Ancient Switch to Soft Food Gave Us an Overbite—and the Ability to Pronounce ‘F’s And ‘V’s
21st February 2025
Not that there’s anything wrong with that….
Don’t like the F-word? Blame farmers and soft food. When humans switched to processed foods after the spread of agriculture, they put less wear and tear on their teeth. That changed the growth of their jaws, giving adults the overbites normal in children. Within a few thousand years, those slight overbites made it easy for people in farming cultures to fire off sounds like “f” and “v,” opening a world of new words.
The newly favored consonants, known as labiodentals, helped spur the diversification of languages in Europe and Asia at least 4000 years ago; they led to such changes as the replacement of the Proto-Indo-European pat?r to Old English faeder about 1500 years ago, according to linguist and senior author Balthasar Bickel at the University of Zurich in Switzerland. The paper shows “that a cultural shift can change our biology in such a way that it affects our language,” says evolutionary morphologist Noreen Von Cramon-Taubadel of the University at Buffalo, part of the State University of New York system, who was not part of the study.
Postdocs Damián Blasi and Steven Moran in Bickel’s lab set out to test an idea proposed by the late American linguist Charles Hockett. He noted in 1985 that the languages of hunter-gatherers lacked labiodentals, and conjectured that their diet was partly responsible: Chewing gritty, fibrous foods puts force on the growing jaw bone and wears down molars. In response, the lower jaw grows larger, and the molars erupt farther and drift forward on the protruding lower jaw, so that the upper and lower teeth align. That edge-to-edge bite makes it harder to push the upper jaw forward to touch the lower lip, which is required to pronounce labiodentals. But other linguists rejected the idea, and Blasi says he, Moran, and their colleagues “expected to prove Hockett wrong.”