Celts described by classical writers and the Welsh and Breton languages. During the first millennium BC, Celtic languages were spoken across much of Europe and central Anatolia.