Fig. 3

Principal Component Analysis of copepodid samples clustered by gene expression. Samples are quality filtered transcriptome profiles of lice pools that are either positive (blue) or negative (red) for the microsporidia infection. Clustering indicates that PC1 (X-axis) explains the most variation, with 29.5% of total variation explained. Samples were either exposed to the parasiticide emamectin benzoate (triangles) or control (square), but this had less of an effect than that of the microsporidia. PC2 (Y-axis) explains 24.5% and PC3 (Z-axis) explains 7.1% of the total variation. PC2 and PC3 were not as clearly associated with a treatment group as was the infection status, which was separated along PC1