Before Agriculture: How Prehistoric Humans Milled Starchy Plants 780,000 Years Ago

Redacción HC
07/01/2025

The image of prehistoric human diets has long been dominated by meat—hunting scenes, bone tools, and protein-heavy meals. But new archaeological evidence from a Middle Pleistocene site in Israel challenges that narrative. A groundbreaking study published in Proceedings of the National Academy of Sciences (PNAS) reveals that early humans were grinding and processing starchy plant foods nearly 800,000 years ago, long before the advent of agriculture.

This research not only expands our understanding of ancient diets—it rewrites the timeline of cognitive and technological complexity in human evolution.

Early Culinary Technology: Stone Tools as Primitive Food Processors

The study, led by researchers from Bar-Ilan University, Leiden University, and the Hebrew University of Jerusalem, focused on eight Acheulian stone tools (hammerstones and anvils) recovered from the Gesher Benot Ya’aqov site in the Jordan Valley, Israel. These tools date back approximately 780,000 years—placing them in the early Middle Pleistocene.

Using microscopic analysis, the team identified more than 650 starch granules embedded on the surfaces of these tools. The granules corresponded to a range of plant species, including:

• Acorns
• Wild grasses and cereals
• Water chestnuts
• Aquatic rhizomes
• Legumes

The diversity of plant types—and their habitats—suggests that early humans were actively selecting, harvesting, and processing plants from both terrestrial and aquatic environments, demonstrating a deep knowledge of local ecosystems.

The Cognitive Leap: Planning, Dexterity, and Diet

Processing starchy plants like acorns or roots is no simple task. It requires:

• Recognizing which plants are edible and energy-rich
• Gathering them at the right time of year
• Using tools to crack, grind, or crush their tough exteriors

The presence of specialized tools for such tasks implies intentional planning and cooperation. According to the study’s authors, this behavior reflects “advanced motor skills, group coordination, and dietary innovation”—traits that are hallmarks of human evolution.

“These early humans weren’t just scavenging—they were cooking up a strategy,” said co-author Amanda G. Henry of Leiden University. “Starchy plants likely played a crucial role in fueling larger brains and longer lifespans.”

Redefining Human Diets: It Wasn’t All About Meat

Historically, archaeological research has prioritized animal remains and hunting tools, which preserve better over time. Plant foods, by contrast, are perishable and often invisible without advanced analysis techniques.

This new study shifts the spotlight toward plants—especially those rich in complex carbohydrates—as vital energy sources for early humans. Rather than being occasional supplements, these foods may have been core staples.

Complementing earlier discoveries at the same site—such as charcoal, seeds, and phytoliths—this new microstarch evidence offers the first direct confirmation that hominins actively processed plants for consumption on-site.

Broader Implications: From Prehistoric Tools to Modern Knowledge

The findings have practical applications for museum exhibitions and science education, providing vivid examples of how ancient humans engaged with their environments in complex ways. They also resonate with indigenous plant-gathering traditions still practiced today in parts of Africa, Asia, and Latin America.

Furthermore, the study encourages a broader archaeological agenda:

• Conducting similar microresidue analyses at other Acheulian and pre-agricultural sites
• Exploring the caloric and nutritional impact of plant foods in human evolution
• Recognizing plant processing as a pre-agricultural innovation, not merely a byproduct of farming

A New Lens on Our Ancestors

This discovery reframes the Acheulian toolkit—from weapons of survival to culinary instruments of adaptation. Long before grinding stones became common in farming societies, early humans were already investing time and effort into extracting calories from wild vegetation.

As Naama Goren-Inbar, one of the lead authors, noted: “We now have tangible proof that plant foods were processed with intention and skill long before agriculture.”

This insight offers a new lens through which to view human evolution—not merely as a story of hunting prowess, but as a saga of ingenuity, ecology, and the silent power of starch.

Topics of interest

History