From CK Nayak
NEW DELHI, Sep 18: Days after UNESCO included Krem Mawmluh in Meghalaya in its tentative list of World Heritage Sites, a renowned American paleoclimatologist said the cave’s current geological age is not backed by enough scientific proof.
In a new study published in the Journal of Geography, Raymond S. Bradley argued that the evidence used to define the Meghalayan Age is too weak to justify its global status. He called for this age, a subdivision of Earth’s recent history formally named after Meghalaya, to be scrapped from the official geological time scale.
“The evidence (for Meghalayan Age) is not strong enough,” said the scientist who studies ancient climates. “For a new stage boundary to be valid, the change must be clear and widespread, and that is simply not the case for 4,200 years, which defines the beginning of the current Meghalayan age in the Holocene Epoch,” Prof Bradley of the University of Massachusetts said. The Meghalayan Age cave in Sohra, rich in speleological features and home to living ecosystems, is among seven new natural properties from India in the tentative list of UNESCO’s World Heritage Sites. The only other site in the list from the Northeast is the Naga Hill Ophiolite in Kiphire, a rare, exposed section of ancient oceanic lithosphere that was emplaced onto continental crust during the India-Myanmar collision.
The Meghalayan Age was ratified in 2018 by the International Commission on Stratigraphy, a body of the International Union of Geological Sciences. It marked the most recent stage of the Holocene Epoch, beginning around 4,200 years ago, and was based on stalagmite records from the Mawmluh Cave.
The decision drew wide attention in India, with Meghalaya celebrated as the “birthplace” of a new slice of Earth’s timeline. The state government and scientists at the time hailed it as a matter of pride, projecting Meghalaya’s caves onto the global scientific stage.
The Meghalayan Age was linked to a supposed global drought that disrupted civilisations across West Asia and beyond. However, according to Prof Bradley, the data only shows regional climate anomalies, not a globally coherent shift.
“There would not be any stage boundary, because there was nothing that could be defined with global significance,” he explained. The scientist also stressed that while the location in Meghalaya gave the naming symbolic importance, the real issue is scientific.
“I did not see any cultural significance, though of course that may be so in Meghalaya,” Prof Bradley noted. He said his motivation was simple: to revisit what he sees as an unsupported decision.
“I found the argument was unreasonable and not supported by the facts. I had no role in the original decision,” he said, adding that his paper will encourage wider debate among geoscientists.
The call to scrap the Meghalayan Age comes at a time when the scientific community remains divided over another contentious issue: the proposed Anthropocene Epoch, defined by humanity’s impact on Earth. Prof Bradley, however, does not see the two debates as directly connected.
“That’s a different topic and not relevant for the validity of the 4.2 ka stage boundary,” he clarified. For the wider public, the debate may feel distant. “I am not sure if it matters outside the scientific community,” he admitted.
Still, within geology, the implications are significant. Subdivisions of the Holocene form part of the global geological timescale, the reference framework used by scientists and educators worldwide. If Prof Bradley’s call gains traction, Meghalaya’s unique place in that timeline may be reconsidered — and possibly erased.
