Published 07 Jul 2008. Tags: history, language, math, words.
Linguistics + Math + History = Glottochronology. YES.
Glottochronology refers to methods in historical linguistics used to estimate the time at which languages diverged, based on the assumption that the basic (core) vocabulary of a language changes at a constant average rate. This assumption, originally put forward by Morris Swadesh, is based on an analogy with the use of carbon dating for measuring the age of organic materials, in that a “lexical half-life” is estimated. The method estimates the length of time since two or more languages diverged from a common earlier proto-language, by counting the number of words that have been replaced in each language. This then yields an estimated date of origin for those languages.
For example, in an attempt to measure how long Easter Island had been isolated, glottochronologists measured the divergence between the Rapa Nui language (spoken on Easter Island) and the language of the neighboring island of Mangareva and used that difference to estimate the amount of time that must have passed since those two languages had diverged. Neat!