The Engineering Secrets of Ancient Stone Tools: Archaeologists Reveal Stone Age Survival Wisdom

In the latest episode, we speak with Dr. Ariel "Arik" Malinsky-Buller, a Paleolithic archaeologist at the Hebrew University, about how ancient stone tools reveal how people engineered, traveled and survived tens of thousands of years ago. Focusing on the Ararat-1 cave site in the Armenian Highlands, Arik explains how nearly 1,800 stone tools—including local flint and obsidian transported considerable distances—reveal a surprisingly complex technological system.

Arik first describes the work of Paleolithic archaeologists as a form of reverse engineering. "We're trying to go back, do reverse engineering, understand how they were made," he says. Rather than focusing only on the shape of finished tools, researchers try to reconstruct their entire life history, including the source of materials, how they were made, how they were used, how often they were maintained, and when they were eventually discarded. This process, Arik notes, allows archaeologists to identify "fragments of decisions." "We can actually determine when they stopped, why they stopped, and the logic behind their stopping," he explains.

Through traces left on artifacts from 35,000, 45,000 or even 50,000 years ago, the team began to reconstruct the thought processes behind them. "You can go back to how they made them and the logic behind them, which in a sense is the wonder of this work," he says.

Maintenance and Use of Ancient Tools

One of the most intriguing discoveries, he explains, is that some tools are no longer found inside the cave. Archaeologists found tiny flakes produced when tools were resharpened, but the tools themselves are not always recovered. Arik calls these "ghost tools." "We can see the resharpening segments or byproducts of them, but the tools themselves are gone," he says. Visitors to Ararat-1 appear to have carried valuable obsidian tools with them. When those tools dulled, they stopped in the cave, performed maintenance, and continued their journey. "They come here, restore them, resharpen, and continue on their way," Arik says.

These tools went through multiple rounds of maintenance, shrinking from raw pieces roughly 6 or 8 cm in length to pieces only about 2.5 cm long. Arik compares the process to repeatedly sharpening a pencil until only a tiny IKEA-style pencil remains. As a result, Ararat-1 does not appear to have been a permanent settlement or a major workshop. Evidence from hearths, animal remains, carnivores and even owl droppings suggests people stayed only briefly. The cave effectively served as a prehistoric rest and maintenance stop.

Obsidian would seem an obvious choice for cutting tools. It is volcanic glass that can produce extremely sharp edges. Variants of it are still used in some modern surgical blades. Yet experiments conducted by Arik's team produced contrary results. "Obsidian is not advantageous. If you want to use obsidian, you need to dull it rather than sharpen it," he says. Untreated obsidian edges can be too sharp and fragile for certain jobs. For example, when working animal hides, the edge might cut straight through the material instead of properly scraping or working it. "Here, you need to resharpen to make it dull," Arik explains.

Flint, by contrast, behaves differently. It is less sharp than obsidian but far more durable. Experimental tools made from flint can repeat the same motion thousands of times without suffering comparable damage. "You think the sharper thing is better than the duller, but sometimes it's the opposite," he says. Therefore, ancient toolmakers had to understand not only how to produce a sharp edge, but also how to select the right material and edge geometry for a given task. Working animals, removing skins and processing meat may each have required a different balance of sharpness, precision and durability.

Arik describes this as "a series of decisions."

Resource Management and Community Interaction

The contrast between flint and obsidian also reveals how these groups managed resources. Local flint could be collected near the cave, used for immediate tasks, and then discarded. Obsidian was different. The nearest known source lies roughly 25 miles (40 kilometers) away, and some pieces were transported as far as 124 miles (200 kilometers). This was not a flat walk. The Armenian Highlands are steep, ecological zones shift abruptly, and the volcanic sources sit above 2,000 or even 3,000 meters in elevation. Snowfall also makes some sources unreachable in parts of the year.

"In the record, moving 40 or 80 kilometers is very rare. Here, it's the norm," Arik says. Researchers cannot prove whether individuals collected the obsidian themselves or obtained it through some form of exchange. Either explanation implies extensive movement and contact between communities. "Either way, it means that people knew each other, or knew their neighbors, or they covered a very wide area in their annual movements," Arik adds.

Traveling across this region required more than physical endurance. People needed to know where resources were located, how to cross the mountains, and when those routes were safe. "You need to know where to go. If you don't have a cognitive map, you have no idea where to go and what to look for," Arik says. This cognitive map was built on knowledge accumulated across generations, encompassing geography, raw materials, water, food, climate and seasonality. "This map includes where to go, when, and so on," Arik explains. The knowledge needed to make tools also had to be transmitted between individuals.

The gestures required to knap stone are extremely precise and difficult to learn through trial and error alone. "You need to be very intimate with the person who teaches you how to do it," he says. Despite the great distances between these sites, researchers found strikingly similar toolmaking practices across the region. For Arik, this suggests that relatively small groups stayed in close contact. "There aren't many people around, but they move a lot. They know each other, and they know how to do things in very similar ways," he says.

Arik says climatic conditions in prehistoric Armenia were likely harsh. Winter temperatures dropped to around minus 20 degrees Celsius, and snowfall could reach one meter deep. Yet the archaeological record shows that these communities repeatedly survived and maintained them. "The evidence in the stones shows some kind of consistent interaction that allowed them to lower risk," he says. Their survival depended not only on tools, but also on movement, teaching and the preservation of collective knowledge. People had to know when to move to lower elevations, when to return to the mountains, and where important resources would be available. "The teaching of these people is what enabled them to survive from winter to winter," Arik explains.

As he explains, none of these conclusions come from the stone tools alone. The project brings together archaeologists, geologists, chronologists and specialists studying sediments, animals and raw materials. "All these lines of evidence, all of this detective story, come together into one overall picture." As Arik puts it, archaeologists are "trying to squeeze the essence out of the stones." From some of the smallest surviving fragments, they reconstruct how ancient people thought, traveled, engineered and survived.

How Ancient Peoples Used Resources and Knowledge to Survive

The study of ancient stone tools reveals the wisdom with which humans survived in harsh environments. By analyzing tool maintenance and use, archaeologists understand how ancient peoples selected appropriate materials to meet different needs. The contrast between obsidian and flint reflects not only technological choices but also human adaptability to the environment. In addition, interactions between communities and the transmission of knowledge demonstrate a deep understanding of resource distribution, all of which were essential to their survival strategies.