Researchers of a controversial new study believe that the shift of ancient humans’ diet from tough foods to softer ones helped develop their ability to pronounce “f” and “v” sounds.

Did the development of an overbite really help develop human language?

Overbite Development

The range of sounds in language is believed to have been developed about 300,000 years ago. However, sounds such as “f” and “v” are fairly recent developments that researchers of a new study say might have been brought about by changes in diet.

According to the researchers, early humans used to have an edge-to-edge bite because of their hard diet of roots, tough meats, and berries, but this changed with the development of agricultural practices that allowed them to have softer diets that are not too hard on the teeth. Because of this, the juvenile overbite that typically disappeared by adulthood was retained, and a new class of speech sounds was born.

In the new study, researchers combined data, insights, and methods from different disciplines and hypothesize a correlation between food processing technology with the development of labiodentals, a class of sounds that is made by touching the lower lip with the upper teeth, such as in the letter “f”.

“In Europe, our data suggests that the use of labiodentals has increased dramatically only in the last couple of millennia, correlated with the rise of food processing technology such as industrial milling. The influence of biological conditions on the development of sounds has so far been underestimated,” said Steven Moran, one of the study's first authors.

Language Evolution

Some experts say that the study shows how biological constraints on language can eventually change due to cultural changes. However, not everyone is convinced.

According to other experts, the study does not establish that the soft diet really led to the overbite, or even that the harder diet limited the retraction of the jaw, making it difficult to pronounce the "f" and "v" sounds. Furthermore, they state that the development of the overbite simply meant that the people could produce the “f” and “v” sounds more, but not necessarily that all languages will develop it.

Regardless of the differences between the experts, the study does open up a new conversation that may help shed light on how human language came to be.

The study is published in the journal Science.