  The idea of measuring distance between languages seems to have its roots in
the work of the French explorer Dumont D'Urville (D'Urville 1832). He collected
comparative words lists of various languages during his voyages aboard the
Astrolabe from 1826 to1829 and, in his work about the geographical division of
the Pacific, he proposed a method to measure the degree of relation among
languages. The method used by modern glottochronology, developed by Morris
Swadesh in the 1950s (Swadesh 1952), measures distances from the percentage of
shared cognates, which are words with a common historical origin. Recently, we
proposed a new automated method which uses normalized Levenshtein distance
among words with the same meaning and averages on the words contained in a
list. Another classical problem in glottochronology is the study of the
stability of words corresponding to different meanings. Words, in fact, evolve
because of lexical changes, borrowings and replacement at a rate which is not
the same for all of them. The speed of lexical evolution is different for
different meanings and it is probably related to the frequency of use of the
associated words (Pagel et al. 2007). This problem is tackled here by an
automated methodology only based on normalized Levenshtein distance.
