This project contributes new data points for understanding terminal Pleistocene and Holocene hunter-gatherer adaptations to changing environmental conditions in an important, though understudied, region in eastern Africa – the semi-arid southern Horn. Recently, archaeologists and anthropologists have recognized greater global diversity in the ways hunter-gatherers lived and organized themselves in the past than originally thought. However, exactly where, when, and why new forager social and economic systems emerge is not well-known. This is particularly true in the tropics where seasonal fluctuations in resources are less marked, but large-scale environmental shifts can affect the abundance and diversity of plants and animals available to people over time. By examining long-term hunting and mobility patterns among foragers living in the semi-arid plains of southern Somalia during a period of marked rainfall instability, this project provides new perspectives on the flexibility and resilience of tropical hunter-gatherer lifeways to changing environmental conditions. As a result, findings from this study contribute new information for understanding the durability of foragers in less favorable African settings.

Traditionally, hunter-gatherers in arid tropical environments are presumed to live in small, highly mobile groups and acquire food on an encounter-basis. However, findings from this project suggest that under certain circumstances more sedentary lifeways and specialized hunting strategies can develop among equatorial foragers. New radiocarbon dates from the Guli Waabayo rock shelter in southern Somalia indicate that people regularly occupied the site between ~26,000-6,000 years ago. During this time, people focused their hunting efforts on a diversity of small game found on or around the productive inselberg environment surrounding the site. An emphasis on small animal hunting is unusual among arid-adapted hunter-gatherers in Africa and indicates a unique, localized subsistence strategy that allowed people to survive in a generally dry, unproductive landscape for thousands of years. Isotopic reconstructions of local rainfall patterns during the site’s occupation confirm significant climatic fluctuations between dry and wet, which would have altered the amount and distribution of animal resources over time. However, rather than change their hunting strategies, foragers at Guli Waabayo maintained a consistent subsistence strategy that focused on small, territorial animal species throughout. A commitment to resources found near the site indicates that small game hunting was a particularly useful survival strategy during Pleistocene arid periods as well as Holocene wet periods. Evidence of specialized dik-dik net-hunting practices suggests that small mammal hunting may have been socially important to foragers as well, particularly during the wet Early Holocene when resources were more abundant throughout the region.

Findings from this research provide the first clear evidence of repeated hunter-gatherer occupation in southern Somalia during both the hyper-arid Last Glacial Maximum ca. 26,000-15,000 years ago and the wet African Humid Period ca. 15,000-6,000 years ago. This offers a rare window into human existence during two critical climatic episodes in a part of Africa that is key for understanding the biological and cultural evolution of our species. Evidence of long-term small game hunting for ~20,000 years suggests a unique pattern of hunter-gatherer behavior that would have influenced and shaped the trajectories of later food producing complex societies in the Horn. By investigating artifacts from Somalia that were excavated and exported to the U.S. in the 1980s, this project brings to fruition an NSF grant awarded to S. Brandt in the 1980s and encourages positive scientific attention on a war-torn, often overlooked part of the Horn of Africa through a series of forthcoming peer-reviewed publications. Reported findings from this research will be compared to similar data from contemporaneous hunter-gatherer sites in the wetter Lake Victoria Basin in Uganda to examine forager decision-making and behavior in two different eastern African ecotones during the terminal Pleistocene and Holocene. This comparative approach will yield new perspectives on hunter-gatherer variability in tropical environments broadly and may have implications for understanding long-term patterns of social and economic change among African societies that helped shape the biologically and culturally diverse landscape we see in the region today.

Last Modified: 12/13/2019
Modified by: Mica B Jones