Figure 6 –

Principal component (PC) analyses of differentially expressed genes in mouse and bank vole M1. A PC1 and PC2 of the 500 most variable genes, showing a clear differentiation between species along PC1 and differentiation between age classes along PC2. B PC1 and PC2 of the keystone dental genes. Both PC1 and PC2 separate age classes within, but not between, the species, likely due to differences in developmental timing and molar morphology between mice and voles.