Faunal input for evolutive dynamics of Neandertal populations in France

The disappearance of Neandertal in Western Europe is a main issue that has been debated for decades in many studies with no clear resolution until now. Three years ago we started the project NeDeMo (Neandertal Demise Modelisation) in a pluridisciplinary research group with the explicit goal of identifying crucial demographic parameters that resulted in Neandertal demise. We used classical ecological models to test different values of vital statistics and we verified [1, 2, 3] that very small changes in fertility and/or survival rates were sufficient to account for the disappearance of the Neandertal population. In order to improve our models the group NeMoMo (Neandertal Mobility Modelisation) was created to take into account the different bioclimatic context and mam- malian associations during the Upper Pleistocene. Thus a preliminary palaeoecological analysis was undertaken starting from the NeMoMo faunal database of available archaeological and natural French sites. This database includes more than 100 stratigraphic sequences/levels containing approximatively 90 large and 50 small mammals from OIS 5 to OIS 2. Our study is founded on their ba- sic trophic preferences regarding habitat (waterside; mountain; meadow-parkland-forest; meadow-steppe-tundra), diet (browsers; grazers; mixed-feeders; frugivorous-granivorous-insectivorous which concern most of the small mammals; carnivores; omnivores) and body-weight (from 850 kg); all variables being inferred on the basis of modern species. From a methodological point of view, we combined evolution of weight-classes, prey/predator ratio, index of Sorensen, species richness and relative diversity to test the similarity between faunal associations through time and space. Factorial analysis is used to detect underlying structures from these associations in order to identify the dynamics and the main ecological trends for each temporal unit during Upper Pleis- tocene (OIS 5 to 2). In this poster we address two key questions: is there clear pattern of mammalian distribution through time? Are changes in taxonomical composition related to taphonomic biases, environmental conditions and/or human or carnivore impact?