Body plan evolution often occurs through the differentiation of serially homologous body parts, particularly in the evolution of arthropod body plans. Recently, homeotic transformations resulting from experimental manipulation of gene expression, along with comparative data on the expression and function of genes in the wing regulatory network, have provided a new perspective on an old question in insect evolution: how did the insect wing evolve? We investigated the metamorphic roles of a suite of 10 wing- and body-wall-related genes in a hemimetabolous insect, Oncopeltus fasciatus . Our results indicate that genes involved in wing development in O. fasciatus play similar roles in the development of adult body-wall flattened cuticular evaginations. We found extensive functional similarity between the development of wings and other bilayered evaginations of the body wall. Overall, our results support the existence of a versatile development module for building bilayered cuticular epithelial structures that pre-dates the evolutionary origin of wings. We explore the consequences of reconceptualizing the canonical wing-patterning network as a bilayered body-wall patterning network, including consequences for long-standing debates about wing homology, the origin of wings and the origin of novel bilayered body-wall structures. We conclude by presenting three testable predictions that result from this reconceptualization.
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Tergal and pleural wing‐related tissues in the German cockroach and their implication to the evolutionary origin of insect wings
The acquisition of wings has facilitated the massive evolutionary success of pterygotes (winged insects), which now make up nearly three‐quarters of described metazoans. However, our understanding of how this crucial structure has evolved remains quite elusive. Historically, two ideas have dominated in the wing origin debate, one placing the origin in the dorsal body wall (tergum) and the other in the lateral pleural plates and the branching structures associated with these plates. Through studying wing‐related tissues in the wingless segments (such as wing serial homologs) of the beetle,
- NSF-PAR ID:
- 10385237
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Evolution & Development
- Volume:
- 23
- Issue:
- 2
- ISSN:
- 1520-541X
- Page Range / eLocation ID:
- p. 100-116
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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