Paleofaunas and Climate in Mediterranean region: a Southeast French view

International audienceThe Mediterranean realm in Southeast France is located between three mountainous regions (Alps, Pyrenees and Massif-Central) and divided by a main north-south river and valley named The Rhône. The hydrological basin of this river is very important and presently the influence of the Mediterranean climate is sensitive higher in this Rhône’ corridor. These geomorphological features condition some partitioning, with two sub-regions (Provence at east of Rhone, and Occitanie at west), as well as a wide coastal plains and more elevated zones at the border of reliefs. In this contribution we will propose a synthetic view and multi-approaches studies (paleontology, paleoecology, biogeography, ecometry…) about the large mammalian associations considered within a diachronic perspective, namely from Late Middle Pleistocene to Late Pleistocene (from MIS 12 to MIS2). This time period is contemporaneous of major climatic phases (especially glacial vs interglacial stages), the succession of Neanderthal and Modern Human cultures, as well as a marked turnover in the faunal biomes known as an important limit between two sub-series: the Middle and the Late Pleistocene. More of 35 archeo-paleontological sites (and many more levels) record as many herbivore and carnivore associations through this space-time which can be analyzed in their dynamic sequence, quantifying several eco-biological factors (body-size, diet category..), including peculiar forms (ex. Cervid: Haploidoceros) and evolutive lineage or taxa replacement (ex. Canis, Bison, Equus…). We must note the importance of geographical factors in the taxa distribution together with the sea-level fluctuation especially marked in the west part of the region (Occitanie). Moreover, the area of Rhone delta and the corridor of this river condition strong wind flow which develop some thick deposits of eolian sands (loess), indicators of locally quite cold condition. Among evolutive traits, the particular case of caballine horses is interesting because showing special adaptive features related to the mild Mediterranean clime (peripheral zones) regardless of global climate conditions. Lastly, ecometrical analysis (meso- and micro-dental wear) developed on some sites and taxa are a valuable tool to precise local environmental features within the global climatic variations. It generally suggests a high resilience and adaptive capacities from the large and medium size herbivores (Equids, Bovids, Cervids). Paleofaunas constitute a well-documented terrestrial archives for paleoclimate reconstruction, raising issues about interactions with climate and local geographic factors; our study allow us to envision the real biological changes, responses or resilience of the mammalian guilds/biomes within this peculiar Western Mediterranean space