Scientists Discover Molecular Evidence of Wildfires in Ancient Gondwana Forests 250 Million Years Ago

In a major breakthrough in palaeoclimate and Earth history research, scientists from the Birbal Sahni Institute of Palaeosciences (BSIP), Lucknow, have uncovered molecular evidence of massive wildfires that swept across the ancient Gondwana forests nearly 250 million years ago during the Permian period. The findings provide fresh insights into how prehistoric wildfires influenced Earth’s climate systems, vegetation patterns, coal formation, and ecosystem evolution long before the emergence of modern human civilisation.

The research, carried out by BSIP scientists under the Department of Science and Technology (DST), Government of India, introduces an advanced multi-proxy scientific approach that significantly improves the understanding of ancient wildfire activity preserved in sedimentary rocks and coal-bearing formations of India’s Gondwana basins.

The study focused on the Godavari Valley Coalfield, one of India’s major Gondwana sedimentary basins known for preserving geological records of ancient forests and climatic conditions. Researchers analysed microscopic organic residues preserved in the sediments to reconstruct wildfire events that occurred during the Permian period, a geological era marked by dramatic climatic shifts and ecological transformations.

For years, scientists investigating palaeofires primarily relied on macrocharcoal evidence and microscopic examination of sedimentary organic matter. Earlier studies in Indian Permian deposits had already provided the first large-scale evidence of ancient wildfire activity through macrocharcoal-based investigations. These studies highlighted the presence of fire-altered plant material within coal-bearing sedimentary sequences.

However, researchers faced a major challenge in accurately distinguishing between different forms of microscopic charcoal particles, especially oxidized opaque phytoclasts (OX-CH) and fire-induced opaque phytoclasts (PAL-CH). Traditional microscopic techniques often created ambiguity regarding the origin, intensity, and nature of the fire events that produced these particles.

Recognising the limitations of conventional approaches, the BSIP research team adopted an innovative combination of palynofacies analysis and advanced molecular spectroscopy techniques to study ancient fire residues with far greater precision.

Palynofacies analysis involves the study of microscopic organic matter, spores, pollen, and plant residues preserved within sedimentary rocks. To strengthen their findings, the researchers integrated this method with Raman spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy — sophisticated molecular tools capable of identifying structural and chemical changes in carbon-rich materials caused by combustion and thermal alteration.

The research team, comprising scientists Neha Aggarwal, Shivalee Srivastava, and Runcie Paul Mathews, successfully bridged the gap between visual identification of palaeofire residues and their molecular-level characterization. Their work enabled the precise differentiation between high-intensity wildfire residues (h-PAL-CH) and low-intensity wildfire residues (l-PAL-CH) based on morphology, optical properties, preservation state, and molecular signatures.

One of the major findings of the study was the identification of clear molecular evidence of combustion preserved in the ancient sediments. Raman spectroscopy revealed well-developed second-order spectral features associated with structural ordering of carbonaceous material and the formation of Poly Aromatic Hydrocarbons (PAHs), which are characteristic indicators of high-temperature burning processes.

Similarly, FTIR spectroscopy detected specific chemical functional groups associated with thermal alteration pathways, confirming the fire-induced origin of the organic matter. Together, these spectroscopic signatures provided compelling evidence of widespread palaeowildfire activity in the ancient Gondwana ecosystem.

The integrated scientific approach has significantly improved the accuracy of identifying ancient fire-derived organic particles and reconstructing prehistoric wildfire regimes. According to researchers, the findings not only help understand Earth’s geological and climatic history but also offer valuable lessons for studying modern climate change and wildfire behaviour.

The Permian period, which occurred around 299 to 252 million years ago, was a critical phase in Earth’s history marked by large-scale environmental changes, fluctuating atmospheric oxygen levels, shifting vegetation patterns, and the eventual Permian mass extinction event — the largest extinction event known in Earth’s history.

Scientists believe that understanding ancient wildfire patterns can provide important clues about how ecosystems respond to extreme climate conditions, changing atmospheric composition, and environmental stress. The new findings suggest that wildfires played a major role in shaping ancient forest ecosystems, influencing carbon cycling, and contributing to coal formation processes in Gondwana landscapes.

Researchers noted that such studies are becoming increasingly relevant in the present era of accelerating climate change, rising global temperatures, and increasing frequency of extreme wildfire events worldwide. Ancient palaeofire records can help scientists improve long-term climate models and better understand how ecosystems may react to future environmental disturbances.

The study also contributes significantly to India’s growing role in advanced Earth science research, palaeobotany, and climate reconstruction studies. The use of cutting-edge molecular techniques in palaeoscience marks an important advancement in interdisciplinary geological research in the country.

The findings have been published in the internationally reputed journal Geological Journal (Wiley), further highlighting the global scientific importance of the work.

Experts believe that integrating palaeontology, geochemistry, spectroscopy, and climate science will open new pathways for understanding Earth’s deep-time environmental history and its implications for future planetary sustainability.