Climate Influences Language Evolution

This is Scientific American 60-Second Science. I'm Christopher Intagliata. Got a minute?
Winter is high time for humidifiers.
Because dry air can irritate your throat.
But a new study finds that arid conditions might have influenced the development of the very languages that some people speak.
"Extensive research on human physiology suggests that really dry air makes it hard for us to use our vocal cords very precisely."
Caleb Everett, an anthropological linguistics professor at the University of Miami.
He and his colleagues recently investigated that dry-throat-phenomenon in regards to complex tonal languages, like Cantonese,
where various combinations of rising and falling tones can actually change the meaning of a word, as opposed to non-tonal languages, like English or Italian.
In the non-tonals, the fundamental meaning is the same, whether I say "word" "word" or "word."
By mapping the distribution of more than 3,700 tonal and non-tonal languages,
Everett and his colleagues found that tonal languages tend to cluster in warm, humid areas.
And they're 10 times less prevalent in dry, subfreezing climes, like Siberia, compared with non-tonal languages.
The study is in the Proceedings of the National Academy of Sciences.
Of course, it's physically possible to speak a tonal language in a cold place.
"Obviously speakers of Cantonese for instance can communicate in Siberia and other dry places."
The big picture, Everett says, is that language evolves in relation to where it's spoken.
"Language does not evolve.
It is not impervious to the effects of environment.
Just as ecologies impact human behavior and the adaptive processes of human cultures in myriad ways, they seem to also influence the ways in which languages develop."
Thanks for the minute, for Scientific American's 60-Second Science. I'm Christopher Intagliata.