Speech may come with its own version of terroir—like the rounded, vowel-rich Hawaiian language or the clipped, consonant-heavy speech of the Republic of Georgia. Much like terroir, these differences might have risen from variations in the landscape from where they originated, according to new research presented last week at the Acoustical Society of America Meeting.

The researchers examined over 600 languages for their structure, including usage of consonants, vowels, and syllables and correlated these factors with climate and landscape features like precipitation and ruggedness, Zoë Schlanger reports for Newsweek. They omitted data from languages where speakers have spread beyond a single region and thus complicate the picture—such as English, Mandarin Chinese and Spanish.

Based on this analysis, the researchers suggest that high frequencies like consonants are interrupted by foliage and higher temperatures. So tree-covered areas tend to foster languages with fewer consonants and more simple syllables. Similarly, consonants spoken in windy or mountainous regions are often lost in the noise.

These warm, foliage-dense rainforests likely clipped words with multiple consonants jammed together. "Where a simple, steady vowel sound like "e" or "a" can cut through thick foliage or the cacophony of wildlife, these consonant-heavy sounds tend to get scrambled," Angus Chen writes for NPR.

Altogether, climatic and ecological factors can explain about one-quarter of the variation in how consonant-rich a language is, reports Emily Underwood for Science.

Yet other factors could muddy the picture, linguist Tecumseh Fitch of the University of Vienna in Austria tells Chen. People who live close to each other tend to have similar, related languages regardless of terrain and climate.

Even so, scientists have identified similar patterns in birds, who have previously given us great insight into how our language works. City-dwelling birds have actually changed the pitch of their song to compete with the din of cars and people. In a way, they speak a different dialect than their country cousins.

"Say you're a bird in a forest, and some guy's going 'Stree! Stree! Stree!' But because of the environment, what you hear is 'Ree! Ree! Ree!' " linguist Tecumseh Fitch tells Chen. "Well, because you're learning the song, you'll sing 'Ree! Ree! Ree!' "

A similar process could have shaped human languages over time. And perhaps it still does. Though noisy urban dwellings are still relatively new in our past, Maddieson tells Newsweek, "come back in a few more years." Perhaps the speech of city-dwellers will go the way of urban bird song.