Glottochronology (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.^[1]: 131

The idea was developed by Morris Swadesh in the 1950s in his article on Salish internal relationships.^[2] 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. Using mathematics and statistics, Swadesh developed an equation to determine when languages separated and give an approximate time of when the separation occurred. His methods aimed to aid linguistic anthropologists by giving them a definitive way to determine a separation date between two languages. The formula provides an approximate number of centuries since two languages were supposed to have separated from a singular common ancestor. His methods also purported to provide information on when ancient languages may have existed.^[3]

Despite multiple studies and literature containing the information of glottochronology, it is not widely used today and is surrounded with controversy.^[3] Glottochronology tracks language separation from thousands of years ago but many linguists are skeptical of the concept because it is more of a 'probability' rather than a 'certainty.' On the other hand, some linguists may say that glottochronology is gaining traction because of its relatedness to archaeological dates. Glottochronology is not as accurate as archaeological data, but some linguists still believe that it can provide a solid estimate.^[4]

Over time many different extensions of the Swadesh method evolved; however, Swadesh's original method is so well known that 'glottochronology' is usually associated with him.^{[1]: 133 [5]}

Methodology

Discussion

The concept of language change is old, and its history is reviewed in Hymes (1973) and Wells (1973). In some sense, glottochronology is a reconstruction of history and can often be closely related to archaeology. Many linguistic studies find the success of glottochronology to be found alongside archaeological data.^[4] Glottochronology itself dates back to the mid-20th century.^[6][12][7] An introduction to the subject is given in Embleton (1986)^[13] and in McMahon and McMahon (2005).^[14]

Glottochronology has been controversial ever since, partly because of issues of accuracy but also because of the question of whether its basis is sound (for example, Bergsland 1958; Bergsland and Vogt 1962; Fodor 1961; Chrétien 1962; Guy 1980). The concerns have been addressed by Dobson et al. (1972), Dyen (1973)^[15] and Kruskal, Dyen and Black (1973).^[16] The assumption of a single-word replacement rate can distort the divergence-time estimate when borrowed words are included (Thomason and Kaufman 1988).

An overview of recent arguments can be obtained from the papers of a conference held at the McDonald Institute in 2000.^[17] The presentations vary from "Why linguists don't do dates" to the one by Starostin discussed above. Since its original inception, glottochronology has been rejected by many linguists, mostly Indo-Europeanists of the school of the traditional comparative method. Criticisms have been answered in particular around three points of discussion:

• Criticism levelled against the higher stability of lexemes in Swadesh lists alone (Haarmann 1990) misses the point because a certain amount of losses only enables the computations (Sankoff 1970). The non-homogeneity of word lists often leads to lack of understanding between linguists. Linguists also have difficulties finding a completely unbiased list of basic cultural words. it can take a long time for linguists to find a viable word list which can take several test lists to find a usable list.^[8]
• Traditional glottochronology presumes that language changes at a stable rate.

Thus, in Bergsland & Vogt (1962), the authors make an impressive demonstration, on the basis of actual language data verifiable by extralinguistic sources, that the "rate of change" for Icelandic constituted around 4% per millennium, but for closely connected Riksmal (Literary Norwegian), it would amount to as much as 20% (Swadesh's proposed "constant rate" was supposed to be around 14% per millennium).

That and several other similar examples effectively proved that Swadesh's formula would not work on all available material, which is a serious accusation since evidence that can be used to "calibrate" the meaning of L (language history recorded during prolonged periods of time) is not overwhelmingly large in the first place.

It is highly likely that the chance of replacement is different for every word or feature ("each word has its own history", among hundreds of other sources:^[18]).

That global assumption has been modified and downgraded to single words, even in single languages, in many newer attempts (see below).

There is a lack of understanding of Swadesh's mathematical/statistical methods. Some linguists reject the methods in full because the statistics lead to 'probabilities' when linguists trust 'certainties' more.^[8]

• A serious argument is that language change arises from socio-historical events that are, of course, unforeseeable and, therefore, uncomputable.

New methods developed by Gray & Atkinson are claimed to avoid those issues but are still seen as controversial, primarily since they often produce results that are incompatible with known data and because of additional methodological issues.

Modifications

Somewhere in between the original concept of Swadesh and the rejection of glottochronology in its entirety lies the idea that glottochronology as a formal method of linguistic analysis becomes valid with the help of several important modifications. Thus, inhomogeneities in the replacement rate were dealt with by Van der Merwe (1966)^[8] by splitting the word list into classes each with their own rate, while Dyen, James and Cole (1967)^[19] allowed each meaning to have its own rate. Simultaneous estimation of divergence time and replacement rate was studied by Kruskal, Dyen and Black.^[16]

Brainard (1970) allowed for chance cognation, and drift effects were introduced by Gleason (1959). Sankoff (1973) suggested introducing a borrowing parameter and allowed synonyms.

A combination of the various improvements is given in Sankoff's "Fully Parameterised Lexicostatistics". In 1972, Sankoff in a biological context developed a model of genetic divergence of populations. Embleton (1981) derives a simplified version of that in a linguistic context. She carries out a number of simulations using this which are shown to give good results.

