Humans couldn't pronounce 'f' and 'v' sounds before farming developed, suggests a new study, which showed that diet-related changes led to new speech sounds that are now found in half the world’s languages. It takes less pressure to chew softer foods, so the jawbone doesn’t grow to be so large.

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Humans couldn't pronounce 'f' and 'v' sounds before farming developed, suggests a new study, which showed that diet-related changes led to new speech sounds that are now found in half the world’s languages. It takes less pressure to chew softer foods, so the jawbone doesn’t grow to be so large.