New research by Dr. Melinda Zeder, Curator of Old World Archaeology & Zooarchaeology at the National Museum of Natural History, and Dr. Brian Hesse of the University of Alabama at Birmingham, shows that goats, hunted in the region since the time of Neanderthals, were now being bred and herded instead. Their findings on this historic shift, which forever changed both the societies of human herders and the ecology of regions where goats and other livestock animals lived, were reported in the March 24, 2000 issue of Science.
- (Photo by Carl Hansen, Smithsonian Institution)
Toe bones of a goat (Capra hircus) found at the 10,000 year old settlement of Ganj Derah, Iran give us new insights into the origins of animal domestication in the Near East.
Judging from sizes of the bones of modern wild goats, the larger 10,000 year old toe bone (a first phalanx) on the right was likely a male, while the smaller bone on the left was a female. The unfused base of the male toe bone is a skeletal sign that this individual was killed before it reached maturity. In contrast the fully fused toe bone of the female indicates that this animal was killed at an older age. This pattern of culling young males, and delayed slaughter of female breeding stock is found in domestic herds today.
- Aerial Photo of the site of Ganj Dareh, Kermanshah Valley, Iran under excavation in the 1970s.
- New research confirms that this site contains the earliest directly dated evidence of livestock domestication in the world. (Photo supplied by Brian Hesse, University of Alabama at Birmingham).
Click for larger image.
Archaeologists have long struggled to identify the origins of animal domestication in many cultures worldwide, from the Fertile Crescent region of the Near East to the tip of South America. They long thought that domesticated animals became smaller in body size than their wild ancestors or contemporaries. Zeder and Hesse’s new work challenges the idea that size reduction serves to mark the initial domestication of goats, the earliest domesticated livestock species. Using modern wild and domestic goat skeletons of documented age and sex, Zeder discovered that sex, not domestic status, is the single most important factor affecting body size. This, and the ability to determine age of death from the state of bone fusion of various skeletal elements, made it possible to reconstruct sex-specific slaughter profiles for ancient animals as an alternative, and more powerful, means of marking early animal domestication
How? By knowing that a hunter is more likely to target larger adult individuals (generally males) which return more meat for every kill while the herder, interested in promoting the productivity of the herd, is likely to kill males at young ages — and allow females and a few breeding males to survive much longer. These different slaughter strategies leave behind distinctive signature profiles in the ages and sexes of the animal bones accumulated in the trash dumps of the living sites kept by herders and hunters. The very earliest stages of animal domestication can thus be seen in the archaeological record before the bones of these first domesticates reveal any marked changes in the size or form.
- Map of south-western Iran
- Showing location of a number of sites that bracket the transition to early herding currently understudy by Smithsonian researchers. The site of Ganj Dareh in the highland homeland of wild goats shows the earliest secure evidence of goat domestication. Fully domestic goats later accompanied early pioneer populations as they moved into to arid lowland regions in Iran, like the region where the site of Ali Kosh is located. This site also contains evidence of early domestic goat but new Smithsonian research shows that the remains from the site are at least 500 years later than those from upland Ganj Dareh. (Map drawn by Marcia Bakry, Smithsonian Institution).
Click for larger map complete with legend.
Using this new technique, Zeder and Hesse have found the distinctive signature of modern domestic herds — selective killing of young males and prolonged female survival — at the 10,000-year-old archaeological site of Ganj Dareh in the highlands of Iran. By accurately dating fragments of animal bone, they determined that goat domestication first took place in this highland region, in an area within the natural geographic range of the species. People and their goats, over some 500 to 1000 years, then moved to arid lowland regions well outside the goats’ range. The management of herds, and the spread of food-producing technologies, offered a stable food supply to erstwhile hunters and opportunities for the human population to expand into new ecological areas, and grow in size.
The enormous ecological and human consequences — the spread of agricultural economies, the loss of biodiversity, and the development of cities — has become a fact of life ever since. By applying the Zeder and Hesse methods to other domesticated animal species in other regions of the world, we may yet learn why humans made a fundamental shift in lifestyle.