A new study published in the journal, Proceedings of the National Academy of Sciences (PNAS), challenges long-held assumptions about the diets of early pastoralists—people who lived by herding cattle and other animals—in eastern Africa.
Researchers previously believed that herders shifted their diet to rely heavily on livestock after domesticated animals arrived in the region. However, the study reveals that Africa’s earliest herders ate varied diets of fish, wild animals, and gathered foods alongside livestock.
The study analyzed clues held within ancient human teeth and bones. The remains came from over 100 individuals, including the earliest herders who lived in Kenya’s Lake Turkana Basin 5000 years ago and who had not previously been studied. These individuals were excavated by the Cleveland Museum of Natural History’s Curator of Human Evolution, Dr. Elizabeth Sawchuk, who has been working around Lake Turkana for almost 15 years.
Filling a Gap in Archaeological Evidence
Dr. Sawchuk’s work in the Turkana Basin began in 2012 during her doctorate program when she joined the Later Prehistory of West Turkana team, excavating megalithic cemeteries left by these early herders. Since then, she has graduated to lead the team’s bioarcheological research as co-principal investigator. The remains recovered by Dr. Sawchuk and her team played a key role in the study, helping researchers examine some of eastern Africa’s earliest herding communities.
According to Dr. Sawchuk, who was the second author and lead bioarchaeologist on the study, “Archaeologists have been studying how diets changed with food production for decades, but previous work in eastern Africa was only able to compare ancient hunter-gatherers with Pastoral Neolithic herders who lived about 3,000 years ago. What we really needed were the people who first adopted this strategy 2,000 years earlier.” The remains recovered by Dr. Sawchuk and her teams helped fill a major gap in the archaeological record, offering rare insight into some of eastern Africa’s earliest herding communities.
How Scientists Study Ancient Food Systems
Teeth are often used to determine diets of ancient peoples because they are extremely durable and long-lasting and also contain chemical traces—called isotopes—that reveal what these individuals ate during their lifetimes. Tooth enamel doesn’t change after forming, which means its isotopic makeup remains the same throughout an individual’s life. These chemical signatures can reveal what people ate and the environments they lived in during childhood.
The study examined teeth from individuals who lived between about 9,500 and 200 years ago in Kenya and Tanzania. They represent diverse hunter-gatherers who sustained themselves on wild foods, as well as food producers who lived by herding and farming. Domesticated cattle, sheep, and goats first spread from the Sahara into eastern Africa 5000 years ago at the end of the African Humid Period, giving rise to diverse herding cultures throughout the Great Rift Valley. Later, in the Iron Age, people began to farm following additional movements of people and crops primarily from western Africa.
The individuals Dr. Sawchuk excavated lived as hunter-fisher-gatherers and early pastoralists around Lake Turkana between 9,500 and 5,000 years ago, capturing the very beginnings of the transition of food production amidst global environmental change that caused Lake Turkana to shrink by approximately 50%. Understanding differences in diets across these groups is an important window into their social organization and reveals how these communities responded to big changes in climate, migration, and economy over the past 10,000 years.
Herding Didn’t Change Diets Overnight
The study found that while the earliest herders integrated meat and potentially dairy from domesticated animals into their diets, they still relied heavily on fish and other wild foods, making their diets more similar to earlier fisher-foragers in the area. In fact, diets varied widely between individuals even in the same communities—much like diets in contemporary times. This reveals that humans have had preferences and individualized diets for thousands of years.
“This research shows that producing food from domesticated animals and plants—one of the most important innovations in human history—did not necessarily revolutionize people’s diets and economy right away,” shared Dr. Sawchuk. In fact, people in the Turkana Basin didn’t become dependent on their livestock until 2,000 years later. This was likely due to changing rainfall patterns and expanding grasslands. Early pastoralists couldn’t depend exclusively on domesticated animals, necessitating a broader approach to diet that incorporated other dependable local resources like fish.
Local communities also dealt with changing social and cultural relationships as this transition occurred. As migrant herders abandoned the drying Sahara and encountered local fisher-foragers around a shrinking Lake Turkana, these groups likely formed new relationships to negotiate land and resources. This led to the development of a mixed herding and fishing economy around the lake as well as new cultural traditions, including the construction of elaborate megalithic cemeteries. This flexible approach to diet, land, and resource use remains a mainstay of pastoralism today, making it one of the most adaptive economic strategies across dryland eastern Africa.
Rethinking the Story of Food Production
This study not only reveals new information about eastern Africa’s earliest herders but also reshapes long-held assumptions about how humans adapted to major environmental and cultural change. Rather than quickly abandoning fishing, hunting, and gathering after livestock arrived in the region, ancient communities developed flexible survival strategies that shifted alongside changing landscapes, climates, and resources.
Those findings carry broader implications beyond archaeology. They suggest that human adaptation is rarely immediate or straightforward. Instead, communities respond creatively to uncertainty, blending older traditions with emerging technologies and ways of life.
“This research matters because millions of people in eastern Africa today are still herders, including our community partners around Lake Turkana,” Dr. Sawchuk added. “As contemporary climate change threatens this way of life, we can look to the past to understand how pastoralism first developed in this part of the world, and what makes it so flexible and resilient.”
The Importance of Fieldwork
As Dr. Sawchuk continues her fieldwork in Kenya, studies like this continue to deepen our understanding of how ancient communities navigated environmental instability and social change, and how resilience shaped human survival over thousands of years.
These findings also highlight the importance of long-term archaeological research and collaboration. Over a decade of excavation work and analysis went into recovering the samples that became a critical piece of the study, demonstrating how fieldwork can continue shaping scientific discoveries long after the excavations end. Other individuals in the study were excavated many decades ago and are now curated at the National Museums of Kenya, emphasizing the role museums play in preserving human history and driving new research. This study provides a model for combining new and existing datasets to answer big questions in archaeology and human evolution, even leveraging data produced through other research efforts such as ancient DNA and radiocarbon dating. This work was led by Dr. Kendra Chritz at the University of British Columbia and was coauthored by an international team of eighteen scientists from Canada, the USA, Kenya, and the United Kingdom.
Rather than telling a simple story of one lifestyle replacing another, the study reveals a more human picture of the past—one defined by flexibility, resilience, and survival in a changing world. To learn more, you can read the full study or stop by the Museum to learn more about the evolving story of human history, adaptation, and survival.
