The Tzeltals call themselves Winik atel, which means "working men." This is the largest ethnicity in the state, mostly living southeast of San Cristóbal with the largest number in Amatenango. Today, there are about 500,000 Tzeltal Indians in Chiapas. Tzeltal Mayan, part of the Mayan language family, today is spoken by about 375,000 people making it the fourth-largest language group in Mexico. There are two main dialects; highland (or Oxchuc) and lowland (or Bachajonteco). This language, along with Tzotzil, is from the Tzeltalan subdivision of the Mayan language family. Lexico-statistical studies indicate that these two languages probably became differentiated from one another around 1200 Most children are bilingual in the language and Spanish although many of their grandparents are monolingual Tzeltal speakers.