A significant reduction in the presence of large animals approximately 200,000 years ago could have prompted ancient humans to shift away from cumbersome stone tools, embracing lighter toolkits for hunting smaller prey. This hypothesis, emerging from new research, lends support to the idea that adapting to smaller game may have contributed to the enhancement of our ancestors’ cognitive abilities.
For over a million years, various early human species consistently employed large stone implements, including axes, cleavers, scrapers, and stone balls. Archaeological evidence suggests these tools were primarily used for the subduing and processing of massive herbivorous animals, or megaherbivores. These ancient creatures included now-extinct relatives of modern elephants, hippopotamuses, and rhinos.
Subsequently, between 400,000 and 200,000 years ago, a transition began to take place. More delicate, sophisticated tools started appearing in the archaeological record, coexisting with the older, heavier tools. It was during this period that our own species, Homo sapiens, first emerged.
Around 200,000 years ago, a notable disappearance of heavy tools from archaeological sites occurred in the Levant. Concurrently, there was a discernible increase in the prevalence of small, lightweight stone toolkits. These lighter tools, such as blades and precision scrapers, were not only more numerous but also exhibited greater sophistication and variety.
This technological shift now appears to be linked to a substantial decline in large herbivorous mammals during that era, a decline possibly driven by overhunting. This connection has been investigated by Vlad Litov at Tel Aviv University, Israel, and his research collaborators.
Analyzing Archaeological Evidence in the Levant
The research team meticulously catalogued archaeological findings from 47 identified sites across the Levant, spanning the Paleolithic period, which lasted from approximately 3.3 million to 12,000 years ago. By cross-referencing dated stone tool artifacts with animal remains recovered from each site, an interesting pattern began to emerge.
The study revealed that following the 200,000-year mark, coinciding with the disappearance of heavy-duty technologies from the archaeological record, there was a significant decrease in the relative abundance, number of specimens, and contribution to biomass of megaherbivores weighing over 1000 kilograms. Simultaneously, the presence and availability of smaller prey species increased, paralleled by a rise in the number of more complex small tools.
Further strengthening the link between stone tool technology and prey types, the researchers noted that prior studies have indicated the persistence of heavy-duty tools until around 50,000 years ago in other regions. This persistence occurred in areas where large prey remained accessible, such as in southern China.
Rethinking the Driving Force Behind Technological Advancement
Previous theories posited that the observed shift in tool technology was likely a consequence of humans already possessing greater intelligence and innovation. These theories often attributed this advancement to unspecified evolutionary pressures or beneficial genetic mutations.
However, Litov and his team propose an alternative explanation, building on their prior research. They suggest that a growing reliance on smaller prey actively drove the evolution of larger brains in modern humans. “As megaherbivores declined, humans increasingly relied on smaller prey, which required different hunting strategies, more flexible planning, the use of lighter and more complex toolkits,” Litov explained. “These challenges selected for enhanced cognitive abilities, meaning cognition evolved as part of this new adaptive system rather than driving it from the outset.”
Some experts offer a more nuanced perspective. Ceri Shipton from University College London suggests that the story may involve more than just prey size. He points to studies indicating cognitive changes and more sophisticated planning already underway in the Middle Paleolithic, with some emerging evidence of mass hunting of medium-sized ungulates like horses and bison.
Nicolas Teyssandier of the French National Centre for Scientific Research also expresses some reservations. “If humans adapted to new fauna, this reflects adaptation rather than pure intelligence,” he commented. “It was equally intelligent to produce and select heavy-duty technologies for hunting and consuming large megaherbivores.”
The Evolutionary Impact of Dietary Shifts
Litov acknowledges that earlier research, including his own, points to significant cognitive capabilities present even in early stages of human evolution, particularly in Homo erectus, which appeared approximately two million years ago. Nevertheless, he maintains that the transition from targeting large game to smaller animals had a profound impact on humans.
He elaborated that a single carcass from an ancient elephant could have sustained a group of around 35 hunter-gatherers for an extended period. The disappearance of such calorie-rich resources would necessitate turning to smaller prey, resulting in a lower caloric return per animal. “From an energetic standpoint, they had to acquire dozens of smaller ungulates, such as fallow deer, to compensate for the loss of a single elephant,” Litov stated.
This dietary shift, he argues, could have spurred a range of cognitive and behavioral changes. These might include more coordinated hunting of elusive prey, the development of more intricate technologies, and increased social cooperation and planning. “These demands may have contributed to the selection for larger brains in later species, including Neanderthals and Homo sapiens,” he concluded.
Shipton offered his personal view: “My personal view is that a decline in the large prey that hominins were used to may have increased competition between groups. In reality, it was probably an iterative process where decline in larger prey drove cognitive change, which, in turn, enabled access to smaller prey.”