Middens are prehistoric rubbish or garbage heaps. The word midden in archaeology is a term that is truly a product of this discipline and is now part of its everyday vernacular. Middens are one of the most useful deposits for archaeologists because nearly everything a group of people use in their daily lives eventually will be lost or discarded, and most of what is thrown away ends up in a midden. These archaeological deposits can contain everything from broken tools to used-up artifacts, shells, plant materials, bones, charcoal and ash from fires, and even human remains. Midden contents indicate where people went to obtain their food, what proportions of different foods comprised their diets, and how the types of food and other items may have changed over different seasons or over long periods of time. The deposition of grease and other decomposing organic materials from human habitation means that midden soils typically are darker in color and contain more nitrogen than the natural surrounding soils. Because they are most commonly associated with the accumulation of mollusk shells from food consumption, middens often are referred to as shell middens, shell heaps, or shell piles.
The word midden is derived from a Scandinavian word that means kitchen leavings and was traditionally called “kitchen midden,” which is a literal translation of the Danish word kokkenmoddinger. Japetus Steen-strup, a Danish zoologist, first noted that these deposits were not natural but in fact were the result of human waste accumulation and thus would be of archaeological interest. In 1848, the Royal Academy of Copenhagen established a committee to study these kitchen midden sites, and the committee members were the archaeologist Jens Jacob Asmussen Worsaae, the geologist Johan Georg Forchhammer, and Steenstrup. Their findings demonstrated that these midden deposits could assist not only in the interpretation of past environmental conditions but also in the understanding of prehistoric artifacts. They also helped to prove the viability of the “three-age system,” that is, the development over time of stone tools to bronze tools and then to iron tools. Investigations of mollusk shell piles associated with Danish Mesolithic sites, and the heated debate surrounding the origin of these deposits, led Steenstrup to seek similar materials from kitchen midden sites in Greenland during the 1870s. Unlike the Danish sites, these refuse piles were composed primarily of seal and caribou bones. However, the artifacts associated with these tossed food remains documented several cultural layers of deposition and the presence of an early Arctic culture, which made tiny stone tools, that was distinctly different from more recent Inuit deposits.
Coincident with Steenstrup’s Greenlandic research, the American geologist William Healey Dall began systematic excavation of stratified “shell heaps” on the Aleutian Islands and interpreted these as three distinct evolutionary stages of subsistence based on their faunal composition and recovered artifacts. Across the Pacific, excavations were under way on the Omori shell midden near Tokyo Bay, where the American archaeologist Edward Morse identified distinct cord-marked pottery that is now recognized to be some of the oldest pottery in the world and attributed to the Jomon culture. In 1902, the German archaeologist Max Uhle excavated a large shell midden at Emeryville on the east shore of San Francisco Bay. Uhle was able to determine two major components characterized in part by the dramatic shift from oysters to clams. Since that time, shell middens have been investigated on nearly every coast from the Shetland Islands to South Africa and from New Zealand to Florida.
- Dall, W. H. (1877). On succession in the shell-heaps of the Aleutian Islands. Contributions to North American Ethnology, 1, 41-91.
- Daniel, G. (1976). 150 years of archaeology. Cambridge, MA: Harvard University Press.
- Fagan, B. M. (2005). A brief history of archaeology: Classical times to the twenty-first century. Upper Saddle River, NJ: Pearson Prentice Hall.
- Uhle, M. (1907). The Emeryville Shellmound. University of California Publications in American Archaeology and Ethnology, 7, 1-107.