The growth of the human population since the end of the last Ice Age has been anything but steady. Historical records and archaeological findings reveal a pattern of rapid expansions followed by sharp declines. While environmental factors, such as climate change and natural disasters, have traditionally been blamed for these fluctuations, recent research suggests that social conflicts might have played an equally, if not more, significant role.
The Role of Social Conflicts in Population Fluctuations
In a study published in the Journal of the Royal Society Interface, scientists from the Complexity Science Hub (CSH), led by Peter Turchin and Daniel Kondor, along with an international team of collaborators, have explored how social conflicts could have influenced population dynamics in Europe, particularly during the Neolithic period (circa 7000 BC to 3000 BC). Their findings provide new insights into how fear, driven by wars and conflicts, shaped the settlement patterns and demographic trends of prehistoric societies.
Fear and Population Dynamics
Wars and conflicts not only result in direct casualties but also create an environment of fear and uncertainty. This fear can significantly impact human behavior, particularly in terms of settlement decisions. When people fear for their safety, they are likely to abandon their homes or avoid certain regions altogether. This behavior can lead to population declines in conflict-prone areas and force people to congregate in safer, more defensible locations.
Daniel Kondor from CSH explains, “Globally, scientists have extensively studied and debated the presence and role of conflicts in prehistory. However, estimating their effects, such as those on population numbers, is still difficult.” The study suggests that these indirect effects of conflict, such as flight and avoidance of certain areas, could have caused significant long-term population fluctuations in non-state societies.
The Impact of Overpopulation in Safe Zones
As populations fled to safer areas, these regions often became overcrowded. Overpopulation, in turn, could have led to higher mortality rates and lower fertility due to the strain on resources and the increased likelihood of disease spread. Kondor points out, “Our model shows that fear of conflict led to population declines in potentially dangerous areas. As a result, people concentrated in safer locations, such as hilltops, where overpopulation could lead to higher mortality and lower fertility.”
This phenomenon matches archaeological evidence from sites like Kapellenberg near Frankfurt, which dates back to around 3700 BCE. Here, there is evidence of temporal abandonment of open agricultural land, with groups retreating to more defensible locations. These sites often feature large-scale defense systems, such as ramparts, palisades, and ditches, indicating a strong focus on protection and security.
The Rise of Political Structures and Wealth Disparities
The concentration of people in specific, well-defended locations could have also contributed to the emergence of wealth disparities and early political structures. As Peter Turchin from CSH notes, “This concentration of people in specific, often well-defended locations could have led to increasing wealth disparities and political structures that justified these differences.” In this way, the indirect effects of conflict might have played a crucial role in the development of larger political units and the rise of early states.
Integrating Complexity Science and Archaeology
To better understand these population dynamics, the researchers developed a computational model that simulates population trends in Neolithic Europe. This model was tested using a database of archaeological sites, analyzing the number of radiocarbon age measurements from various locations and time periods. These measurements were assumed to reflect the scale of human activities and, ultimately, population numbers.
“This allows us to examine the typical amplitudes and timescales of population growth and decline across Europe,” Kondor explains. The goal was to ensure that the simulation accurately reflected the observed patterns in the archaeological record.
The study represents a significant step forward in understanding the complex interactions between social conflicts and population dynamics. By integrating complexity science methods with archaeological data, the researchers were able to develop a more nuanced understanding of how prehistoric societies responded to conflicts.
Future Directions
Looking ahead, the model developed by the CSH team could help interpret archaeological evidence, such as signs of overpopulation or land use patterns. This, in turn, can provide necessary context and data for further refinements to the modeling process. The study exemplifies the potential of interdisciplinary collaboration between complexity scientists and archaeologists.
“Using complexity science methods, we develop mathematical models to analyze the rise and fall of complex societies and identify common factors,” Turchin explains. “For the most complete picture possible, direct collaboration with archaeologists is immensely important. This study is a great example of the potential that such interdisciplinary collaboration can have,” Kondor emphasizes.
Source: Complexity Science Hub Vienna