• A groundbreaking discovery in Assam’s Makum Coalfield has revealed 24-million-year-old fossilized leaves, offering a rare glimpse into South Asia’s prehistoric climate and biodiversity. 

• Researchers from the Birbal Sahni Institute of Palaeosciences (BSIP), an autonomous institute of Department of Science and Technology (DST), identified the fossils as belonging to the Nothopegia genus — marking the oldest known record of this plant in the world.

• The findings, published in Review of Palaeobotany and Palynology, highlight a dramatic ecological shift that reshaped India’s flora over millions of years.

• The fossil leaves, dating back to the late Oligocene epoch (24–23 million years ago), closely resemble modern Nothopegia species found today in the Western Ghats, a biodiversity hotspot thousands of kilometers away.

• This discovery suggests that Northeast India once hosted a warm, humid climate similar to the Western Ghats, allowing tropical plants like Nothopegia to thrive. 

• However, tectonic upheavals — particularly the rise of the Himalayas — transformed the region’s climate, making it unsuitable for such species. 

• As temperatures and rainfall patterns shifted, Nothopegia vanished from Assam but survived in the stable Western Ghats, where it persists as a living relic of an ancient ecosystem.

• To decode Assam’s pre-historic environment, scientists used herbarium comparisons, cluster analysis, and climate modelling (CLAMP). Their findings confirm that the region was once far warmer and wetter, supporting lush tropical vegetation. 

• The study also illustrates how geological forces and climate change drove species migration, with some plants finding refuge in more stable regions like the Western Ghats.

• The research carries urgent implications for today’s climate crisis. Unlike gradual ancient shifts, current environmental changes are occurring at an unprecedented pace, threatening biodiversity. 

• Understanding how Nothopegia once migrated and found refuge helps scientists predict how modern plants might respond to global warming. 

• It also highlights the importance of protecting biodiversity refuges like the Western Ghats, where ancient lineages continue to persist against the odds.

(The author is a trainer for Civil Services aspirants.)