The well-known Brazilian ethnomathematician Ubiratan D’Ambrosio has suggested an answer to why we should study ethnomathematics [14]:
It may compatibilize cultural forms – we should incorporate ethnomathematics in such a way that they facilitate the acquisition of knowledge, understanding, and the compatibilization of known and current popular practices.
The misseri-calendar was successfully made compatible with the Julian calendar of the Christian world in the twelfth century and further successfully made compatible with the Gregorian calendar in 1739. This tradition was continued in Iceland Almanac [15] in the nineteenth century and it still survives today.
Literature, phrases, and proverbs preserve tradition in the language and culture, and link the present with the past by referring to human experiences, independent of time and space. During periods of rapid change, it is of great value to make the old compatible with the new in order to link generations together.
[14] D’Ambrosio, U. 1985. Socio-cultural bases for mathematics education, p. 70. Unicamp, Campinas.
[15] Almanak fyrir Ísland 2015. Reykjavík: University of Iceland.