FIGURE LEGENDS
Figure 1. Geographic distribution of the included isolates ofSerpula lacrymans from the built environment in Europe, Japan and New Zealand. a-c show genetic assignment groups using the software Admixture. Large pie charts indicate results from the full data set (Admixture K = 2), the smaller pie charts indicate genetic structuring when each population was analyzed separately. As only two isolates were included from New Zealand, they were not analyzed separately and the small pie charts are derived from the full data set. d) demonstrate the assignment for all 36 isolates (each bar shows the assignment for one individual) to K = 2, K = 4, K = 5, and K = 7 (i.e. those with the lowest cross validation error; see Supplementary Figure S1).
Figure 2 . Principal Component Analyses of 419,196 SNPs from 36 isolates of the dry rot fungus Serpula lacrymans . a) analyses of the full dataset, colored by geographic origin b) analyses of a separate data set of only European strains, colored by the two groups from Europe when the full data set was separated by K = 4 (Fig 1d), c) analyses of a separate data set of only Japanese strains, colored by geographic origin from S (Honsu) or N (Hokkaido).
Figure 3. Manhattan plot of DXY and FST between the European and Japanese populations ofSerpula lacrymans using 10 kb genomic windows along the 30 largest scaffolds of the European S. lacrymans S7.3 genome. Black and grey dots separate the adjacent scaffolds. a) DXY, b) FST.
Figure 4. The three different models used in Fastsimcoal2 when modelling the demographic history of the Japanese and European populations. Two different mutation rates were used, 10-7 and 10-8. The model with a population split followed by a bottleneck is the most probable with a lower AIC. The current effective population size is annotated with N, while Bot indicates the effective population size of the bottleneck. TBot indicates time since bottleneck, TDIV indicates time since populations diverged.
Figure 5 . The genomic assignment of the two isolates ofSerpula lacrymans from New Zealand (sl 950 and ICMP18202) to the European and Japanese populations estimated with PCAdmix. Strain ID-a and -b indicate the two different haplotypes after phasing the SNPs from the dikaryotic strains using Beagle. Blue indicates parts of the genome assigned to the European population, while yellow indicates parts of the genome assigned to the Japanese population. The x-axis represents the scaffolds.
Figure 6 : Linkage decay of the European and the Japanese population of Serpula lacrymans . Blue indicates the European linkage decay while yellow indicate Japanese linkage decay. Distance in x axis indicate number of base pairs, while R2 indicates linkage disequilibrium.
Figure 7 . Manhattan plots of nucleotide diversity, π, and Tajima’s D along the genome of Serpula lacrymans for 10 kb genomic windows. a) π of European isolates, b) π of isolates from Japan, c) Tajima’s D of European isolates and d) Tajima’s D of isolates from Japan.
Figure 8 . The wood decay rates of Serpula lacrymans on spruce, fir and pine for isolates from Europe, Japan and New Zealand. Five, four and one isolate included in the mass loss experiments from Japan (yellow), Europe (blue) and New Zealand (green), respectively. The y axis indicates the percent mass loss of the wood blocks after 60 days of decay.