Manual annotation of circadian genes
We further manually annotated well-studied circadian genes:period (PER), timeless (TIM), Clock (CLK),cycle (CYC) and cryptochrome (CRY), using BLAST v2.2.31
(Altschul, Gish, Miller, Myers, & Lipman, 1990). Reference protein
sequences of insect circadian genes were obtained from the Uniprot
database. Conserved domains within proteins were annotated against the
conserved domain database (Lu et al., 2020). Circadian genes of the
other 15 insect species were annotated in the same way. For a common
domain of three genes (CLK, PER and CYC), a neighbor-joining tree was
constructed using MEGA7 (Kumar, Stecher, & Tamura, 2016) with 500
bootstrap replicates.