New Delhi, May 15: An unusual partnership that mixed elements of archaeology, mathematics and wildlife science has predicted possible locations of undiscovered inscriptions of Asoka, the celebrated 3rd century Mauryan emperor who left behind his proclamations on boulders and pillars.

Researchers at the University of California Los Angeles (UCLA) have generated a list of 121 sites in India represented on maps as 1km by 1km grids where they say there is a high likelihood of finding undiscovered edicts of Asoka.

Archaeologists have over the past century found 31 edicts inscribed on rocks across a vast geographic area of the subcontinent from Kandahar in Afghanistan to Sasaram in Bihar to Jatinga-Rameshwara in Karnataka and seven edicts on pillars concentrated in the eastern Ganges valley along present-day India-Nepal border. The inscriptions, mainly in Brahmi script, are the first decipherable written records from the Indian subcontinent and provide insights into Asoka's activities and thoughts, including his remorse after a great war in Kalinga and his support of Buddhism.

Now, archaeologist Monika Smith and biogeographer Thomas Gillespie and their colleagues at the UCLA have used a mathematical model to predict locations of edicts yet to be discovered.

"The model predicts a high probability of findings edicts in these locations, but this is only a hypothesis," Gillespie told The Telegraph in a telephone interview. The locations are intended to guide archaeologists and other scholars while they select areas to search for more Ashokan edicts, he said.

The researchers borrowed a tool used in wildlife science called the species-distribution model that uses multiple ecology-related parameters such as the type and abundance of vegetation, terrain features, and climate to predict presence and abundance of specific species. They assumed that because the edicts were intended to spread the emperor's messages, those who etched the inscriptions were likely to pick sites that were near well-populated areas with appropriate boulders or rocks available to serve as the geological substrate.

"We first trained and tested the model through the locations of the 31 known edicts," Gillespie said. "It is clear that these known edicts are located in a non-random pattern."

All the edicts documented thus far have been chance finds during exploration or excavations, with the first recognised inscription linked to Asoka documented in 1915. Archaeological papers suggest that new inscriptions have been discovered about once every decade with the last finding from Rampurwa, Bihar, reported in 2009 by University of Lucknow archaeologist K.K. Thapliyal.

The UCLA team used a database of global population density through ancient times, geological features, and climate parameters such as rainfall to generate the list of 121 sites where, the model predicts, the probability of finding undiscovered edicts is 75 per cent or higher. The locations are clustered in pockets of central India and Afghanistan.

Sections of Indian archaeologists say the list of 121 locations may help narrow down areas for future search and excavations, but other scholars of ancient India caution that the usefulness, if any, of the methodology would depend on whether it yields discoveries.

"In archaeology, as in many other disciplines, the proof of the pudding is in the eating," Nayanjot Lahiri, professor of history at India's Ashoka University, and author of the book Ashoka in Ancient India, published last August, said. "The predictive model outlined will carry credibility if discoveries are made there. That is what will make or unmake the model. We should wait for discoveries to be made before pronouncing on the importance of otherwise of this approach. For scholars and enthusiasts of ancient India, the discovery of an Asokan edict is worth much more than a model which predicts such discoveries will take place."

But others believe the modelling efforts could support search strategies.

"This is a very important period of Indian history; even if we were to find just a few more edicts, it would be worth the effort," said Sheila Mishra, an archaeologist at Deccan College, Pune.