Fig. 3

Genome evolution of S. littoralis. a Phylogenetic species tree, divergence time and expansion and contraction of gene families in thirteen species. Divergence times calculated by MCMCtree, and the blue bars at the internodes indicate the 95% confidence intervals of the divergence time. Genomic comparison of thirteen sequenced species. 1:1:1 orthologs include the common orthologs with a single-copy in each species, N:N:N orthologs include the common orthologs with variable copy numbers in the different species. b The comparison of homologous genes in four species of the same genus Spodoptera. the number of species-specific genes in S. littoralis was more than that in S. frugiperda and S. exigua, and less than that in S. litura. c The number synteny blocks of S. littoralis – S. littura and S. littoralis – B. mori. The number of synteny blocks between S. littoralis and S. litura was more than that between S. littoralis and B. mori