אישי

Prof. Stephen Weiner (sitting, second from left) and Dr. Elisabetta Boaretto (standing, fourth from left) with the international team of researchers

China gave the world porcelain: The name of the country is synonymous with elegant ceramic dinnerware. But did China also give the world its first clay pottery? Until now, there have been several contenders for that title, most notably Japan and eastern Russia. Now, Dr. Elisabetta Boaretto of the Helen and Martin Kimmel Center for Archaeological Science and Bar-Ilan University, and Prof. Stephen Weiner, Head of the Kimmel Center in the Weizmann Institute’s Faculty of Chemistry, along with an international team of researchers, have conclusively dated the most ancient pottery yet discovered to more than 18,000 years ago. This gives the award for the earliest known use of ceramic technology to the prehistoric residents of the Hunan region in southern China. The findings, which were recently published in the Proceedings of the National Academy of Sciences (PNAS), USA, show that clay pottery was being produced at least 1,000 years earlier than previously thought.
 

“Humans have used fire for around a million years, but it was just a ‘short while ago’ – less than 20,000 years – that they discovered how to bake clay-rich soil into vessels,” says Weiner. It was a technological feat that took place even before the era of great social and economic change accompanying the transition to permanent agricultural settlement known as the Neolithic. Up to now, however, dating either the sediment layers or the pottery and other artifacts found in ancient caves has been next to impossible. Standard dating techniques based on radioactive carbon have not produced reliable results, mainly due to the difficulty of finding well-preserved datable material.
 

Boaretto, Weiner and their colleagues tailored a new, multi-pronged approach to overcome these difficulties. First, they learned the layout of the Yuchanyan Cave in Hunan Province in detail, including each of its archaeological strata, before assembling a large collection of charcoal fragments and bones – about 150 altogether – for testing. Because the pottery can’t be directly dated, they paid special attention to samples from layers in which clay shards were also found. “The accepted method is to take as many datable samples as possible; but we chose a different approach,” explains Boaretto. She developed a strict system of “quality control” to sort the samples. Using an infrared spectrometer, the team identified the ones most likely to yield reliable data. Only samples that contained original carbon and hadn’t been contaminated with foreign carbon were used to date the various strata.
 

About 40 of the samples proved to be clean and well preserved, and these were subjected to radiocarbon dating. To confirm their analysis and check the fit between the radiocarbon dating of bone and charcoal and the age of the pottery vessels buried in the cave, the research team carried out extensive mapping of the cave’s strata and a micro-morphological analysis of its sediments. By the time they were done, they had produced a consistent sequence of dates for human presence in the cave, including ages for the pottery found there. The most ancient clay vessels were found to be around 18,300 years old – the oldest ever discovered.
 

Since the layers were mostly laid down by human activities – ash from fires, clay used to prepare fireplaces, remains of meals, etc. – the analysis of the cave sediments revealed a bit about the people who lived there. It seems the cave’s inhabitants dined on wild boar, turtles, fish, small mammals, and also wild rice. The Yangtze River basin in southern China was a center of settlement in the Late Paleolithic, and it’s likely that many of the caves in the region were similarly inhabited by such groups in the very early stages of transition from nomadic hunting to agricultural settlement, when they were just beginning to use clay vessels.
 

Although these findings have conclusively dated the earliest known pottery and shed light on the beginnings of human settlement in southern China nearly 20,000 years ago, a number of mysteries remain. For instance, why is there such a large gap between the use of pottery in eastern Asia and its adoption in the West? People in the Levant began producing clay vessels only some 10,000 years later than residents of southern China. Other technologies, in contrast – including the use of bronze and domestication of plants – arose earlier in western Asia. Could this technology have arisen independently in a number of places, or did it begin in China and then gradually spread throughout eastern Asia?

Prof. Stephen Weiner’s research is supported by the Ilse Katz Institute for Material Sciences and Magnetic Resonance Research; the Helen and Martin Kimmel Center for Archaeological Science; the Maurice and Vivienne Wohl Charitable Foundation; and the estate of George Schwartzman. Prof. Weiner is the incumbent of the Dr. Walter and Dr. Trude Borchardt Professorial Chair in Structural Biology.

Hunan, in southern China, site of Yuchanyan Cave