A group of researchers from Canada and USA have conducted a wide-ranging survey of the geographical distribution of human genomes and phonemes (speech sounds).
They found that as populations split up and migrate away from one another, genetic diversity within the groups decrease. However, languages show the opposite effect – they become more diverse. This was surprising enough, but the real surprise was that languages did not fit an ‘out of Africa’ pattern.
The researchers wrote: ‘The geographic distribution of phoneme inventory sizes does not follow the predictions of a serial founder effect during human expansion out of Africa.’