How high up you live affects your spoken language. Caleb Everett, an associate professor in the Anthropology Department at the University of Miami published the results of his research into the correlation between elevation and phonemic ejective consonants in PLoS ONE Journal.
Everett looked at ejective consonants which are voiceless consonants which require a sudden burst of air to produce. The air is then compressed at the back of the throat by closing the glottis. Producing this amount of air in the pharynx is unnatural to people at lower elevations. “Ejectives are produced by creating a pocket of air in the pharynx then compressing it.” Everett explains. “Since air pressure decreases with altitude and it takes less effort to compress less dense air, I speculate that it’s easier to produce these sounds at high altitude.” Everett has a audio file that explains and provides examples of the use of ejectives at higher altitudes.
Most of the world’s population inhabits areas of low lying elevations, with only 10% of the world’s population living in areas about 1500 meters. Most of the world’s high-altitude population is located in six regions: the North American Cordillera; the Andes and the Andean altiplano; the southern African plateau; the plateau of the east African rift and the Ethiopian highlands; the Caucasus range and Javakheti plateau; and the Tibetan plateau and surrounding plateaus.
Everett looked at geographic coordinates and elevations of 567 language locations around the world (there are about 7,000 languages in existence). Of those languages, 92 were determined to have ejective phonemic consonants. Of those 92 languages, 57 (62%) are located in high elevation ‘zones’, which the study defined as major regions greater than 1500 meters in altitude including adjoining land within 200 km those high altitude regions. In contrast, 379 of the 475 languages (80%) without ejectives are located in lower lying altitudes. Of the five high-altitude regions, only the Tibetan plateau did not have ejective consonants in the languages surveyed. The lack of the use of ejectives is due to the Tibetan people breathing at a faster rate than other high altitude populations due to an adaptation to the climate which has resulted in a reduction of the effects of hypoxia.
Read the article:
Everett C (2013) Evidence for Direct Geographic Influences on Linguistic Sounds: The Case of Ejectives. PLoS ONE 8(6): e65275. doi:10.1371/journal.pone.0065275