Eastern Africa’s Earliest Livestock Herders Still Kept Hunting and Gathering

Study published in PNAS reveals this continued for centuries and the dietary variability may have helped them adapt to a tough and changing climate

STONY BROOK, NY, June 2, 2026 - An international team of researchers has discovered remarkable dietary variation among eastern Africa's first pastoralists - people who raised and consumed livestock and their products. Early herders living around Lake Turkana 5,000-4,000 years ago made highly individualized dietary choices, including fish, wild animals, and wild plants alongside livestock products. These findings, explained in a paper published in the Proceedings of the National Academy of Sciences, challenges the idea that once ancient peoples began producing their own food, their dietary choices became narrower and more standardized.

The authors, including senior author Elisabeth Hildebrand, PhD, Associate Professor of Anthropology at Stony Brook University, determined what these individuals in eastern Africa ate by analyzing chemical clues locked in ancient human teeth and bones. These clues come from stable isotopes-natural markers in teeth that reflect what a person ate while the tooth was forming. In simple terms, teeth keep a long-term record of diet, like a fossilized food diary.

"The isotopic record is fascinating because it can reveal individual to individual variation, even among people buried at a single site," says Dr. Hildebrand, a co-author who co-directed excavations at several sites on the west side of Lake Turkana in Kenya. "This kind of information goes beyond what one can discern from the animal bones left at a site after human consumption."

More than four millennia after eastern Africa's first pastoralists, domestic cattle in the Turkana region today.
Credit: Katherine Grillo

The researchers analyzed isotopic signatures on bone or tooth samples from more than 100 people who lived between about 9,500 and 200 years ago in Kenya and Tanzania. The study combines new samples with existing data, some generated decades ago and through other research efforts such as radiocarbon dating. The largest study of its kind in eastern Africa, this integrated dataset compares fishers and foragers who lived prior to the arrival of livestock to early herders and later pastoralists who lived after livestock had become central to daily life.

While previous isotopic work has explored this topic, this study provided a key missing piece - direct evidence from the earliest herders who lived in Kenya's Turkana Basin 5,000 years ago.

"The Turkana Basin has one of the most incredible mortuary archaeological records in Africa," says Elizabeth Sawchuk, PhD, the study's lead bioarchaeologist from the Cleveland Museum of Natural History and a Research Assistant Professor and former Postdoc at Stony Brook. "Based on our excavations of both fisher-forager and early herder cemeteries around the lake, we were able to directly assess the impact of the transition to food production on human diets," explains Dr. Sawchuk.

The results confirmed the team's suspicions.

"Early herders didn't put all their eggs in one basket," says geochemist Dr. Kendra Chritz, lead author and Assistant Professor at the University of British Columbia's Department of Earth, Ocean and Atmospheric Sciences. "They were keeping livestock, but they were also still fishing and hunting and gathering. Their diets were incredibly varied."

This diverse strategy to acquiring food may have given early African herders flexibility amid a rapidly changing climate, the authors suggest. While noting that dynamic climates have posed challenges throughout human history, they emphasize that early pastoralists lived in a time of dramatic reductions in rainfall, when Lake Turkana shrunk by 50 percent and local vegetation became more arid-adapted. Understanding how people coped with change and uncertainty can shed light on how we can adapt to climate stress today. It also reminds us that human diets were never one-size-fits-all. Variety was the norm, not the exception.

View of Lothagam North Pillar Site, a communal cemetery near Lake Turkana built by eastern Africa's first pastoralists.
Credit: Elisabeth Hildebrand

The authors say that the most unusual finding came from the earliest herders, who lived around Lake Turkana 5,000 years ago. Their tooth records showed huge variation from person to person. Some ate foods linked to grass-eating animals, such as cattle. Others relied much more on fish or wild animals. Many did both.

"It's clear that fisher-foragers followed dietary strategies that were situationally specific, or even personalized," explains Dr. Hildebrand. "And the first pastoralists maintained this very individualized approach, even as they began constructing communal cemeteries that involved large social networks connecting hundreds of people."

The study shows that people adopted more standardized diets more than 1,000 years later, after herding spread across eastern Africa. Pastoralists in Central Kenya and Tanzania had isotopic values that were more uniform. More stable environmental conditions may have allowed for this.

The team also looked at residues left behind in ancient ceramic cooking pots. These fatty traces-basically food stains locked into clay-reveal what was cooked long ago. Some pots from early herders contained fats from animals, but only rarely showed signs of dairy foods like milk. That suggests livestock were important, but not the mainstay of meals.

"This research is a testament to what becomes possible when Kenyan institutions are genuine partners in global science-not just sites of data collection, but active contributors to knowledge production," adds Dr. Emmanuel Ndiema, co-author on the study and head of Earth Sciences at the National Museums of Kenya. "The findings illuminate the ingenuity and resilience of the people who shaped this landscape thousands of years ago, and we are proud that Kenya's heritage is at the centre of this story."