Fig. 2.

Bayesian phylogenetic analysis of unique gdh and bg sequence fragments. Sequences of representative samples are shown and number of samples with identical sequences is given in brackets. Unrooted phylogenetic trees comprised of 29 unique gdh and 59 unique bg sequences that have been classified as G. microti (purple clade) and 4 unique bg (and none gdh) sequences classified as G. muris (blue clade). Further reference sequences (GenBank accession numbers) for bg were included: G. muris (EF355599) and G. duodenalis (X85958, assemblage AI; Y072725, assemblage B; green clade). References for gdh included G. duodenalis (M84604, assemblage AI; AY178738, assemblage B; green clade) and G. ardae gdh (AF069060; red clade) sequences. Reference sequences are marked in bold. Only posterior probabilities ≥ 0.5 are highlighted. Rodent species and number of samples from which unique sequences derived are illustrated in color bars (one square size represents one animal). Maximum likelihood analysis based on PhyML resulted in similar trees (not shown). Testing for significant phylogeny-trait correlations within the G. microti subgroup for host distribution clustering using the programme BaTS [51] revealed the following P-values: gdh, Myodes = 0.079, Microtus ≤ 0.001; bg, Myodes ≤ 0.001, Microtus ≤ 0.001