The Impact of Magdalenian Hunter-Gatherers on Their Environment

Abstract

Anthropological and ethnographic research has shown the influence of climate and resource distribution on hunter-gatherer lifestyle. As a result, an increasing number of archaeologists have attempted to reconstruct past environments to understand behavior in its context. However, to this day, only a few have considered the possibility that hunter-gatherers themselves impacted the environment and resources on which they relied. This research aims to reconstruct Southwest European Magdalenian environment and evaluate the potential impact that Magdalenian hunter-gatherers had on that environment. It uses multiple Random Forest models trained on modern environmental data and applied to prehistoric environmental data to reconstruct the distribution of 3720 plant taxa aggregated into 22 plant functional types (PFT), which are then grouped into biomes. The modern distributions of the PFT are assessed through crowd-sourced data, and a model of their climate requirements is built using Random Forest. Those requirements are then applied to Magdalenian climate to reconstruct the PFT’s probable prehistoric distributions. Magdalenian climate maps use data from the CHELSA downscaled Trace-21 ka global climate model. In the scenario without human impact, the PFT distributions are combined to form biomes. In the scenario with human impacts, a Random Forest model is built using archaeological sites to predict the distribution of Magdalenian hunter-gatherers, which affects the threshold of PFT’s presence prior to being combined into biomes. The reconstructed biomes of both scenarios are then compared to the archaeological pollen record to evaluate which scenario (with or without human impact) fits the empirical data best.