Insect wing shapes and the internal wing-vein arrangement are remarkably diverse. Although the wings lack intrinsic musculature to adjust shape actively, they elastically deform due to aerodynamic and inertial loads during flapping. In turn, the deformations alter the shape of the wing profile affecting the aerodynamic force. To determine how changes in wing-vein arrangement affect elastic wing deformation during free flight, we compared elastic wing deformations between free-flying rose chafers (Protaetia cuprea) and dung beetles (Scarabaeus puncticollis), complementing the comparison with wing static bending measurements. The broader relevance of the results to scarab beetle divergence was examined in a geometric morphometric (GM) analysis of wing-vein arrangement in 20 species differing in phylogeny and ecology. Despite rose chafers and dung beetles demonstrating similar flapping kinematics and wing size, the rose chafer wings undergo greater elastic deformation during flapping. GM analyses corrected for phylogenetic relatedness revealed that the two beetles represent extremes in wing morphology among the scarab subfamilies. Most of the differences occur at the distal leading edge and the proximal trailing edge of the wing, diversifying the flexibility of these regions, thereby changing the pattern of elastic wing deformation during flapping. Changes to local wing compliance seem to be associated with the diversification of scarab beetles to different food sources, perhaps as an adaptation to meet the demands of diverse flight styles.
|Journal||Royal Society Open Science|
|State||Published - 1 Apr 2020|
Bibliographical noteFunding Information:
Ethics. Insect collection was carried out under permit (no. 41750) from the Israel Nature Protection Agency. This article does not present research with ethical considerations. Data accessibility. Data are available through the electronic supplementary material or through links referring to the data. Authors’ contributions. Y.M. and G.R. conceived the ideas, designed the study and collected specimens; Y.M. performed the experiments; Y.M. and J.F.H. performed the GM analysis; Y.M. and R.B.-S. performed the phylogenetic analysis. All the authors contributed to the drafts and gave final approval for publication. Competing interests. We declare we have no competing interests. Funding. This research was supported by the Israel Science Foundation grant (no. 849/15) to G.R., and the Naomi Prawer Kadar Foundation GRTF Program to Y.M. Acknowledgements. We thank O. Rittner for help in identifying beetles and N. Paz for English editing.
© 2020 The Authors.
- Elastic deformation
- Flapping flight
- Free flight
- Functional morphology
ASJC Scopus subject areas