For archaeologists, a handful of dirt can be a treasure trove. Plant fossils, often overlooked, hold secrets about ancient diets, farming practices, and even leisure activities. Now, a groundbreaking discovery in Kenya is rewriting the narrative of East Africa’s agricultural beginnings.
An international team unearthed 2,300-year-old plant remains at the Kakapel Rockshelter, a 9,000-year-old archaeological marvel nestled near Kenya’s border with Uganda. This discovery, detailed in a recent study published in Proceedings of the Royal Society B, represents the earliest evidence of plant farming in the region.
“This is where human evolution occurred,” said Dr. Natalie Mueller, a co-author of the study and paleoethnobotanist at Washington University in St. Louis. “We know hunting and gathering thrived here, but there was no archaeological evidence about the specific plants these communities consumed. If we can glean such information from this assemblage, it’s a significant contribution.”
A Window into Millennia
The Kakapel Rockshelter is a unique site, offering a glimpse into millennia of human habitation. Layers upon layers of artifacts speak to the diverse communities that thrived there. “It’s one of the few sites in the region showcasing such a long and varied history of human settlement,” remarked study co-author Dr. Steven T. Goldstein, an anthropological archaeologist at the University of Pittsburgh.
Dr. Mueller, a seasoned practitioner of a separation technique called flotation, meticulously isolated remnants of wild and domesticated plants from ash and debris found in an excavated hearth. This method, while used elsewhere by Dr. Mueller, is not as prevalent in East Africa due to water scarcity.
Radiocarbon dating placed the arrival of the cowpea, or black-eyed pea, in East Africa around 2,300 years ago, coinciding with the region’s early cattle domestication. These finds suggest a gradual introduction of crops from other parts of the continent.
“The sheer volume of plant remains, particularly domesticated crops, was astonishing,” said Dr. Mueller. “This challenges the stereotypical view of African agriculture as static and unchanging. The past reveals a rich tapestry of diverse and adaptable farming systems in the region.”
The Intriguing Case of the Pea
The cowpea find marks the earliest documented instance of a domesticated crop, potentially signifying the dawn of farming itself, in East Africa. Interestingly, cowpeas are believed to have originated in West Africa. The team speculates that their arrival in the Lake Victoria basin might coincide with the Bantu migrations from Central Africa.
“Our findings at Kakapel provide the earliest evidence of domesticated crops in East Africa, highlighting the dynamic interplay between local herders and incoming Bantu-speaking farmers,” explained Dr. Emmanuel Ndiema, co-author and senior research scientist at the National Museums of Kenya.
Beyond the Cowpea
The team also unearthed evidence of grain sorghum, arriving from the northeast at least 1,000 years ago, and finger millet seeds, a grain native to East Africa and still cherished by communities near Kakapel today. However, the most perplexing discovery was a single, burnt but intact, field pea.
“Previously, peas weren’t considered part of early agriculture in this region,” explained Dr. Mueller. “The standard peas consumed in North America were domesticated in the Near East, likely reaching East Africa via the Nile through Sudan, similar to sorghum. But there’s another story – the Abyssinian pea, domesticated independently in Ethiopia. Our sample could be either!”
Building a Legacy
Several plant remains defied identification due to the limited reference collections in the area. The team is currently building a comprehensive comparative plant collection for Tanzania. This data, along with the study’s findings, will be invaluable to researchers in plant science, genetics, historical linguistics, African history, and domestication studies.
“Our work underscores the constant evolution of African farming practices,” concluded Dr. Mueller. “Prior to European colonialism, local communities thrived due to their flexibility and decision-making regarding food security. This adaptability remains crucial in many places today.”
The unearthed evidence at Kakapel Rockshelter is not just about ancient peas; it’s about rewriting the story of human ingenuity and agricultural development in East Africa.