(Transcript from SBS World News Radio)
Australian scientists have slipped another piece into the puzzle about human language development, and it suggests that some three billion of us may have more in common than we think.
Analysis of ancient DNA has shed light on migration patterns, helping researchers trace the origins of some of the most widely spoken languages in the world.
Karen Ashford has the story.
(Click on the audio tab above to hear the full report)
The Indo-European family of languages is complex and extensive.
But precisely how such different sounding languages as English, Spanish and Hindi came to be related has been a point of contention since the 1800s.
Now, Dr Wolfgang Haak from the Australian Centre for Ancient DNA at Adelaide University thinks he and his team may have uncovered a clue - the start of the agricultural era.
"Languages spread easier with a substantial number of people carrying it. Linguists have always argued that the best candidate for the spread of an early Indo-European language must have been based on a substantial population movement. If we look back in the past then there used to be only one predominate candidate that stood out that could not be ignored and that was the expansion of farmers. So people formed the farming language dispersal hypothesis."
Dr Haak specialises in unravelling the oldest secrets of the fundamental human building blocks, DNA, with a particular focus on central Europe.
So, what's a geneticist able to tell us about the origins of how we speak?
After all, language is learned, not genetically imprinted.
Dr Haak thinks by studying genetic sources, he can map population movements and likely language spread.
He's exploring his theory by testing the bones of old farmers, who muscled in on traditional hunter gatherers and had a profound impact on genetic makeup across Europe.
"Expanding farmer communities from the new areas that arrive in Europe around 7,500 years ago and when I say Europe I mean central Europe, where we have a different type of ancestry, a different signal coming in that is unique across all farmers whether we look in Spain or in Germany or Hungary or even in Scandinavia, they all look very similar, which tells us they must have come from a similar geographic origin. If there's a signal strong enough then it is very likely that it must have carried a common language was well."
But he says the big news that's just been published in the prestigious journal Nature is the discovery of a second major movement of people on the verge of the early Bronze Age, about 3,000 years after that first wave.
He thinks this discovery has brought scientists a step closer to pinpointing the very genesis of modern language, and the answer appears to go back to a step of a different kind -- the Russian steppes.
"We see a very strong signal coming from the Eurasian steppes. Genes will always be silent on the type of language that people in the past spoke, but what we see and how we can contribute is that we see particular population turnovers. In our case the second one towards the late Neolithic at the verge of the Bronze Age was unexpectedly big, so we're seeing an influx from the steppe up to three quarters of the ancestry of central Europeans 5,000 years ago comes from the steppe and that is a massive proportion that makes it very likely that it was not only the genes that came from the east, but probably language as well."
Dr Haak says the theory is further supported by common elements in vocabularies, such as similar terms for inventions that were critical to farming like the wheel, the cart, and the domestication of horses.
"It is only plausible to assume that once they share a certain economy, certain markets, social stratification or a social system, then it is only reasonable to assume that it would have had originally the same language before they split up into smaller regions."
It's a theory Dr Haak thinks should give people pause for thought before they criticise on the basis of race or go to war over territory - maybe we're more closely related than we think.
"Why is it relevant? We have three billion speakers in the world speaking one of the 445 languages or dialects that can be summarised under Indo-European. English is one of these, but that also comprises a lot of Hindu Urdu speakers in India, for example. Persian is Indo European, and all the Romance languages - maybe it can all be traced back to a number of mobile steppe cattle herders 5,000 years ago. The nicest feature at the moment, in the current political atmosphere that we see in Europe in particular, is that we are all a nice blend of everything. The genetic makeup was set a long time ago and came from different areas of the world. So, we are all more or less immigrants. And that's for me the most important story - no one can put a claim on any particular country or any particular area - this is all a mixed up mess."