Using a computer simulation, a British researcher says he's examined the rate of change of words in languages to reveal the oldest English-sounding words, which would have been used by Stone Age humans 20,000 years ago.

Among the Stone Age words that presumably would've sounded then much like they do now in the English language: I, we, two and three.

The study concludes that the frequency with which a word is used relates to how slowly it changes through time, so that the most common words tend to be the oldest ones. While it cannot necessary predict exactly what words were used 20,000 years ago — there's little to go on, since writing was invented only about 5,000 years ago — it makes some interesting guesses.

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