Every other Friday, the Outside/In team here at NHPR answers listener questions about the natural world.
“I have heard in the past that various languages across the world were influenced by the way the human voice echoes or reacts with the topography of different regions. Could you explore this topic, and see if there's any truth to that?” asked Jackson, calling from South Florida.
To submit a question to the Outside/In team, you can record it as a voice memo on your smartphone and send it to outsidein@nhpr.org. You can also leave a message on our hotline, 1-844-GO-OTTER. No question is too serious or too silly.
Transcript
This has been lightly edited for clarity.
Justine Paradis: The diversity of human languages across the world is vast. Some languages are tonal, like Mandarin.
Mahjong by RTB45 on freesound.org
Justine Paradis: Some incorporate sounds, like clicks in the language of the San people in South Africa.
Click language San Tribe South Africa, erilee on FreeSound.org
Justine Paradis: Even between closely related languages, speaking a new one can mean literally learning new ways of using your mouth.
Repeat after me, aisselles on Freesound.org: Repeat after me. Le drapeau. Le dra– [laugh]. Peau, peau, peau, peau.
Justine Paradis: Language is embodied, so is it possible that the interaction between our bodies and the landscape we live in plays a role in how languages form? Seán Roberts is a linguist at Cardiff University in Wales, and he thinks it’s possible.
Seán Roberts: There's 7000 languages in the world, which is more than people think… because we're used to thinking about the major world languages. Most languages in the world are spoken by a small number of people in a relatively local place. And actually, their language is probably really adapted to the kinds of things that they care about… and the way that they need to communicate.
Justine Paradis: Researchers have found some correlations between environment and language. Like, the world’s biodiversity hotspots are often the very same places with a lot of linguistic diversity.
Seán Roberts: Yeah, and that's a really interesting question. We're not really sure why that is.
Justine Paradis: The factors behind the evolution of a language are complex. They might include war, contact with other cultures, technology, lifestyle. But does the list include landscape? The answer is, we don’t know yet. The question needs more study. Not that people haven’t tried.
Recently, one of Seán’s colleagues, Caleb Everett, came up with a hypothesis, focusing on the physical structure of our throats. Our vocal folds need moisture to produce sound, especially vowels. So, when it’s dry, our vocal cords don’t work as efficiently.
Seán Roberts: If you've ever had a dry throat and tried to sing, then your voice comes out really creaky. What's happening is that your vocal folds are not behaving properly… and so it's hard to control the pitch of your voice.
Justine Paradis: So, perhaps a drier climate could impact the evolution of a language over time, specifically with tonal languages like Mandarin, which require fine-tuned control of the vocal folds. But linguists are often quite skeptical of claims like this, as Seán and his colleagues experienced firsthand, when they presented the theory at a conference in 2024.
Seán Roberts: In this meeting [laughs], we sort of got bombarded by lots of different objections, criticisms. You know, the scientific process. The linguists came along and said, oh, well, languages are related to each other, so they borrow features from each other. The geographers were like, well, languages next to each other tend to be in the same kind of environment… the people in climate science said, well, the climate has changed over the last 10,000 years, so how do you control for that?
Justine Paradis: After this meeting, Seán and his colleagues responded to the feedback by building a model to crunch huge datasets, and to try to control for all these factors. A lot of work for a seemingly simple question: does living in a dry climate mean a loss in tone?
Seán Roberts: And after all that, the answer was no… There’s no evidence that these things work together.
Justine Paradis: That may sound like a failure, but Seán doesn’t see it that way. It’s just the scientific process. For now, he’s excited to refine the model, and to use it to keep exploring this and other exciting questions.
Seán Roberts: Not just about language, but about human migration and what it means to be a human.