There are more than 7,000 languages used across the globe today, but this is just a fraction of what once existed. In a new study, researchers homed in on what they call the “golden age” of language, when linguistic diversity reached its peak. They suggest that this was somewhere between 1,000 to 3,000 years ago and that people may have used up to 10 times as many languages as we do today.

Producer Kathleen Davis chats with language researcher Damián Blasi about why there were so many more languages—and what happened to them.

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