But there is an offshoot: It has the same coiled body, but the snout is further emphasized with wrinkles. The eyes are bigger, rounder, highlighted with circular incised lines. There are also a pair of pricked ears which were to evolve into dragon horns. More adorable than aristocratic, this particular type is aptly dubbed the "pig dragon" and is believed to have a lot to do with pigs being not only an important farm animal, but also associated with the rituals and belief system of Hongshan.

The same circular eyes, long snout and pricked ears would later find their way onto jade dragons or dragon heads from the Lingjiatan and Songze sites — three are on view at the ongoing Shanghai exhibition — and further down the timeline from Liangzhu, where pork had joined fish and rice to form the menu of its ancient people, who built their homes in the watery lowlands.

In the case of the latter, multiple dragon heads also appear on the jade bracelets.

With all that being said, it must be noted that, in reality, this process of transmission was more than complicated, and is anything but linear. To verify all the links along the way — some relatively concrete, others tenuous — researchers, searching for hidden clues, have to be extremely attentive to tiny details, such as the traces left by jadeware craftsmen from different cultures who worked with wood sticks, leather strips and silicon sand, for example.

One inevitable question remains: Had this process somehow come to influence the formation of the ultimate Liangzhu symbol — a manlike figure on top of a mythical beast, carved into a jade cong? The answer, from both Zhou and Fang, is yes.

Both pointed to the jade cong on view at the Shanghai exhibition. A greenish-brownish color, the piece was unearthed 130 km to the northeast of the Liangzhu Ruins, from an archaeological layer of the site believed to have formed during the Liangzhu civilization. (While the Liangzhu civilization covered a large area circling Taihu Lake, the actual Archaeological Ruins of Liangzhu City — the spiritual and political center of this civilization, occupied only a southernmost spot of its territory.)

Two things are noteworthy. First, this particular cong is bracelet shaped, without the edges typical of the Liangzhu-era cong found in a relatively large quantity at the Fanshan Cemetery. Second, being dated to 3300 BC, it is, to this day, the earliest Liangzhu jade artifact that has been found to have borne an image of a beast similar to that of the iconic man-and-beast motif.

"The resemblance is striking: The big eyes are there, so is the wide mouth," says Zhou. "But there are still considerable differences, most notably to the nose, which is only indicated at here, but is articulated in the later versions.

"Many details are missing and the general presentation veers toward the primitive and immature. This is clearly a transitional piece between the definitive Liangzhu beast and some earlier prototype."