Fig. 3: k-mer content clusters Nunavik gut microbiomes.

The heatmap represents the Euclidean distance between k-mer genomic content of Nunavik and comparison samples, as computed by Ray Surveyor. Dendrograms on the X and Y axes of the heatmap represent metagenomic samples ordered based on hierarchical clustering of k-mer content distance matrix. At the leaves of the dendrograms are colored markers of each sample’s population (see legend). Within the heatmap, the darker the shade of red, the higher the similarity between metagenomes. At the top left of the heatmap, the dark red square represents the industrialized cluster and indicates that samples from the gray and khaki dendrogram branches are similar in genomic content. The two branches are composed of 69.4% and 70% of industrialized samples, respectively. Similarly, the dark red color in the center of the heatmap defines the Nunavik cluster, where the blue branch consists of 99.4%, and the pink of 76.2 % samples from Nunavik. Lastly, the bottom right square constitutes the non-industrialized cluster, with the light blue and yellow branches composed of 57.7% and 93.3% of non-industrialized samples respectively.