A distinct ‘biface divide’ splits Europe down the middle, with the west as a Mousterian world, where bifaces followed ancient traditions. Broadly symmetric, they have sharp perimeters flaked all – or most – of the way round. In contrast, Neanderthals in central-eastern Europe developed a very different way of doing bifaces. Known collectively as the ‘Keilmesserüppen’, they’re defined by asymmetry, with one bifacial sharp edge opposite a natural or artificially blunted margin.
