Fig. 6

Results of principal component analysis (PCA) based on the gene expression data. a Biplots of the principal component scores of examined stages during alate differentiation (PC1 vs. PC2), based on the results of the GLM analysis. The red dotted circles indicate the plots of NL and A in H. sjostedti or N2L and A in Z. nevadensis. The gray dotted circles indicate the other stages. b Principal component scores of PC2 in the respective stages in the two species. Bars indicate standard errors, and alphabetical letters indicate significant differences (n = 3–7, Tukey–Kramer test, P < 0.05). c Schematic model explaining the impacts of expression levels of 3 genes showing higher PC loadings