Modelling the demography of agricultural tran

Understanding the shift from hunting and gathering to farming has been a major concern in the study of human history. Often this major transition is attributed to external factors such as environmental changes. The shift could have happened in two ways: either groups developed agriculture independently, or these early farming groups interacted with hunter-gatherers who then adopted these new techniques.

“In our new study, we argue that humans were not just passive participants in this process; they played an active and crucial role in this transition,“ says first author Alfredo Cortell-Nicolau from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the University of Cambridge in the UK. “We focus on how the population dynamics of these groups directly influenced the adoption of agriculture.“ To study this, the research team adapted an ecological model that imitates the interactions between different species, in particular between predators and prey. In this context, farmers are the ‘predators’ and the hunter-gatherers are the ‘prey’. Factors such as group migration and cultural assimilation were also included in the analysis.

Radiocarbon dates as a demographic proxy

The researchers used radiocarbon dating as a basis for this model. These dates, mostly from organic material, act as a demographic proxy – the more dates, the larger the population. “By statistical fitting our model to observed population dynamics inferred from the radiocarbon dates, we can better understand how our variables relate to the existing archaeological record,” explains co-author Enrico Crema from the University of Cambridge. “Using this model, we were able to explore what conditions could have promoted a rapid diffusion of farming economy or a longer persistence of hunter-gather lifestyle.“

The researchers also applied this model to specific case studies – eastern Iberia (Spain), Kyushu Island (Japan) and Scandinavia (Denmark). Looking at these areas showed how different factors, such as different population growth rates or mortality rates caused by competition between hunter-gatherers and farmers, played a role in the agricultural development of these regions.

Expanding the archaeological toolbox

“Our study provides valuable insights into several aspects of prehistoric society. By applying this method, we were able to determine the impact of population growth on historical developments and observe some interesting phenomena, such as how the mode of agricultural expansion – terrestrial or maritime – affects the demographic dynamics of the interacting groups,” explains co-author Javier Rivas from the University of Bath in the UK. “More broadly, the model suggests the role of migration rates and social assimilation in the adoption of farming”.

In the future, the researchers plan to include more complex factors and apply their model to larger regions. “We hope that the methods we developed will one day serve as a standard tool for studying past demographic interactions, providing insight into many prehistoric transitional periods beyond the transition to farming,” the authors conclude.