Indo-European languages are spoken by nearly half of the world’s population, and it is widely believed that they all share a common ancestor. For centuries, linguists have argued about the origins of this group of native languages, and now researchers have traced the roots of all Indo-European languages back to more than 8,000 years ago.
The new study, published in the journal Science, created a dataset of 170 core words from 161 Indo-European languages, including 52 historical languages such as Ancient Greek, Classical Latin and Old English. By analyzing patterns and similarities between different languages, the researchers were able to create a “language tree” showing how new dialects emerged as older languages disintegrated.
So far, two main theories have dominated the debate. The first is known as the steppe hypothesis, according to which an ancestral language appeared in the Pontic-Caspian steppe no earlier than 6,500 years ago and then spread throughout Eurasia along with horse herding. The second theory, known as the farming hypothesis, suggests an earlier origin, about 9,500 years ago in the part of the Fertile Crescent that today includes Turkey and Iran. According to this hypothesis, the emergence of Indo-European languages in this region was facilitated by the spread of agriculture across Eurasia.
Moving in the opposite direction, the authors of the study traced the origin of Indo-European languages back to 8,120 years ago and suggested that the primordial languages did indeed originate in the Fertile Crescent region. However, according to the model developed by the researchers, the language did not spread across Europe and Asia in a single wave, as it was assumed within the framework of the farming hypothesis, but split into several branches, some of which are much older than others.
For example, the Albanian, Greek, Armenian and Anatolian branches of the tree separated from the ancestor language about 7 thousand years ago. However, it was not until about 2,000 years later that a second wave of expansion occurred, when Indo-European languages spread across the steppe with cultures such as pit and cord cultures.
This is supported by genetic studies, which have shown that a major migration across the steppe into Europe occurred about 5,000 years ago.
“It is estimated that Germanic and Celtic languages diverged from each other [around 4,890 BCE], and Italic languages slightly earlier [around 5,560 BCE],” the study authors write. “The Balto-Slavic language is less closely related to these three languages and separated from them earlier [about 6460 years before present].”
Thus, overall, the language tree does not support either the steppe or land-grass hypotheses, but offers an alternative “hybrid” model, according to which Indo-European languages originated in Anatolia and then spread in several directions. One of these branches emerged from the Pontic-Caspian steppe, giving rise to many of the languages that have dominated Western Europe for the past five millennia.
“Thus, ancient DNA and linguistic phylogenetics suggest that the solution to the 200-year-old Indo-European enigma lies in a hybrid of the farming and steppe hypotheses,” the researchers conclude.
