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To test our hypothesis, we have modeled and analyzed the distribution of Neanderthals during the full Eemian Interglacial (MIS 5e, $\sim$130 ka BP) using a palaeo species distribution modeling approach (PSDMs hereafter) \cite{Franklin20151, Svenning20112930, Varela2011451}. PSDMs rely on the same principles of species distribution modeling \cite{Guisan2000147, Guisan_2005}, requiring presence coordinates coming from fossil/archaeological remains, a set of predictors (usually palaeo-climatic simulations), and an algorithm to define the relationship between presence and predictors. The result of a PSDM can be defined as a \emph{habitat suitability map}, a raster map in which each cell is scored according to how well it resembles the ecological conditions of the localities the species occurs \cite{Soberon_2005}. PSDMs rely on the assumption that the modeled species is in equilibrium with its environment, and therefore occurs in all the localities with suitable habitat \cite{Guisan_2005}. Aside from providing a graphical description of the potential distribution of the species, PSDMs can be used to analyze the influence of particular drivers over the species distribution and gain ecological knowledge, as in \citet{Varela_2009} or \citet{Rodr_guez_S_nchez_2008}. PSDMs have been used before to study the distribution of Neanderthals and Anatomically Modern Humans (I am not sure this has to be capital) \cite{Burke201435, Banks_2008, Banks2008481, Beeton_2013}, but in this paper we add to the previous studies by applying a new approach based on recursive partitioning trees to assess the importance of predictors at the local scale, and offer a novel insight into the drivers of Neanderthals distribution.  We selected the Eemian Interglacial (MIS 5e, $\sim$130 ka BP) as our modeling period for three different reasons: 1) the distribution of Neanderthals during this period has been previously assessed by i.e. \citet{Richter2005}, \citet{Richter2006}, \citet{Wenzel_2007}, and \citet{Gaudzinski2011} \citet{Gaudzinski2011},  providing a good baseline knowledge of the site distribution, but with these studies mainly focusing on the core and northern edge of the distribution area across central Europe, and  lacking a quantitative description of Neanderthals distribution and its limiting factors; 2) the publication of \citet{Wenzel_2007}, Neanderthal remains attributed to the Eemian have been found in Spain \cite{ÁlvarezAlonso2014288, Arsuaga2012629}, Italy (CITATION!), France \cite{Moncel200765}, these new sites have the potential to change our view about the Eemian distribution of Neanderthals; 3) During the Eemian, the warmer climatic conditions freed Europe from the Saalian ice sheet, offering the Neanderthals a unique opportunity to spread throughout Europe for c. 10000 years, and probably allowing them to reach their maximum range size. The Eemian can therefore be considered the most suitable period to assume a pseudo-equilibrium with climate for Neanderthals distribution, a key assumption for PSDMs \cite{Guisan_2005, Guisan2000147}. In summary, in this paper we propose a hypothesis about how abiotic drivers (climate and topography) could have shaped Neanderthals distribution throughout Europe, and we test it by fitting and analyzing a PSDM describing their distribution during the Last Interglacial period. 
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