Dr. Yoshi Tomoyasu (Department of Biology, Miami University, Oxford, Ohio, USA)

2017年05月15日(月) 16:00 より 17:00 まで

明大寺地区１階　会議室 (111)

形態形成研究部門　上野 直人 (7570)

The evolutionary origin of insect wings has been the subject of heated debates for centuries. These debates have culminated into two prominent, yet contrasting hypotheses: the tergal origin hypothesis and the pleural origin hypothesis. However, despite accumulating efforts to unveil the origin of insect wings (including developmental, taxonomical, and paleontological analyses), neither hypothesis has been able to surpass the other. Through investigations in the Tribolium beetle, we have previously obtained functional evidence supporting a third hypothesis, the dual origin hypothesis. Although this hypothesis has the potential to unify the two competing wing origin hypotheses, it requires rigorous testing from various fields. To further evaluate this hypothesis from an evo-devo perspective, we have been analyzing the development of wings and wing (serial) homologs in a wide taxonomy of organisms, including a fly (Drosophila), a beetle (Tribolium), a cockroach (Blattella), and a crustacean (Parhyale). Through these analyses, we have made several interesting findings that can help decipher the origin of insect wings. For example, in Parhyale, we identified two tissues that are potentially homologous to insect wings. In Tribolium, we found that the formation of ectopic wings induced by homeotic transformations in otherwise wingless segments requires the merger of two separate groups of wing serial homologs. In this talk, I will showcase these findings and discuss how our results support the idea that the insect wing is composed of two separate lineages of tissues (of tergal and pleural nature), and therefore further support a dual origin of insect wings.

Tomoyasu, Y., Ohde, T., Clark-Hachtel C.M. What serial homologs can tell us about the origin of insect wings. F1000Research 6: 268 (2017)

Clark-Hachtel C.M.**, Tomoyasu, Y. Exploring the origin of insect wings from an evo-devo perspective. Current Opinion in Insect Science 13: 77-85 (2016)

Clark-Hachtel C.M., Linz D.M., Tomoyasu Y. Insights into Insect Wing Origin Provided by Functional Analysis of vestigial in the Beetle, Tribolium castaneum. Proc Natl Acad Sci USA 110(42): 16951-6 (2013)

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