HLF 2026 Opening Session Explores the Complex Interplay of Linguistic and Genetic Heritage, Naresh Nunna of Neo Science Hub reports.
The Hyderabad Literature Festival’s Science and the City stream opened Saturday morning with a session that exemplified the kind of intellectual cross-pollination that makes interdisciplinary research both challenging and revelatory. “Tongues and Genes: A Cross-hatch of History” brought together Laura Spinney, acclaimed science journalist and author, and Dr. K. Thangaraj, renowned geneticist, in a wide-ranging conversation moderated by Sahana Ghosh that explored how linguistics, archaeology, and genetics are collaboratively—if sometimes contentiously—rewriting the story of human migration and cultural evolution.
Fluidity of Language & Culture
The session’s central insight emerged early: both language and genetics are far more fluid than our categorical thinking allows. “When we put a label on something, like English or Sanskrit, we’re always talking about a thing that is not one thing,” Spinney explained, challenging the audience to reconsider how we conceptualize linguistic identity. Languages evolve not just through inheritance but horizontally—through borrowing, loaning, and constant adaptation. The same holds true for culture and genetics, though crucially, they don’t always map onto each other in straightforward ways.
Dr. Thangaraj illuminated this complexity through the lens of genetics, noting that in India, where marriage within social groups has been practiced for generations, each community has acquired unique sets of mutations. “Every social group in broad sense has a unique set of mutations. Sometimes they cause diseases,” he explained. “So that means some mutations are specific to one particular group. Therefore, they may be susceptible for a particular disease, not the others.”
This observation reframes diversity not as cultural or linguistic superiority but as biological reality shaped by social practice. “People who relate the language even with God, sometimes they don’t look at God so great, but they look at language much more,” Dr. Thangaraj noted, highlighting the deep emotional attachment communities feel toward their languages—an attachment that genetics reveals is rooted in generations of endogamy and shared mutation patterns.
Migration Puzzle
A significant portion of the discussion centered on one of the most controversial questions in South Asian studies: the nature and impact of ancient migrations, particularly the spread of Indo-European languages. Why, the moderator asked, do we need archaeology and genetics when the question is fundamentally linguistic?
Spinney’s answer was direct: “We’re talking about languages that were prehistoric. That is, before history, that is before writing. They were never written down. So we don’t have any historical text to consult.” Without written records from 5,000 years ago, researchers must turn to the next best sources—archaeological evidence of human movement and settlement, and genetic traces of those migrations in living populations.
Ancient DNA studies have revealed evidence of migrations from the Yamna culture of the steppes toward both Europe and India around 2000 BCE, potentially carrying Indo-European languages. Yet as both speakers emphasized repeatedly, migration doesn’t automatically mean language imposition. “The Scythians came. The Mughals came, and the Greeks came, and none of them left their languages here,” Spinney pointed out. “So it’s not a given that people, when they move, will impose their language by any means.”
Dr. Thangaraj offered contemporary examples: the Siddi communities, Bantu-speaking Africans who settled in India, now speak the local languages of the three different states where they reside. “They have adapted to that language and they have also genetically adapted,” he noted, demonstrating how cultural and genetic adaptation can diverge.
Harappan Question
The elephant in the room—or perhaps more accurately, the elephant that three blind researchers are touching from different sides—is the question of what language the Harappan (Indus Valley) civilization spoke. This remains one of the most contentious debates in South Asian studies.
Spinney acknowledged the uncertainty candidly: “We haven’t deciphered the script of the Indus civilization. Until somebody does that, and it may never happen, or it may do, we will not know.” The Rakhigarhi skeleton, she explained, predates the known migration that could have brought Indo-European languages, yet shows a genetic mix of ancestral South Indian populations and Iranian hunter-gatherers from more than 10,000 years ago. “But it’s already a mix of people from Iran who may or may not have brought some farming knowledge as well,” she said.
The scarcity of ancient DNA from South Asia compounds the challenge. Dr. Thangaraj explained that climatic conditions in the region don’t preserve DNA well, unlike in Europe or Africa. Moreover, thousands of skeletal samples collected during British colonial rule remain in museums abroad, raising questions of repatriation and access.
Despite these limitations, Spinney suggested that hope for resolving the Harappan language question lies not in DNA but in archaeology of texts. “Only a small fraction of the Harappan sites have been excavated. And we know that they had trade links with, for example, Mesopotamia,” she noted. The discovery of a bilingual text—a Rosetta Stone equivalent—could finally unlock the mystery, if such a document exists and can be found.
Challenge of Interdisciplinary Research
Perhaps the session’s most revealing moments came when discussing the difficulties of interdisciplinary collaboration. “People who work on this question themselves from the different communities would say to me, we don’t speak the same languages as each other,” Spinney admitted. She invoked the word “barbarian,” which originally meant in Sanskrit someone who speaks a foreign tongue: “They are barbarians to each other, the linguists, the archaeologists, and the geneticists.”
Dr. Thangaraj noted that geneticists must be careful about which findings they highlight, “particularly if it is more sensitive to the people.” The research touches on questions of identity, migration, and ancestry that carry contemporary political weight—requiring scientists to balance transparency with awareness of how their findings might be misused.
Spinney described her book-writing process as “the most difficult thing I’ve ever done in my life. I thought I was going to go mad at certain points.” The challenge wasn’t just synthesizing three complex fields but navigating their internal disagreements while avoiding cherry-picking data to support any particular narrative. “There are no right answers. There is simply layers, evidence building towards one theory or another,” she explained.
Climate Change
Looking forward, both speakers flagged climate change as a force that will reshape linguistic maps just as it has in the past. A major climate episode around 2200 BCE triggered migrations with lasting linguistic consequences. “If you think of the migration that’s going to be set in train by the climate crisis, that will have linguistic consequences,” Spinney warned.
Most linguists, she noted, consider migration a major driver of language change. In an era of climate-induced displacement, we may witness language evolution in real time—though in a vastly different environment than prehistory, one shaped by widespread literacy, digital communication, and global interconnection.
Despite the uncertainties and unresolved debates, Dr. Thangaraj ended on a hopeful note. After three decades of studying population genetics, the science has evolved from simply understanding population history to delivering a profound social message: “Genetically we are all connected. So the difference what we see superficially now is all happened in the last few hundred or two thousand years. But if you deeply look at our genetics…”
It was a fitting conclusion to a session that demonstrated how the rigorous pursuit of scientific truth—across multiple disciplines, despite methodological differences, and in the face of genuine uncertainty—can reveal our common humanity while celebrating the diversity that makes us distinct. As languages borrow and blend, as genes mix and mutate, and as cultures evolve and adapt, the story that emerges is one of connection, fluidity, and shared heritage stretching back thousands of years.
The session embodied the very best of what science communication can achieve: not providing easy answers to complex questions, but inviting audiences into the messy, exhilarating process of discovery itself.
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