Recent studies of modern and ancient mtDNA in domesticated and wild cattle has indicated that members of the extinct Near Eastern aurochs population ( Bos primigenius primigenius) were the wild progenitors of European domesticated cattle ( Bos taurus) (Bollongino, R., Edwards, C.J., Burger, J., Alt, K.W., Bradley, D.G., 2006. Early history of European domestic cattle as revealed by ancient DNA. Biol. Lett. 2, 155–159; Edwards, C.J., Bollongino, R., Scheu, A., Chamberlain, A., Tresset, A., Vigne, J.-D., Baird, J.F., Larson, G., Ho, S.Y.W., Heupink, T.H., Shapiro, B., Freeman, A.R., Thomas, M.G., Arbogast, R.-M., Arndt, B., Bartosiewicz, L., Benecke, N., Budja, M., Chaix, L., Choyke, A.M., Coqueugniot, E., Döhle, H.-J., Göldner, H., Hartz, S., Helmer, D., Herzig, B., Hongo, H., Mashkour, M., Özdogan, M., Pucher, E., Roth, G., Schade-Lindig, S., Schmölcke, U., Schulting, R.J., Stephan, E., Uerpmann, H.-P., Vörös, I., Voytek, B., Bradley, D.G., Burger, J., 2007. Mitochondrial DNA analysis shows a Near Eastern origin for domestic cattle and no indication of comestication of European aurochs. Proc. Biol. Sci. 274, 1377–1385; Troy, C.S., MacHugh, D.E., Bailey, J.F., Magee, D.A., Lotfus, R.T., Cunningham, P., Chamberlain, A.T., Sykes, B.C., Bradley, D.G., 2001. Genetic evidence for near-Eastern origins of European cattle. Nature 410, 1088–1091). This observation is generally consistent with the observation of archaeo-zoologists, but there are exceptions. As cattle domestication is associated with size reduction, wild and domesticated individuals have usually been differentiated by measuring the size of the bones. But this criteria is complicated by a pronounced sexual dimorphism that makes it difficult to discriminate between male domestic cattle and female aurochs. In particular, several bone samples from the mainly terminal Mesolithic site Rosenhof LA 58 in northernmost Germany have provoked intense discussion because they are smaller than the minimum known size of Scandinavian female aurochs. Therefore, some scholars have argued that they represent the first and possibly locally domesticated bovines of the northern European Mesolithic. To clarify the status of the Rosenhof “cattle”, we determined the mtDNA-haplotype and sex of four of these presumed Mesolithic domesticates. We also analysed one early Neolithic sample and four Mesolithic robust and therefore morphologically definite wild aurochs from Rosenhof. For the purposes of comparison, we also determined the mtDNA haplotypes of seven samples from the adjacent Neolithic site of Wangels. The Neolithic samples from Wangels and Rosenhof revealed lineages that are typical of imported taurine cattle. In contrast, the four wild aurochs and the four presumed Mesolithic domesticates from Rosenhof yielded mtDNA sequences that are characteristic for European aurochs. Furthermore, all the proposed domestics from Rosenhof were female individuals while three out of four remains from Rosenhof's confirmed aurochs were males. As the four bones in question are too large to belong to female domesticates it is highly likely that they stem from wild female aurochs that were smaller than previously thought. Our data thus indicate that the beginning of cattle husbandry in Northern Germany did not predate, but is rather linked to the Neolithic transition. The single Neolithic Rosenhof domestic revealed an early radiocarbon date of 4000 ± 50 cal BC and marks the onset of the Neolithic in Northern Europe.