Different population structures in northern and southern populations of the European blue tit (Parus caeruleus)

Abstract

Abstract We sequenced the control region of the mitochondrial DNA from a sample of six European blue tit populations to investigate the phylogeography of Parus species. Along a transect from Barcelona, Spain to Oulu, Finland, the blue tit showed a different phylogeographic structure than the great tit and the willow tit. The southernmost sample from Barcelona consisted of two widely divergent maternal lineages (nucleotide divergence, π = 0.30%), a situation also found earlier in the French Alps. The more northern populations had a relatively uniform structure (π = 0.19%) with distinctive marks of a growing population, thus resembling the great tit populations (π = 0.19%). The amount of genetic variation among blue tits is lower than in the willow tit (π = 0.53%). This probably reflects a smaller long-term effective population size in the great tit and the blue tit than in the willow tit. The different genetic structure of the Barcelona population vs. the rest had an influence on the estimated population parameters, which are calculated based on the assumptions of genetic equilibrium of the populations.