Morphological discriminants of Scottish wildcats (Felis silvestris), domestic cats (F. catus) and their hybrids

Skull characters of wildcats ( Felis silvestris ), classed as 'old', 'recent' or 'modern', depending on collection date, were compared with those of domestic cats ( F. catus ) and hybrids, using Fisher Linear Discriminant Functions, Principal Component Analyses and Canonical Variates. A key is derived for classification of individual (unknown) skulls. All analyses indicate that 'recent' and 'modern' wildcats were different from those collected earlier, and implied marked changes in the rate of hydridization during this century. We suggest that the older wildcat populations were a relatively 'pure' form but more recent populations contain a significant hybrid component. Although there may be a trend towards re-establishment of the earlier type, an alternative conclusion is that the 'pure' form of wildcat is effectively extinct in Scotland.