3.3 Phylogenetic analysis
To infer the evolutionary status and trace the phylogenetic placement ofC. japonica , we did phylogenetic analysis for 10 insects
(D. melanogaster , P. xylostella , D. plexippus ,A. yamamai , B. mori , A. pernyi , C. japonica ,S. ricini , S. frugiperda , H. armigera ). 177071
genes were assigned by OrthoFinder, and 158040 genes were in orthogroups
(89.3%) of 10 insects compared in our analyses. The total number of
orthogroups is 17425, and there are 4382 orthogroups (25%) shared by
all ten tested insects. Next, we used 1167 single-copy genes identified
by OrthoFinder to the construct a phylogenetic tree, showing thatC. japonica is diverged from Antheraea about 42.7 million years
ago. There are 1812 genes expanding and 1665 genes contracting.