Abstract
The bright green dorsal iridescence of the hindwings of Neurobasis chinensis chinensis males, very rare in Odonata, is known to play a significant role in their courtship behaviour. The mechanism responsible for such high contrast and spectrally pure colour has been investigated and found to be optical interference, producing structural colour from distinct laminations in the wing membrane cuticle. The ventral sides of these iridescent wings are dark brown in colour. In a single continuous membrane of wing cuticle, this is an effect that requires a specialized structure. It is accomplished through the presence of high optical absorption (kappa = 0.13) within two thick layers near the ventral surface of the wing, which leads to superior dorsal colour characteristics. By simultaneously fitting five sets of optical reflectivity and transmissivity spectra to theory, we were able to extract very accurate values of the complex refractive index for all three layer types present in the wing. The real parts of these are n = 1.47, 1.68 and 1.74. Although there is often similarly significant dorsal and ventral colour contrast in other structurally coloured natural systems, very few system designs comprise only a single continuous membrane.
Full Text
The Full Text of this article is available as a PDF (457.8 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Ghiradella H., Aneshansley D., Eisner T., Silberglied R. E., Hinton H. E. Ultraviolet reflection of a male butterfly: interference color caused by thin-layer elaboration of wing scales. Science. 1972 Dec 15;178(4066):1214–1217. doi: 10.1126/science.178.4066.1214. [DOI] [PubMed] [Google Scholar]
- Land M. F. The physics and biology of animal reflectors. Prog Biophys Mol Biol. 1972;24:75–106. doi: 10.1016/0079-6107(72)90004-1. [DOI] [PubMed] [Google Scholar]
- Lawrence Chris, Vukusic Peter, Sambles Roy. Grazing-incidence iridescence from a butterfly wing. Appl Opt. 2002 Jan 20;41(3):437–441. doi: 10.1364/ao.41.000437. [DOI] [PubMed] [Google Scholar]
- Mckenzie D, Large M. Multilayer reflectors in animals using green and gold beetles as contrasting examples . J Exp Biol. 1998 May;201(Pt 9):1307–1313. doi: 10.1242/jeb.201.9.1307. [DOI] [PubMed] [Google Scholar]
- Neville A. C., Caveney S. Scarabaeid beetle exocuticle as an optical analogue of cholesteric liquid crystals. Biol Rev Camb Philos Soc. 1969 Nov;44(4):531–562. doi: 10.1111/j.1469-185x.1969.tb00611.x. [DOI] [PubMed] [Google Scholar]
- doi: 10.1098/rspb.1999.0794. [DOI] [PMC free article] [Google Scholar]
- Smith C. W., Herbert R., Wootton R. J., Evans K. E. The hind wing of the desert locust (Schistocerca gregaria Forskål). II. Mechanical properties and functioning of the membrane. J Exp Biol. 2000 Oct;203(Pt 19):2933–2943. doi: 10.1242/jeb.203.19.2933. [DOI] [PubMed] [Google Scholar]
- Spurr A. R. A low-viscosity epoxy resin embedding medium for electron microscopy. J Ultrastruct Res. 1969 Jan;26(1):31–43. doi: 10.1016/s0022-5320(69)90033-1. [DOI] [PubMed] [Google Scholar]
- Vincent J. F. Insect cuticle: a paradigm for natural composites. Symp Soc Exp Biol. 1980;34:183–210. [PubMed] [Google Scholar]
- Vukusic P., Sambles J. R., Lawrence C. R. Colour mixing in wing scales of a butterfly. Nature. 2000 Mar 30;404(6777):457–457. doi: 10.1038/35006561. [DOI] [PubMed] [Google Scholar]
- Vukusic P., Sambles J. R., Lawrence C. R., Wootton R. J. Limited-view iridescence in the butterfly Ancyluris meliboeus. Proc Biol Sci. 2002 Jan 7;269(1486):7–14. doi: 10.1098/rspb.2001.1836. [DOI] [PMC free article] [PubMed] [Google Scholar]