Principal component analysis of the GO category composition of all genes in each genome/transcriptome and WGD paralogs. Principal component analysis of the GO category composition of all genes in each genome/transcriptome and WGD paralogs. Red circles indicate number of genes annotated to each GO category in the whole genome or transcriptomes; black circles, number of WGD paralogs annotated to each GO category. Ellipses represent the 95% confidence interval of SD of point scores. Zheng Li et al. PNAS 2018;115:18:4713-4718 ©2018 by National Academy of Sciences