"I am tempted to believe that the pits were formed as a direct result of the demolition of Sanxingdui's temple of worship and everything inside, a seemingly crazy act propelled by the abandonment of the original belief to which the temple had been dedicated."

In searching for clues for this religious and cultural turnaround, Hu looked at the 4th-century book The Chronicles of Huayang, which gave a fleeting mention of a certain ruler of the ancient kingdom of Shu "starting to build ancestral halls". (Huayang was an ancient name for the land of Shu.)

"Judging by all evidence, including the many bronze altars unearthed from the Sanxingdui site, the ancient kingdom, located within the upper reaches of the Yangtze River, was a theocracy with a belief system closely linked to the ones adopted by prehistoric cultures along the middle and lower reaches of the river," Hu says.

"What they had in common was the embrace of shamanism, in which shaman (wu in Chinese), believed to have the ability to communicate with spirits, played significant roles in society as intermediaries between the human world and spiritual realm."