For centuries, scholars have attempted to trace the origins of the Indo-European tongues. This group involves more than 400 different tongues, the largest language group on Earth. It includes languages as diverse as Hindi, Russian, Gaelic, Persian, English, Spanish, German, and Greek.
Scholars agree that the languages originated with migration into Europe but are divided on which group of migrants brought the roots of modern language and from where.
The two significant hypothesis are the “Antonlian hypothesis” and the “steppe hypothesis”. The Antolian school holds that following the dawn of agriculture, farmers in search of land moved north from what is now Turkey and brought the language origins with them between 8,000 and 9,500 years ago. The competing steppe hypothesis holds that it was herders from the Eurasian steppe that brought the languages between 5 to 6,000 years ago.
Now, new research using the genomes of 94 ancient Eurasians has provided new clues about who came to Europe when and what they might have brought with them.
One of the arguments of the Antonlian hypothesis has been that the migration from the Steppe wasn’t significant enough to be responsible for language. That is the first point disproved by the new analysis.
“These results challenge the theory that all Indo-European languages in Europe today owe their origin to the arrival of the first farmers from Anatolia more than eight thousand years ago,” said David Reich in a statement.
Reich is a professor of genetics at HMS, associate member of the Broad Institute of Harvard and MIT and senior author of the new study, published online in the March 2 edition of the journal Nature. A previous version of the study appeared in biorxiv.org in February.
“It’s like a detective story. We’re seeing the aftermath of what happened in Europe thousands of years ago. We have clues that these different people were linguistically and genetically related. It’s difficult to figure out how unless we go back to ancient DNA. It’s very contested because there’s no hard evidence. They didn’t write,” said Iosif Lazaridis, a postdoctoral researcher in the Reich lab and co-first author of the paper.
In total, dozens of researchers from around the world contributed to the study by producing genome data from 69 Europeans who lived between 3,000 and 8,000 years ago.
The team targeted and amplified 400,000 potentially relevant variants in the genetics of those 69 subjects and then combined it with 25 previously published human genomes from the same time period.
“We isolated parts of the genome that are most informative about history and sequenced only those. The ability to collect whole-genome data from dozens of individuals at once in this way reflects a sea change in ancient DNA studies,” said Reich.
The first thing they examined was evidence related to the arrival of the first farmers in Spain and Germany.
“The pottery they made looked very different, and some archaeologists have suggested that they were unrelated to each other and came from two separate migration waves. But the genetic data disprove this,” said Reich.
“The first farmers, whether from Hungary, Germany or Spain, are genetically almost identical: They are from the same origin,” said Wolfgang Haak, the paper’s other co-first author.
The researchers also found evidence that early European hunter-gatherers didn’t disappear with the arrival of the farmers. In fact, according to the genetic evidence, the early Europeans saw a resurgence 5,000 to 6,000 years ago.
About 4,500 years ago the team reports another new arrival. A group of ancient humans called the Corded Ware make a genetic appearance in what is now Germany at that time.
These people shared cultural similarities with a group called the Yamnaya, 1,600 miles away in what is now Russia. Until now however there wasn’t genetic evidence of the groups being related. According to the new research, fully three-quarters of the Corded Ware DNA came from the Yamnaya.
“People have either doubted the steppe influenced the Corded Ware population or said perhaps there was limited gene flow, perhaps from a small number of people. Our data show the Corded Ware population actually has most of its ancestry from the steppe,” said Lazaridis.
The researchers believe that the massive migration of these people had a substantial influence on language in Europe.
“it seems likely that the steppe migrants contributed at least some of the Indo-European languages to the area,” said Haak.
The Yamana people also turned out to be the bearers of some long sought after DNA. Modern Europeans are known to be the genetic decedents of ancient hunter-gatherers, immigrant farmers and a previously unknown “Ancient North Eurasian”. That known group has now been identified as the Yamnaya.
“When we first looked at the new data, it was a Eureka moment. Starting around 4,500 years ago, every individual in the Corded Ware and subsequent cultures contained this eastern ancestry, but none had it before that time,” said Lazaridis.
Of course the results cannot conclusively say where Indo-European languages originated. However, by knowing who came from where and when they arrived researchers on all sides of the debate can begin to create better informed hypotheses.
The next step for the team is to examine how ancient immigrants to Europe are related to groups in other parts of the world.
“The priority now is to carry out similar ancient DNA studies to understand how the people of Europe 3,000 to 6,000 years ago were linked with those in Turkey, the Caucasus, Iran and India,” where Indo-European languages are also spoken,” said Reich.