English: The Tomoyasu lab hypothesized that wings evolved from two distinct body wall regions (the tergum and pleural plate) fusing together and growing out of the body. They found that a tergal tissue in the abodmen of Tribolium, the pupal defense gin-traps, expresses "wing" genes. When they knocked down Hox genes responsible for abdominal fates, the tergal tissue that normally become a gin trap fused with pleural tissue to form a wing-like outgrowth. This finding supports their hypothesis that the ancestor to insects had serially homologous pleural tissues that evolved into gill branches in crustaceans. Serially homolous tergal tissues evolved into gin-traps in the abdomen of Tribolium. In the thorax of insects, these tergal and pleural tissues fuse to form wings.

Reference:

"Dual evolutionary origin of insect wings supported by an investigation of the abdominal wing serial homologs in Tribolium" (2017), PNAS, David M. Linz and Yoshinori Tomoyasu, https://doi.org/10.1073/pnas.1711128115