Climate-Human-Environment Interactions

The aim of this theme is to understand the impact that past climates may have had on societies, and conversely the more recent impact of human activity on environments.
The ANR NEHOS project, funded in 2022 and led by Thibaut Devièse, aims to precisely date the transition between Neanderthals and Homo sapiens in Europe and to assess the temporal and causal relationships between palaeoenvironmental changes and the first human populations. We are also studying the potential anthropogenic signature on the dynamics of ancient forests and savannahs in tropical Africa as part of ANR PAST-17, combining the analysis of sedimentary charcoals, phytolith and pollen assemblages, and the 17O-excess of phytoliths. The first agropastoral communities in France and the Mediterranean, and in particular the role of women, are at the heart of the ANR WomenSOFar project (2022-2026; led at CEREGE by Guillaume Leduc). The aim of this project is to understand how women eat, move around, take care of the young and participate in the activities necessary for the survival of these communities.
Our work on the archaeological time scale benefits from our developments in radiocarbon dating with the AixMICADAS spectrometer, which enables archaeological wood to be dated accurately using the wiggle-matching technique combining 14C with dendrochronology (ARKAIA Chrono-Ignis project, funded in 2022 and led at CEREGE by Edouard Bard). As part of a collaborative project between chairs at the Collège de France, we have been developing since 2016 a robust and accurate method for dating collagen micro-samples, applied to human remains from European Palaeolithic sites. For highly contaminated samples, we are developing an even more effective method for dating hydroxyproline, one of the main amino acids in collagen. We are also developing new 'green' analytical methodologies (LGO2i platform), as these enable us to considerably reduce the consumption of organic solvents, which are toxic and polluting (ecoSCience project led by Thibaut Devièse).
On more recent timescales, we are studying the presence and impact of microplastics in the Bay of Marseille and lake environments in south-east France. This approach uses expertise and methods applied in oceanography and micropalaeontology, and is led by Laurence Vidal in partnership with the Institut Carnot Eau & Environnement (PLASMA project, 2022-2025). In the same regional project, the impact of recent anthropogenic changes on biomineral plankton (mainly coccolithophores and diatoms) is being analysed using machine-learning methods developed within the team, on particle traps in collaboration with OSU Pythéas laboratories (A*Midex RapMed project, 2020-2023, coordinated by Thibault de Garidel). Longer-term trends in the response of calcareous plankton on a global scale are being analysed through a synthesis of historical trends in the biodiversity of planktonic foraminifera (FORCIS project 2020-2024, involving FRB and MPI Mainz), which will soon be extended to pteropods. We are also studying fine atmospheric particles produced naturally or by human activities, in particular flows of pyrogenic compounds into the Mediterranean (ANR FIRETRAC 2021-2025 project led at CEREGE by Edouard Bard). The origins of these particles can be determined by measuring the 14C content of micro-samples to quantify the fossil carbon content of carbon pollution of various origins.