Language Log

No longer lost for words: How researchers rediscovered the mother of all mother tongues

Researchers have developed a method that uses sound waves to rediscover the long-lost Proto-Indo-European language, from which most modern languages evolved.

No matter whether you speak English or Urdu, Waloon or Waziri, Portuguese or Persian, the roots of your language are the same. Proto-Indo-European is the mother tongue – shared by several hundred contemporary languages, as well as many now extinct, and spoken by people who lived from about 6,000 to 3,500 BC on the steppes to the north of the Caspian Sea.

They left no written texts and although historical linguists have, since the 19th century, painstakingly reconstructed the language from daughter languages, the question of how it actually sounded was assumed to be permanently out of reach.

Now, researchers at the Universities of Cambridge and Oxford have developed a sound-based method to move back through the family tree of languages that stem from Proto-Indo-European. They can simulate how certain words would have sounded when they were spoken 8,000 years ago.

The shape of sounds

Remarkably, at the heart of the technology is the statistics of shape.

“Sounds have shape,” explained Professor John Aston, from Cambridge’s Statistical Laboratory. “As a word is uttered it vibrates air, and the shape of this soundwave can be measured and turned into a series of numbers. Once we have these stats, and the stats of another spoken word, we can start asking how similar they are and what it would take to shift from one to another.”

A word said in a certain language will have a different shape to the same word in another language, or an earlier language. The researchers can shift from one shape to another through a series of small changes in the statistics. “It’s more than an averaging process, it’s a continuum from one sound to the other,” added Aston, who is funded by the Engineering and Physical Sciences Research Council. “At each stage, we can turn the shape back into sound to hear how the word has changed.”

Rather than reconstructing written forms of ancient words, the researchers triangulate backwards from contemporary and archival audio recordings to regenerate audible spoken forms from earlier points in the evolutionary tree. Using a relatively new field of shape-based mathematics, the researchers take the soundwave and visualise it as a spectrogram – basically an undulating three-dimensional surface that represents the shape of that sound – and then reshape the spectrogram along a trajectory signposted by known sounds.

While Aston leads the team of statistician shape-shifters in Cambridge, the acoustic-phonetic and linguistic expertise is provided by Professor John Coleman’s group in Oxford.

Number game

The researchers are working on the words for numbers as these have the same meaning in any language. The longest path of development simulated so far goes backwards 8,000 years from English one to its Proto-Indo-European ancestor oinos, and likewise for other numerals. They have also gone forwards from the Proto-Indo-European penkwe to the modern Greek pente, modern Welsh pimp and modern English 
five, as well as simulating change from Modern English to Anglo-Saxon (or vice versa), and from Modern Romance languages back to Latin.

Other audio demonstrations are available here.

“We’ve explicitly focused on reproducing sound changes and etymologies that the established analyses already suggest, rather than seeking to overturn them,” said Coleman, whose research was funded by the Arts and Humanities Research Council.

They have discovered words that appear to correctly fall out of the continuum. “It’s pleasing, not because it overturns the received wisdom, but because it encourages us that we are getting something right, some of the time at least. And along the way, there have also been a few surprises!” The method sometimes follows paths that do not seem to be etymologically correct, demonstrating that the method is scientifically testable and pointing to areas in which refinements are needed.

Remarkably, because the statistics describe the sound of an individual saying the word, the researchers are able to keep the characteristics of pitch and delivery the same. They can effectively turn the word spoken by someone in one language into what it would sound like if they were speaking fluently in another.

Spectrograms showing how the shape of the sound of a word in one language can be morphed into the sound of the same word in another language. Credit: John Aston.
Spectrograms showing how the shape of the sound of a word in one language can be morphed into the sound of the same word in another language. Credit: John Aston.

Evolution of language

They can also extrapolate into the future, although with caveats, as Coleman described. “If you just extrapolate linearly, you’ll reach a point at which the sound change hits the limit of what is a humanly reasonable sound," he said. "This has happened in some languages in the past with certain vowel sounds. But if you asked me what English will sound like in 300 years, my educated guess is that it will be hardly any different from today!”

For the team, the excitement of the research includes unearthing some gems of archival recordings of various languages that had been given up for dead, including an Old Prussian word last spoken by people in the early 1700s but borrowed into Low Prussian and discovered in a German audio archive.

Their work has applications in automatic translation and film dubbing, as well as medical imaging (see panel), but the principal aim is for the technology to be used alongside traditional methods used by historical linguists to understand the process of language change over thousands of years.

“From my point of view, it’s amazing that we can turn exciting yet highly abstract statistical theory into something that really helps explain the roots of modern language,” said Aston.

“Now that we’ve developed many of the necessary technical methods for realising the extraordinary ambition of hearing ancient sounds once more,” added Coleman, “these early successes are opening up a wide range of new questions, one of the central being how far back in time can we really go?”

Audio demonstrations are available here: www.phon.ox.ac.uk/jcoleman/ancient-sounds-audio.html

This article first appeared on the University of Cambridge website.

Support our journalism by subscribing to Scroll+ here. We welcome your comments at letters@scroll.in.
Sponsored Content BY 

Get ready for an 80-hour shopping marathon

Here are some tips that’ll help you take the lead.

Starting 16th July at 4:00pm, Flipkart will be hosting its Big Shopping Days sale over 3 days (till 19th July). This mega online shopping event is just what a sale should be, promising not just the best discounts but also buying options such as no cost EMIs, buyback guarantee and product exchanges. A shopping festival this big, packed with deals that you can’t get yourself to refuse, can get overwhelming. So don’t worry, we’re here to tell you why Big Shopping Days is the only sale you need, with these helpful hints and highlights.

Samsung Galaxy On Nxt (64 GB)

A host of entertainment options, latest security features and a 13 MP rear camera that has mastered light come packed in sleek metal unibody. The sale offers an almost 40% discount on the price. Moreover, there is a buyback guarantee which is part of the deal.

Original price: Rs. 17,900

Big Shopping Days price: Rs. 10,900

Samsung 32 inches HD Ready LED TV

Another blockbuster deal in the sale catalogue is this audio and visual delight. Apart from a discount of 41%, the deal promises no-cost EMIs up to 12 months.

Original price: Rs. 28,890

Big Shopping Days price: Rs. 10,900

Intel Core I3 equipped laptops

These laptops will make a thoughtful college send-off gift or any gift for that matter. Since the festive season is around the corner, you might want to make use of this sale to bring your A-game to family festivities.

Original price: Rs. 25,590

Big Shopping Days price: Rs. 21,900

Fashion

If you’ve been planning a mid-year wardrobe refresh, Flipkart’s got you covered. The Big Shopping Days offer 50% to 80% discount on men’s clothing. You can pick from a host of top brands including Adidas and Wrangler.

With more sale hours, Flipkart’s Big Shopping Days sale ensures we can spend more time perusing and purchasing these deals. Apart from the above-mentioned products, you can expect up to 80% discount across categories including mobiles, appliances, electronics, fashion, beauty, home and furniture.

Features like blockbuster deals that are refreshed every 8 hours along with a price crash, rush hour deals from 4-6 PM on the starting day and first-time product discounts makes this a shopping experience that will have you exclaiming “Sale ho to aisi! (warna na ho)”

Set your reminders and mark your calendar, Flipkart’s Big Shopping Days starts 16th July, 4 PM and end on 19th July. To participate in 80 hours of shopping madness, click here.

Play

This article was produced by the Scroll marketing team on behalf of Flipkart and not by the Scroll editorial team.