This revelation emerges from an expansive study led by researchers at the University of British Columbia, published in the prestigious Proceedings of the National Academy of Sciences. The investigation utilized stable isotope analysis on dental enamel from over a hundred individuals dating from approximately 9,500 to 200 years ago, excavated from archaeological sites around Lake Turkana, northern Kenya, and regions in Tanzania. Stable isotopes serve as biochemical signatures locked within tooth enamel, encoding information about an individual’s diet during tooth formation and providing an unparalleled window into ancient subsistence behaviors across time and individuals.

One of the most striking findings is the extraordinary dietary variability among early herders who lived roughly 5,000 years ago during a critical transitional epoch marked by abrupt climate shifts and the establishment of pastoralism in the region. While domesticated livestock such as cattle, sheep, and goats were present, individuals’ isotopic profiles varied significantly—some primarily consumed animal products derived from grassland grazers, others depended heavily on aquatic resources such as fish, and many incorporated a mix of wild game and plant foods. This heterogeneity suggests dietary flexibility rather than binary food production models, debunking previous assumptions that pastoralism immediately supplanted foraging diets.

Lead geochemist Dr. Kendra Chritz interprets this dietary complexity as an adaptive hedge against environmental unpredictability, especially given the rapid desiccation and falling lake levels across Lake Turkana during the mid-Holocene. As pastures fluctuated with irregular rainfall, early herders diversified their food procurement to mitigate the risk of livestock losses. This multifaceted strategy underscores the intricate relationship between human cultural decisions and ecological dynamics, illuminating how resilience was biologically and socially engineered through dietary breadth.

Significantly, the ancient culinary repertoire is further elucidated by ceramic residue analysis, a method that detects lipid biomarkers embedded within prehistoric cooking vessels. These fatty residues reveal that while animal fats were cooked, the presence of dairy biomarkers was rare in early pastoral contexts. This nuanced dietary evidence aligns with isotopic data, reinforcing the idea that despite the presence of domesticated livestock, milk and dairy products were not central staples in their diet initially. The integration of ceramic residue study thus complements isotopic findings, offering a holistic perspective on what was consumed and prepared, shedding light on nuanced early pastoral food economies.

This sustained dietary mosaic persisted for well over a millennium before a noticeable narrowing of food sources occurred among later pastoralists in southern Kenya and northern Tanzania. Isotopic data from these later populations indicate a stronger reliance on livestock products, suggestive of ecological stabilization and the establishment of more specialized pastoral economies. This progression from dietary diversity to specialization encapsulates how cultural practices evolve in concert with environmental conditions, providing a temporal narrative of human adaptation and subsistence transitions.

Anthropologists and archaeologists involved in the study emphasize that these findings challenge reductive models where food production equates with monocultural diets. Instead, variability and individual choice stood as defining features of early food-producing societies in eastern Africa. Dr. Elisabeth Hildebrand highlights that even within individual sites and communities, significant person-to-person dietary differences existed, comparable to those observed among hunter-gatherers. This diversity signals personalized or situational dietary strategies adapted to complex social networks and fluctuating micro-environments.

The study also revalidates the African Humid Period’s role in shaping dietary patterns. Populations inhabiting the region during this wetter interval similarly exhibited wide dietary ranges, leveraging abundant aquatic and terrestrial resources. The continuity of such strategies into the pastoral era indicates cultural persistence despite transformative subsistence innovations. Such insights provide compelling evidence that early pastoralist diets were not static but dynamically responsive to ecological and cultural pressures.

Pottery residue data not only informs on consumed animal products but also reveals information about the vegetation ingested by domesticated herbivores. These indirect clues about pasture composition contribute to reconstructing paleoenvironmental conditions. Co-author Dr. Katherine Grillo remarks that integrating isotopic analysis of human remains with ceramic lipid residues fosters a finely resolved dialogue between ancient environmental changes and cultural adaptations, enhancing the interpretive power of archaeological science.

The implications of this research extend far beyond reconstructing ancient diets. Understanding how prehistoric societies maintained resilience amid climatic stress through diversified food economies may yield insights into modern strategies for coping with environmental uncertainty. As global climate volatility intensifies today, revisiting the adaptive versatility of early pastoralists underscores the enduring significance of dietary flexibility and resource plurality in human survival.

Moreover, this work exemplifies the importance of collaborative partnerships between Kenyan institutions and international researchers. Dr. Emmanuel Ndiema, a co-author and head of Earth Sciences at the National Museums of Kenya, highlights that such joint ventures ensure that local heritage and knowledge systems are integral to global scientific discourse. This synergy enriches both empirical data collection and the cultural narrative surrounding Africa’s formative human histories.

In summary, this landmark study reveals that eastern Africa’s initial embrace of pastoralism was not marked by immediate dietary specialization but by enduring diversity and multi-resource reliance. By leveraging biochemical analyses of teeth and ancient ceramics, it challenges long-standing paradigms and paints a complex portrait of ancient human resilience, cultural ingenuity, and ecological adaptation in one of the world’s most dynamic environmental contexts.

Subject of Research: Dietary variability and subsistence strategies among early pastoralists in eastern Africa.

Article Title: Isotopic evidence for dietary variability among eastern Africa’s first pastoralists.

News Publication Date: 18-May-2026.

Web References:

• DOI: 10.1073/pnas.2532741123

Keywords: Eastern Africa, pastoralism, diet, stable isotope analysis, ceramic residue analysis, Lake Turkana, early herders, subsistence strategies, environmental adaptation, archaeological chemistry, African Humid Period, human resilience.

