ArticleJournal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology2018
Iridescent colouration of male Anna's hummingbird (Calypte anna) caused by multilayered barbules.
Article in Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.
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Who cites it
6 citing papers in PubMed.
- How barbule orientation drives iridescent coloration in Coeligena hummingbirds.Scientific reports · 2026Article
- Bioinspired Real-Time Dynamic Responsive Structural Colors.Polymer science & technology (Washington, D.C.) · 2025Review
- Iridescent biofilms of Cellulophaga lytica are tunable platforms for scalable, ordered materials.Scientific reports · 2023Article
- Interspecific hybridization explains rapid gorget colour divergence inRoyal Society open science · 2023Article
- Hummingbird plumage color diversity exceeds the known gamut of all other birds.Communications biology · 2022Article
- Feather iridescence ofBiology letters · 2021Article
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Authors and funding
3 authors.
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Abstract
The male Anna's hummingbird features a brightly reddish-pink reflecting gorget, due to large stacks of melanosomes in the feather barbules, arranged in layers separated by keratin. Direct observations together with detailed scatterometry demonstrated that the barbules reflect incident light in an approximately specular manner. The structural colouration is iridescent, i.e. varies with a changing angle of light incidence. Spectrophotometrical measurements of the barbule reflectance and absorbance can be well interpreted with calculated spectra obtained with a transfer matrix method for optical multilayers, using anatomical data and measured refractive index spectra. The organization of the reflectors as a Venetian blind presumably functions to create a high spectral contrast of the male's plumage during courtship.
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