Global linguistic diversity reached its historical peak between 1,000 and 3,000 years ago, when between 20,000 and 75,000 languages may have coexisted around the world. Their number then began to decline, long before the era of European colonialism.
This is the conclusion of an international team of researchers in a study published in the journal Science. The study was co-led by ICREA research professor at Pompeu Fabra University (UPF) Damián Blasi and Claire Bowern of Yale University. Researchers from the universities of Texas and Auckland, the Santa Fe Institute and the Max Planck Institute for Evolutionary Anthropology also contributed to the study.
The research covers a period of around 12,000 years, from the beginning of the Holocene to the present day. Reconstructing the linguistic landscape of the distant past is challenging because writing only emerged around 6,000 years ago. The researchers therefore used ethnographic data and statistical models to estimate the size of prehistoric populations and their ethnolinguistic groups.
At the beginning of the Holocene, the world’s population is estimated to have been around 4–7 million people, while the number of languages may have ranged from 4,500 to 6,200.
Linguistic diversity increased steadily with the development of agriculture. Population growth and the spread of farming communities meant that groups became increasingly separated geographically, creating conditions for linguistic differentiation and the emergence of new languages.
The peak came 1,000–3,000 years ago. After that, however, the number of languages began to decline sharply.
Researchers point to the expansion of large empires, including the Roman Empire, as one of the factors behind this decline. Contacts between previously isolated populations became more frequent, while the languages, cultures and political institutions of imperial centres spread across new territories.
The spread of infectious diseases also played a role. Epidemics caused significant population losses and contributed to the disappearance of some linguistic communities.
The findings therefore challenge the view that the large-scale decline in linguistic diversity began mainly with European colonialism around 500 years ago. According to the researchers, the process had already begun much earlier.
Today, around 7,500 languages are spoken worldwide. Asia accounts for approximately 2,300 and Africa for around 2,000. Europe has considerably less linguistic diversity, with only 200–300 languages spoken across the continent.
“The languages we see today are survivors of a massive and highly selective historical bottleneck,” said Damián Blasi.
The researchers stress that the loss of languages today is not unique in historical terms. In the past, there were periods when linguistic diversity declined even more rapidly.
