How Savvy Neanderthals Used Rivers To Travel Long Distances Across The World

NEW YORK — New research reveals that our extinct Neanderthal relatives were surprisingly savvy navigators who used river valleys to zip across continents in record time. Computer simulations show they could cross from western Russia to Siberia in as little as 1,600 years, a prehistoric speed record that shows the efficiency of their migration skills.

A new study published in PLOS One reveals that Neanderthals could have traveled from the Caucasus Mountains to the Altai Mountains of Siberia in the blink of an eye in prehistoric terms. Using sophisticated computer simulations that model ancient migration patterns, researchers from New York University discovered that these early humans consistently chose northern routes through what is now Russia, following river valleys across the continent.

This means that Neanderthals were far more mobile and adaptable than previously thought. The research indicates that geography itself may have made eastward expansion almost inevitable, meaning the landscape practically guaranteed Neanderthal migration to Siberia.

Following Ancient Highways

The research team used an approach called “agent-based least-cost path modeling” to simulate how Neanderthals might have navigated the challenging terrain between western and eastern Eurasia. These virtual Neanderthals avoided steep mountains, impassable rivers, and areas with harsh climates.

The computer simulations placed digital “agents” representing Neanderthal groups in the Caucasus Mountains, roughly where modern-day Georgia and Russia meet, and then watched as they made movement decisions based only on what they could see in their immediate surroundings. The agents had no predetermined destination; they simply moved toward areas that required the least energy to traverse.

Time after time, the simulated Neanderthals gravitated toward the same northern route, following river valleys like the Volga and Kama Rivers eastward, then crossing the Ural Mountains and continuing along the Ob and Irtysh Rivers toward the Altai region of southern Siberia.

Speed Demons of the Stone Age

Out of 110 computer simulations, only three successfully reached the Altai region, but those that did completed the journey in roughly 925,000 to 1.1 million individual steps. When researchers converted this to real-world time using data about how far hunter-gatherer societies typically travel in a year, they found that Neanderthals could have covered the distance in approximately 1,500 to 1,900 years.

This timeframe is fast for prehistoric migration. The speed of Neanderthal expansion suggests they were highly mobile and efficient travelers, capable of covering vast distances without getting bogged down in any particular region.

The successful simulations occurred during two specific time periods: Marine Isotope Stage 5e (roughly 130,000-115,000 years ago) and Marine Isotope Stage 3 (approximately 60,000-25,000 years ago). Both periods were characterized by relatively mild climates that made long-distance travel more feasible.

River valleys provided fresh water, supported game animals, and offered relatively flat terrain for easier walking. The Volga-Kama corridor was a particularly important route, funneling travelers from the Caucasus toward the Ural Mountains. Once across the Urals, migrants followed the Ob and Irtysh Rivers southeast toward the Altai region.

This pattern appeared so consistently in the simulations that the researchers concluded geography itself was channeling Neanderthal movement. Even the formidable Ural Mountains proved passable when travelers followed river valleys that cut through the range.

Computers vs. Archaeology

The computer simulations align well with real archaeological evidence. Neanderthal fossils and tools have been found at sites like Chagyrskaya and Okladnikov Caves in the Altai region, dated to around 59,000 years ago, which falls squarely within the Marine Isotope Stage 3 timeframe identified by the simulations.

Genetic evidence also supports this rapid Neanderthal expansion. DNA analysis suggests a major dispersal of Neanderthals from Europe to Asia occurred between 120,000 and 80,000 years ago, again matching the timeline suggested by the computer models.

The simulations found no evidence for southern migration routes through areas like Iran or Afghanistan, despite the presence of some Neanderthal sites in Central Asia. All successful routes in the study went north through the Urals and southern Siberia, suggesting that if Neanderthals did reach southern regions, they likely took a different starting point or used different strategies than those modeled in this study.

Successful migrations occurred only during specific climate windows when conditions were favorable for long-distance travel. During colder periods, such as Marine Isotope Stage 4 (approximately 70,000-60,000 years ago), the simulations showed Neanderthals getting partway across Eurasia but failing to reach the Altai region.

This suggests that climate change may have determined when and where Neanderthals could expand their range. Warmer periods opened up northern routes that were impassable during ice ages, creating brief opportunities for rapid expansion across the continent.

The timing of these climate windows may have been critical for Neanderthal survival and interaction with other human species. The research notes that successful northward migrations would have brought Neanderthals into contact with Denisovans, another archaic human species known to have inhabited the Altai region. Genetic evidence confirms that these groups did indeed interbreed, producing hybrid offspring.

The computer models don’t account for factors like seasonal weather patterns, availability of food and water sources, vegetation preferences, or social dynamics within Neanderthal groups. The researchers note that future versions of the model will incorporate additional variables to create more realistic scenarios.

The study also relied on static representations of ancient landscapes, making it impossible to include sudden environmental changes like volcanic eruptions or earthquakes that might have influenced migration patterns.

River valleys, mountain passes, and climate patterns may have made certain migrations virtually inevitable for our early ancestors. Rather than being slow, lumbering cave dwellers, archaic humans may have been efficient long-distance travelers capable of rapid expansion across diverse environments.