European great tits are thought to all belong to a large population with relatively little differentiation. Interestingly, UK great tits already had a status as sub-species based on differences in their form decades ago. We were interested to know whether we could find some genetic differences between the Dutch and British great tits, and whether these differences were localized in certain parts of the genome. The fact that genes involved in face and beak shape were over-represented in these highly divergent parts of the genome led us to investigate these traits further.