Charred remains of ancient seeds from Bihar trace the 3,000-year journey of India’s agriculture

In the eastern Indian state of Bihar, an archaeological excavation at the Uren site has unearthed a massive collection of over 500,000 charred seeds, spanning a 3,000-year period from the Iron Age to the Early Medieval era. Led by researchers from the Birbal Sahni Institute of Palaeosciences and the Archaeological Survey of India, the study provides unprecedented insights into the evolution of agricultural practices in the Ganga Plain region.

The charred remains, preserved through a unique process called carbonisation, allowed scientists to analyze the seeds' shapes, sizes, and origins. By employing flotation techniques to separate the lightweight charred seeds from soil samples, the researchers identified a continuous agricultural history that reveals how early farmers thrived through changing climates and political shifts.

Initially, communities at Uren cultivated a diverse mix of winter crops like barley, wheat, and lentils alongside summer staples such as rice and millets. However, as major Indian empires rose, such as the Mauryas and Guptas, there was a marked transition towards rice as the dominant crop by the Sunga-Kushana period around 200 BCE. This shift indicates a deliberate intensification of farming practices, driven by advancements in irrigation and tools to support burgeoning urban populations.

The study employed sophisticated analytical methods, including morphometrics to differentiate between wild plants and domesticated crops, and radiocarbon dating to precisely date each seed layer. Remarkably, the Uren site offers a unique, uninterrupted sequence of seeds dating back 3,000 years, offering a comprehensive view of how farming techniques evolved in response to environmental changes.

One of the most significant findings is the resilience of ancient farmers during a period of climate deterioration around 1,300 years ago. As monsoon rains weakened, the region experienced drier conditions. In response, the people of Uren adapted by diversifying their cropping systems, incorporating drought-resistant plants, and constructing irrigation infrastructure to sustain their rice crops.

This adaptive strategy demonstrates the ingenuity and resourcefulness of ancient societies in overcoming environmental challenges.

The discovery of exotic plants such as garlic from Central Asia and tamarind from Africa underscores the extensive trade networks that connected ancient Indian villages, highlighting their role as hubs of cultural and agricultural exchange. This research not only illuminates the history of Indian agriculture but also underscores the enduring legacy of ancient farming innovations that continue to influence modern agricultural practices in the region.