Repeat: Velvet Fluff

"[The focus on language studies is often on culture] but our work shows that language is also a biological phenomenon -- you can't fully separate culture and biology."
"If you are raised on softer foods, you don't have the same kind of wear and tear on your bite that your ancestors had, so you keep an overbite." 
“The landscape of sounds that we have is fundamentally affected by the biology of our speech apparatus. It's not just cultural evolution."
"Certain sounds like these ‘f’ sounds are recent, and we can say with fairly good confidence that 20,000 or 100,000 years ago, these sounds just simply didn’t exist."
Balthasar Bickel, linguist, University of Zurich

"I hope our study will trigger a wider discussion on the fact that at least some aspects of language and speech—and I insist, some—need to be treated as we treat other complex human behaviors: laying between biology and culture."
"The probabilities [for making labiodentals accidentally] are relatively low, but given sufficient numbers of trials—and by this, we mean that every utterance you make is a single trial—over generations, that leads to the statistical signal we see. But it's not a deterministic process, right?"
Damián Blasi, researcher, Comparative Linguistics Department, University of Zürich (Switzerland) and research affiliate, Department of Linguistic and Cultural Evolution, Max Planck Institute for the Science of Human History

Still from video: Inside Science

A new study out of the University of Zurich in Switzerland on language and sounds humans make in communication, recently published in the journal Science adds another vital element to the science and history of linguistics and speech, pointing out that the human jaw and how the teeth are arranged in the jaw is as much and perhaps more a determinant of speech as is culture and popular practise over the aeons. The study points out the critical influence of the food eaten by humans on the placement of the jaw and the set of our teeth, enabling certain forms of speech.

By analyzing Stone Age against modern skulls the researchers created simulations demonstrating the manner in which variant jaw placements permit our mouths and vocal chords to produce different sounds. A database of about 2,000 languages representing over a quarter of the languages in use to the present day, was utilized in identifying which sounds were given more and which less frequent use, and where that would happen to be geographically. 

Hunter-gatherer society groups in the recent past are recognized as being far less likely to have used consonants, more familiarly used by early-era farming societies, the study discovered. "Our anatomy actually changed the types of sounds being incorporated into languages", pointed out Noreen von Cramon-Taubadel, evolutionary anthropologist at the University of Buffalo, though not herself involved in this study. 

Early human societies chewed meat; tough because it was raw, which wore on jaws and teeth. Much later societies cultivated crops and eventually cooked foods became a common part of the human diet, requiring far less chewing, on soft food stuffs. Consequently, adult skulls dating from the Stone Age look different than more modern skulls, the older skulls' upper and lower teeth closing shut atop each other. Modern skulls reflect the fact that most people have a degree of overbite; front teeth extending slightly over bottom teeth, with closed mouth. 

Over time, humans' diet of softer food reflected on an evolutionary-resulting jaw with a different configuration and that in turn became enabling for different sounds to be produced since pronunciation was simplified. The "f" and "v" sounds are what linguists describe as "labiodental" sounds, and the modern skull with its modified jaw and upper teeth slightly overlapping bottom teeth made their pronunciation possible.

In their research, the linguists studied 52 languages from the Indo-European language group which included dialects spoken from Iceland to India, charting how the "f" and "v" sounds appeared in various languages over time. The sounds became increasingly more commonly used as societies became agricultural and softer food became accessible, with less emphasis on meat consumption, even in its cooked state. 

"New sounds get introduced into languages, and then are more widely adopted", explained Steven Moran, another linguist at the University of Zurich and co-author of the paper.

The difference between a Paleolithic edge-to-edge bite (left) and a modern overbite/overjet bite (right). (Tímea Bodogán)