With National Science Foundation support Dr. Lawrence Kaplan will obtain thirty-three accelerator radiocarbon dates on early domesticated beans (genus Phaseolus) obtained from archaeological sites. Although indirect dates are available (based on charcoal and other organic materials associated with beans) very few direct determinations have been made and these vary significantly from the ages suggested by the indirect dates. The result is that very little is known about the timing and places of origin on this major New World domesticate. In conjunction with other chemical analyses, this project will permit archaeologists and biologists to understand the process of the domestication and spread of this food crop. The genus Paseolus includes five species of beans which were domesticated and widely used in the pre-Columbian New World. Together with corn and squash they formed the basis for much of the prehistoric diet over North, Middle and South America and were crucial for survival because they contain essential amino acids which are otherwise lacking. Given the presence of wild progenitors it is clear that domestication did take place in the New World but beyond that archaeological understanding is limited. The problem is of interest not only to biologists but also to archaeologists who wish to understand how complex chiefdoms developed. Until recently it was believed that the subsistence base necessary to support such a form of organization required a major domesticate. However recent work has suggested that such social complexity predates the domestication of corn and possibly beans as well. It seems likely that less well known and less productive crops played an important role. Dr. Kaplan's research will help to answer this question. This research is important for several reasons. It will provide data of interest to both biologists and anthropologists. It will also shed light on the origins of plant domestication and the development of complex societies.
