An organ of Wycliffe Bible Translators, the purpose of the SIL has been, interestingly enough, the religious conversion and instruction of native populations, with grammars, dictionaries, etc. being constucted to facilitate the translation of religious texts. Mixtecan, Zapotecan, Chinantecan spoken in Valley and adjoining mountains of Oaxaca Otomian - North of Valley of Mexico and on up. Pochutec is a very early immigrant to Oaxaca. Widespread Features l. Zapotec lacks them, but Chatino and Mixtec have them.
Tones are also in Yucatec and a few other Mayan languages.
In northeastern, northwestern, and central Mexico, p and kw usually contrast. Huastec acquired kw and kw' from non-Mayan sources. Glottalized consonants - Eastern languages for the most part, but also Tequistlatec of the west coast, have glottalized consonants. Languages with glottalized consonants occupy peripheral areas in northeast Mexico, southeast, and Oaxaca. Virtually all MA languages, including Coahuilteco, have vigesimal enumeration , in that 2O is a basic unit and all higher numerals are expressed as multiples of 2O plus a remainder.