Improvements in statistical methodology related to a completely different branch of science, phylogenetics; the study of changes in DNA over time sparked a recent renewed interest. The new methods are more robust than the earlier ones because they calibrate points on the tree with known historical events and smooth the rates of change across them. As such, they no longer require the assumption of a constant rate of change (Gray & Atkinson 2003).

See also

• Basic English
• Cognate
• Dolgopolsky list
• Historical linguistics
• Indo-European studies
• Leipzig–Jakarta list
• Lexicostatistics
• Mass lexical comparison
• Proto-language
• Quantitative comparative linguistics
• Swadesh list

References

Bibliography

• Arndt, Walter W. (1959). The performance of glottochronology in Germanic. Language, 35, 180–192.
• Bergsland, Knut; & Vogt, Hans. (1962). On the validity of glottochronology. Current Anthropology, 3, 115–153.
• Brainerd, Barron (1970). A Stochastic Process related to Language Change. Journal of Applied Probability 7, 69–78.
• Callaghan, Catherine A. (1991). Utian and the Swadesh list. In J. E. Redden (Ed.), Papers for the American Indian language conference, held at the University of California, Santa Cruz, July and August, 1991 (pp. 218–237). Occasional papers on linguistics (No. 16). Carbondale: Department of Linguistics, Southern Illinois University.
• Campbell, Lyle. (1998). Historical Linguistics; An Introduction [Chapter 6.5]. Edinburgh: Edinburgh University Press. ISBN 0-7486-0775-7.
• Chretien, Douglas (1962). The Mathematical Models of Glottochronology. Language 38, 11–37.
• Crowley, Terry (1997). An introduction to historical linguistics. 3rd ed. Auckland: Oxford Univ. Press. pp. 171–193.
• Dyen, Isidore (1965). "A Lexicostatistical classification of the Austronesian languages." International Journal of American Linguistics, Memoir 19.
• Gray, R.D. & Atkinson, Q.D. (2003): "Language-tree divergence times support the Anatolian theory of Indo-European origin." Nature 426-435-439.
• Gudschinsky, Sarah. (1956). The ABC's of lexicostatistics (glottochronology). Word, 12, 175–210.
• Haarmann, Harald. (1990). "Basic vocabulary and language contacts; the disillusion of glottochronology. In Indogermanische Forschungen 95:7ff.
• Hockett, Charles F. (1958). A course in modern linguistics (Chap. 6). New York: Macmillan.
• Hoijer, Harry. (1956). Lexicostatistics: A critique. Language, 32, 49–60.
• Holm, Hans J. (2003). The Proportionality Trap. Or: What is wrong with lexicostatistical Subgrouping Archived 2019-06-02 at the Wayback Machine.Indogermanische Forschungen, 108, 38–46.
• Holm, Hans J. (2005). Genealogische Verwandtschaft. Kap. 45 in Quantitative Linguistik; ein internationales Handbuch. Herausgegeben von R.Köhler, G. Altmann, R. Piotrowski, Berlin: Walter de Gruyter.
• Holm, Hans J. (2007). The new Arboretum of Indo-European 'Trees'; Can new algorithms reveal the Phylogeny and even Prehistory of IE?. Journal of Quantitative Linguistics 14-2:167–214
• Hymes, Dell H. (1960). Lexicostatistics so far. Current Anthropology, 1 (1), 3–44.
• McWhorter, John. (2001). The power of Babel. New York: Freeman. ISBN 978-0-7167-4473-3.
• Nettle, Daniel. (1999). Linguistic diversity of the Americas can be reconciled with a recent colonization. in PNAS 96(6):3325–9.
• Sankoff, David (1970). "On the Rate of Replacement of Word-Meaning Relationships." Language 46.564–569.
• Sjoberg, Andree; & Sjoberg, Gideon. (1956). Problems in glottochronology. American Anthropologist, 58 (2), 296–308.
• Starostin, Sergei. Methodology Of Long-Range Comparison. 2002. pdf
• Thomason, Sarah Grey, and Kaufman, Terrence. (1988). Language Contact, Creolization, and Genetic Linguistics. Berkeley: University of California Press.
• Tischler, Johann, 1973. Glottochronologie und Lexikostatistik [Innsbrucker Beiträge zur Sprachwissenschaft 11]; Innsbruck.
• Wittmann, Henri (1969). "A lexico-statistic inquiry into the diachrony of Hittite." Indogermanische Forschungen 74.1–10.
• Wittmann, Henri (1973). "The lexicostatistical classification of the French-based Creole languages." Lexicostatistics in genetic linguistics: Proceedings of the Yale conference, April 3–4, 1971, dir. Isidore Dyen, 89–99. La Haye: Mouton.
• Zipf, George K. (1965). The Psychobiology of Language: an Introduction to Dynamic Philology. Cambridge, MA: M.I.T.Press.

External links

• Swadesh list in Wiktionary.
• Discussion with some statistics
• A simplified explanation of the difference between glottochronology and lexicostatistics.
• Queryable experiment: quantification of the genetic proximity between 110 languages - with trees and discussion