Why early humans radically changed their toolkits 200,000 years ago

A decline in the number of giant animals 200,000 years ago may have forced ancient humans to abandon sturdy stone tools in favor of lightweight toolboxes for hunting smaller animals. That’s according to a new study that supports the idea that switching to smaller prey could have made our ancestors more intelligent.

For over a million years, several early human species used similar types of heavy stone tools, such as axes, cleavers, scrapers, and stone balls. Evidence suggests that such tools were used to kill and dismember massive herbivorous, or megaherbivorous, prey, including now-extinct relatives of elephants, hippos and rhinos.

Then, 400,000 to 200,000 years ago, smaller, more sophisticated tools began to appear alongside heavy tools. Our species, Homo sapiens, appeared in the middle of this period.

Around 200,000 years ago, heavy tools curiously disappeared from the archaeological record of the Levant. At the same time, there has been an increase in the number of small, lightweight stone toolkits, including more sophisticated and diverse precision blades and scrapers.

Now, Vlad Litov of Tel Aviv University, Israel, and his colleagues have found a link between the apparent technological change and a dramatic decline in the era’s large herbivorous mammals, which may have been wiped out by overhunting.

The researchers cataloged archaeological finds from 47 known sites in the Levant throughout the Paleolithic, which lasted from about 3.3 million to 12,000 years ago. When they cross-referenced all the dated stone objects with the animal remains from each site, an intriguing pattern emerged.

The team found that 200,000 years ago, when heavy technologies disappeared from the record, there was a significant decline in the relative abundance, number of specimens and biomass contribution of megaherbivores weighing more than 1,000 kilograms. At the same time, the presence and availability of smaller prey has increased alongside the number of small, more sophisticated tools.

Strengthening the link between stone tools and prey types, the team also points out that previous studies have shown that heavy tools persisted until around 50,000 years ago in other regions where large prey remained available, such as southern China.

Previous ideas suggested that technological change likely occurred because humans were already smarter and more innovative, perhaps due to unknown evolutionary pressures and advantageous genetic mutations. But Litov and his team think the results support a different idea than they previously proposed: that reliance on smaller prey was behind the evolution of big brains in modern humans.

“As megaherbivores declined, humans relied more and more on smaller prey, which required different hunting strategies, more flexible planning, and the use of lighter, more complex toolkits,” says Litov. “These challenges were selected to improve cognitive abilities, meaning that cognition evolved as part of this new adaptive system rather than driving it from the start.”

“I would say it’s not just about prey size,” says Ceri Shipton of University College London. He says studies have shown that there were already cognitive changes and more sophisticated planning in the Middle Paleolithic, with tentative evidence of mass hunting of medium-sized ungulates, including horses and bison.

Nicolas Teyssandier, from the National Center for Scientific Research, also has reservations. “If humans adapted to new wildlife, that reflects adaptation rather than pure intelligence,” he says. “It was equally smart to produce and select robust technologies to hunt and consume large megaherbivores.”

Litov acknowledges that his and other researchers’ previous work highlights high cognitive abilities already present in the early stages of human evolution, particularly in Homo erectusappeared about 2 million years ago. But he maintains that the shift from large to small prey had a profound effect on humans. A single ancient elephant carcass could have fed a band of around 35 hunter-gatherers for months. If these calorie-rich resources disappeared, the reliance on smaller prey would lead to lower yields per animal, he says.

“From an energy point of view, they had to acquire dozens of smaller ungulates, like deer, to compensate for the loss of a single elephant,” says Litov. This could have led to a series of cognitive and behavioral changes, including increased coordinated hunting of elusive prey, the development of more complex 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 said.

“My personal view is that a decline in the large prey that hominids were accustomed to may have increased competition between groups,” says Shipton. “In reality, this was likely an iterative process in which the decline of larger prey led to cognitive change, which, in turn, allowed access to smaller prey.”

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