The site itself boasts a raised ridge field system dating from roughly the 10th century through the 1600s, much of which astonishingly remains intact. These fields comprise a series of clustered ridged garden beds, varying in height from four to twelve inches. Constructed and maintained by ancestors of the Menominee Indian Tribe of Wisconsin, these ridges were instrumental for cultivating staples such as corn, beans, squash, and various other plants integral to their diet and culture. The scale and preservation of this agricultural landscape challenge long-standing assumptions about prehistoric subsistence strategies in the region.

Published in the prestigious journal Science, this new study dramatically increases previous estimates of the extent of indigenous agriculture in eastern North America by a factor of ten. Madeleine McLeester, lead author and assistant professor of anthropology at Dartmouth, emphasizes the transformative impact of these findings on our understanding of agriculture on both local and global scales. The sheer size of the farming system suggests a level of social organization and labor investment typically associated with large, state-level societies, contradicting existing beliefs about the small, egalitarian communities historically thought to inhabit this region.

Covering approximately 330 acres, the researchers utilized cutting-edge drone-based lidar technology to penetrate the dense forests and generate a highly detailed topographical map of the ancient fields. This technique employs laser pulses to create a three-dimensional “point cloud” of the landscape, which can then be filtered to remove vegetation data and reveal man-made features beneath the canopy. The high-resolution data unveiled an intricate matrix of parallel ridges stretching across the site in quilt-like patterns, reflecting the adaptive strategies and spatial organization of indigenous farmers rather than simple environmental constraints.

Senior author Jesse Casana, a professor of anthropology renowned for his expertise in remote sensing, underscores the revolutionary nature of drone lidar in archaeological research. Unlike traditional aerial lidar, which often lacks the resolution necessary to detect subtle features, drone-mounted systems offer unprecedented detail, enabling archaeologists to reveal hidden anthropogenic landscapes within heavily vegetated environments where conventional imaging falls short.

Beyond the agricultural ridges, the lidar survey exposed a wealth of archaeological features, including a circular dance ring, a rectangular structure hypothesized to have been a colonial trading post, remnants of two 19th-century logging camps, and multiple burial mounds—some previously unknown or believed destroyed. These discoveries highlight a complex cultural landscape reflecting centuries of human activity, from ritual gatherings to economic exchanges, deeply intertwined with the natural environment.

In August 2023, complementary archaeological excavations targeted three of the raised ridges, sourced at varying distances from the Menominee River. Radiocarbon dating of charcoal samples found within soil strata indicated that these ridges were continuously maintained and periodically rebuilt over a 600-year span, starting around the year 1000, coincident with the Late Woodland period. This continuity suggests not only the longevity of these farming practices but also the resilience and adaptation of the indigenous communities within this challenging ecosystem.

The excavations also yielded charcoal fragments, ceramic sherds, and other artifacts, implying a sophisticated system of soil enrichment and nutrient recycling involving domestic refuse and controlled burns. Charcoal and household waste likely served as compost additives, while incorporation of wetland soils would have improved moisture retention and fertility, optimizing conditions for crops like maize that were cultivated near the northern limits of their natural growth range. This evidence illustrates a deep ecological knowledge and manipulation of local environments by the ancestral Menominee.

The research team’s partnership with the Menominee Indian Tribe of Wisconsin was central to the study’s success, combining community collaboration with advanced scientific methods. Tribal historic preservation officers and consulting archaeologists worked alongside Dartmouth researchers, ensuring the ethical stewardship of culturally significant sites while expanding scholarly understanding of indigenous land use and sustainability practices.

Lidar technology’s contribution to this discovery cannot be overstated. In landscapes where dense forests obscure surface features, the ability to virtually "strip away" the canopy exposes archaeological formations that would otherwise remain invisible. This facilitates a holistic understanding of ancient land management and spatial organization, offering new perspectives on how indigenous peoples transformed and thrived within their environments.

The findings compel a reevaluation of the agricultural history of not only Michigan’s Upper Peninsula but potentially much of eastern North America. The existence of extensive raised-field farming systems suggests that precolonial deforestation and landscape modification were far more widespread than previously acknowledged. Consequently, current forest cover and soil conditions may only represent a fraction of the original anthropogenic environments shaped by indigenous agricultural practices over centuries.

Conclusions drawn from this research challenge entrenched paradigms about the scale and complexity of precontact Native American societies in the northern Midwest. They reveal a dynamic and organized community capable of engineering large-scale modifications to the land to secure food sustainability. This reshapes our understanding of the environmental legacy of these groups and underscores the intricate relationship between cultural practices and ecological contexts.

As the Dartmouth team continues their collaborative work with the Menominee tribe, plans are underway for expanded surveying and excavation aimed at uncovering additional ancestral villages. These endeavors promise to further illuminate the social, economic, and spiritual dimensions of indigenous life in this region prior to European colonization.

Through a combination of ancient technologies, modern remote sensing, and respectful tribal partnership, this study opens a remarkable window into indigenous ingenuity, resilience, and land stewardship critical for redefining North America’s precolonial past. The Sixty Islands site stands as a testament to the enduring legacy of the Menominee and provides a powerful reminder of the continent’s deep, vibrant human history hidden just beneath our feet.

Subject of Research:
Not applicable

Article Title:
Archaeological Evidence of Intensive Indigenous Farming in Michigan’s Upper Peninsula, USA

News Publication Date:
5-Jun-2025

Web References:
https://www.science.org/doi/10.1126/science.ads1643

References:
10.1126/science.ads1643

Image Credits:
Photo by Madeleine McLeester

Keywords:
Agriculture, Archaeological sites, Historical archaeology, Food production, Social sciences, Cultural anthropology, Crops, Maize, Food crops, Remote sensing, Lidar, Ethnicity, Land use, Cropland, Land management, Human geography