Contribution of small vertebrates for the characterization of climatic variations from MIS 5 to MIS 3 in the northern half of France

International audienceNeanderthal populations in Europe experienced important environmental changes, especially during the Late Pleistocene, the Eemian, was followed by a climatic degradation. Previous microfaunal studies in France largely focused on meridional areas, and our knowledge of the impact of Late Pleistocene climatic changes on human and faunal populations in Northern areas is limited. Since few years, new excavations were engaged in several Middle Palaeolithic sites in the northern half of France. These sites cover a period ranging from the MIS 5 to the MIS 3, providing interesting interrogation about the occupation of septentrional areas by Neanderthals as well as faunal communities dynamics in a good chrono-stratigraphic context. These sites have yielded abundant small vertebrate remains, which have informative value on the local landscape and climatic conditions. To have a better understanding of the small vertebrate accumulations and to obtain more precise information on climatic parameters and palaeolandscapes, we chose for a multi-taxa approach (small mammals, birds and herpetofauna). We will focus on new results obtained from the Eemian layers of Waziers (Nord)and Caours (Somme), and from the upper layers of Roc-en-Pail (Maine-et-Loire). Waziers shows a great diversity of birds, specially Anatidae, in agreement with other data indicating the presence of bog and wetlands at the site during the Eemian. At Caours, several rodent, shrew and herpetofauna species also indicate a temperate period in agreement with an Eemian age. On the contrary, the upper layers of Roc-en-Pail have delivered species corresponding to an open/cold environment which could correspond to the end of the MIS 4. These new results will be compared and integrated with data from other sites located in the northern half of France, and more broadly from North-West Europe. We will especially discuss the characterization of temperate (and cold) phases in septentrional areas, in comparison with meridional areas