Large-Scale Storage of Grain Surplus in the Sixth Millennium BC: The Silos of Tel Tsaf
Garfinkel, Yosef, Ben-Shlomo, David, Kuperman, Tali, Antiquity
Silos for the storage of grain have been an essential aspect of all agricultural communities throughout the ages. Harvested crops need to be kept for at least a year until the next harvest. When the amount of stored grain is larger than that necessary for the consumption of the people harvesting it, a surplus is created. This surplus can become a commodity, which can be exchanged for other products. In human history, the first stage in the accumulation of wealth was the production of agricultural surpluses, in the form of grain and livestock. Surplus accumulation facilitated the development of full-time craft specialisation and socioeconomic distinctions, the rise of urbanism and state formation. These aspects were already discussed by Gordon Childe in his groundbreaking essay The Urban Revolution (1950). The importance of silos has been noted in various case studies, usually associated with urban and state-level societies (Currid 1985: 98-100; Mazar 2001; Pfalzner 2002).
In the past, as wdl as today, several universal principles have guided the construction of silos worldwide (Currid 1985: 104-9; Beedle 2001). These principles can be seen on different scales, from the individual far to that stores a few tons of grain to large harbour installations that handle millions of tons each year:
1. A cylindrical shape, which better withstands the pressure of the grain, distributed evenly onto the sides of the silo and does not create stress on the base or corners of a rectilinear shape. A rounded wall requires less building material than rectilinear walls confining an equal space.
2. A number of silos are built in close proximity. It is easier to handle storage in a number of smaller silos than in one large installation, making it possible to store grain of different years, or different crops, separately. In the case of spoilage by fire, humidity, rodents or insects, not all the stored material will be affected.
3. Organisation in rows, adjacent to each other, optimising their arrangement within a confined space.
Tel Tsaf indicates that such silos were built in the ancient Near East as early as the late sixth millennium BC. In addition to their importance in the history of storage, they shed light on surplus accumulation and concentration of wealth on a scale never before reported from the Proto-historic Near East. Their location not in Greater Mesopotamia but in the southern Levant is surprising, as this area has not previously revealed evidence of economic and social complexity at such an early date.
Tel Tsaf is located in the central Jordan Valley near Beth Shean (Israel new grid map reference 2015.2024; Figure 1). In 2004-2007 four excavation seasons were conducted by Y. Garfinkel on behalf of the Institute of Archaeology of the Hebrew University of Jerusalem. Nearly 800[m.sup.2] were opened and a densely built-up settlement has been unearthed (Garfinkel et al. 2007a & b). The site was occupied only during the Middle Chalcolithic period and a date of 5200-4600 cal BC has been established on the basis of eight recently obtained radiometric dates (Figure 2).
[FIGURE 1 OMITTED]
Large-scale excavations exposed a composite array of courtyard buildings combining rectilinear rooms, rounded rooms and 19 rounded silos (Figures 35). The silos, which vary in number and size, are located within large open courtyards. They are well-built mud-brick installations, 1-4m in diameter, with thick paved floors and rounded plastered walls (Figures 6-8). These silos conform with the three principles mentioned above: they are rounded, built in groups and arranged in straight lines.
Several aspects of the material culture of Tel Tsaf indicate the importance of this site. The basic dwelling unit was a large (over 250[m.sup.2]) courtyard structure. The site has an important assemblage, including an elaborate type of pottery, not found in any other site in Israel (Garfinkel 1999:186-8), four sherds of Ubaid pottery (Garfinkel et al. …