tl;dr:

Before Spain colonised Mexico in the 15th century, there were an estimated 350 indigenous languages. The finding goes against the view that indigenous minority languages have no economic worth. We then examined data about more than 200,000 bilingual families from Mexican censuses to identify patterns in how parents transmit language to their children. We also found that in rural areas, where 68% of the indigenous people live, those indigenous languages that provide more employment opportunities are also more likely to be passed to the next generation. Most indigenous languages in Mexico are used only at elementary levels in education, and government services are rarely provided in these languages.

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