Abstract: Since 1978, characterization of the homeotic bithorax mutations of Drosophila has led E.B. Lewis to presage the growth of work on comparative developmental genetics, which focuses mainly on Hox genes, and afterward greatly adds to our understanding of the genetic basis of morphological evolution. Here, we reviewed the latest progress in the origin of insect wing and work on developmental genetics underlying wing modification. According to fossil records, primary insects bear appendages (including wings) on all thoracic and abdominal segments, while modern insects evolve to bear only two pairs of wings on T2 and T3, due to Hox suppression to wing development in other segments. Of the ten arthropod Hox genes known, Ubx has hindwing identity, and regulates its targets to make the fore-and hind-wing different in morphology. We especially compared Hox expression pattern of insects with most modified wings in three orders: Coleoptera (forewing to elytra), Diptera (hindwing to haltere) and Strepsiptera (forewing to haltere). Recent studies show that function of Ubx in beetle hindwings represents a previously unknown mode of wing diversification in insects. However, more study on Strepsiptera is necessary.

Key words: Insect wing, origin, modification, Hox, Ubx, morphological evolution