Craniometric differentiation of the European brown hare (Lepus europaeus Pallas 1778) across different habitats in Serbia

The European brown hare (Lepus europaeus Pallas, 1778) is very important game species distributed across Europe. We tested the hypothesis that the populations of the European brown hare from five localities in Serbia differ significantly in size and shape of the cranium. Craniometric analysis based on 21 craniometric measurements was performed on the 71 skulls and mandibles from five localities: Čelarevo (18 individuals, intermediate habitats), Novi Sad (6 individuals, оpen habitats), Ada (6 individuals, оpen habitats), Stragari (21 individuals, closed habitats) and Knić (20 individuals, closed habitats). Analysis of variance, principal component analysis and canonical discriminant analysis were used to analyze craniometic measurements. We expected different levels of cranial variability in closed habitats which are characterized by stable and predictable (more homogenous) environments, intermediate habitats, and in open habitats which are characterized by unstable, fluctuating (more heterogeneous) environments. The results showed partial grouping of populations in accordance with the habitat type (open, closed and intermediate). Both populations from closed habitats (Stragari and Knić) had smaller skulls. However, when observing intermediate and open habitats, lesser differences existed, especially between individuals from Čelarevo (intermediate habitat) and Novi Sad (open habitat). The observed differences are probably the result of adaptations to diverse environmental conditions at different habitat types. These preliminary results suggest that differentiation of populations in accordance with habitat type does exist in European brown hare, and further analyses on greater sample size and number of populations are needed to understand the influence of habitat conditions on cranial variability of this species.