A pair of gilded silver dragons found in a 2,000-year-old Xiongnu graveyard in Mongolia. [Photo provided to China Daily]

Test of hypothesis

A 6-hectare heritage site in Dobrovat, dating back to around 4300 BC in the early stages of Cucuteni culture, was the focus of their research. The remains of nine houses had been discovered and the earth, which was used to construct them, was found to be scorched.

Charred earth was also found at sites dating back to the Yangshao period in China, and were widely assumed to be a type of consolidated building material.

According to Wen, however, in Dobrovat, the condition of the 20-centimeter-thick blocks of earth－some of them vitrified at a temperature of over 1,000 C－instead suggested that these dwellings had been deliberately burned to the ground.

"It's likely that these intense fires were not accidentally caused by war or looting," he says. "This may reveal that certain religious rituals took place when people abandoned their homes. This inspired our future studies into similar phenomenon in China."

Since no Cucuteni culture graveyards have yet been discovered, Wen further speculated that Cucuteni burial customs may have dictated that people were burned together with their houses after they had died.

"After being inhabited for years, the houses were no longer treated as wood and earth," Wen says. "Instead, they were thought to be 'alive'－and something spiritual."

He says he has learned a lot from his Romanian colleagues.

"When we conducted careful and detailed analysis of these earth structures, just like examining and rebuilding the broken pottery discovered there, they helped us reconstruct the original appearance of these dwellings and reveal an abundance of easily overlooked historical information."

Chinese archaeologists will also help to solve problems at the site.

Since two-thirds of the Dobrovat site is covered by thick forest, most electronic detectors don't work there. Wen says they will take a "Luoyang spade"－a traditional tube-shaped testing tool widely used by Chinese archaeologists to examine the layers of soil to locate possible underground relics－to Dobrovat for the second phase of excavations later this year.

Although two months seemed too short a time to completely answer the questions raised by Andersson a century ago, Wen says the hypothesis of communication between the Cucuteni and Yangshao cultures, separated by 7,000 kilometers, seems improbable.

"It was our romantic imagination before we did field research in Dobrovat," he says. "However, despite the similar patterns on the colorful pottery, other unearthed objects from the two cultures appear markedly different.

"Nevertheless, their apparent 'similarities'－even the patterns of colorful potteries－seem to reflect that people in different regions shared paths in social development carried over from Neolithic times to the Bronze Age. Comparative cross-cultural studies require an insight into historical precedents rather than by simply examining scattered signals."