April 15, 2010

Eastern Africa is famous for its rich archaeological and paleontological sites as well as an abundance of wildlife and scenic beauty. It is now generally agreed among researchers that Kenya, and the eastern African region in general, form the “cradle of humankind.” It was in this region that the first steps were taken towards the development of the technologies and economic life-ways we enjoy today. Current knowledge about these developments, especially during the more recent periods, is patchy, most of the research having been conducted in a small part of the region within the narrow corridor defined by the Rift Valley. The areas to the west and east of the Rift largely remain unexplored.

To redress this geographical and chronological imbalance, Kathleen Ryan and an international team of colleagues, with National Science Foundation support, are focussing on the Laikipia Plateau to the east, overlooking the Rift Valley. They are concentrating on the more recent period of transition from the Later Stone Age (LSA) to the Pastoral Neolithic (PN) 4,000 to 5,000 years ago, when the first cattle herding groups entered Laikipia and interacted with the indigenous hunter-gatherers. Until recent decades, surprisingly little research had been conducted on the origins and spread of cattle herding in Africa. Although cattle domestication is believed to have occurred in Africa roughly 9,000 years ago, cattle pastoralism in East Africa began several millennia later, between 4,000 and 5,000 years ago. when the first cattle herding groups moved south into what is now Kenya. This period of transition–when indigenous hunter-gatherers and cattle herders first interacted in Laikipia–is the main focus of the investigations. When did these cattle herders reach Laikipia? What impact did they have on the lifestyle of the indigenous hunter-gatherers? As a pivotal part of the study, the team will work to identify the beginnings of widespread cow milk consumption in Laikipia, thus contributing to current discussions about the genetic basis in some modern African populations for lactose tolerance in adults–a significant evolutionary survival advantage and something generally not true of adult populations in other parts of the world.

In Africa today, cattle pastoralism and dairy farming remain principal livelihoods for millions of people, integrated into most aspects of cultural life. In recent years, harsh and unpredictable climate fluctuations in East Africa–possible signs of global warming–have affected the region’s pastoralists, and threaten their long-term ability to continue their semi-nomadic way of life.