Fig 4.

Sampling sites of A. alpina in the Italian-Alpine expansion zone (with mating types as published in [57, 59] and map drawn using the world dataset in the R package maps [65]) (A). Inbreeding coefficients for individuals across sampled populations, including Spain (selfing), Scandinavia (selfing), and Greece (outcrossing, [58]) (B). The distribution of nucleotide diversity estimated for Italian and alpine populations (C), with diamonds indicating group means. $R_{xy}^{\prime }$ values for predicted deleterious (nonsense and missense variants; purple) and LoF (orange) loci are shown for each pairwise population comparison and sorted by increasing order within each region (D). Confidence intervals are smaller than point sizes and thus not shown. $R_{xy}^{\prime }>1$ indicates an accumulation of derived alleles at deleterious or LoF sites relative to neutral sites, while $R_{xy}^{\prime }<1$ indicates a deficit.