Publication
Title
Springtail coloration at a finer scale : mechanisms behind vibrant collembolan metallic colours
Author
Abstract
The mechanisms and evolution of metallic structural colours are of both fundamental and applied interest, yet most work in arthropods has focused on derived butterflies and beetles with distinct hues. In particular, basal hexapods-groups with many scaled, metallic representatives-are currently poorly studied and controversial, with some recent studies suggesting either that thin-film (lamina thickness) or diffraction grating (longitudinal ridges, cross-ribs) elements produce these colours in early Lepidoptera and one springtail (Collembola) species. Especially the collembolan basal scale design, consisting of a single lamina and longitudinal ridges with smooth valleys lacking cross-ribs, makes them an interesting group to explore the mechanisms of metallic coloration. Using microspectroscopy, Raman spectroscopy, electron microscopy and finite-difference time-domain optical modelling, we investigated scale colour in seven springtail species that show clear metallic coloration. Reflectance spectra are largely uniform and exhibit a broadband metallic/golden coloration with peaks in the violet/blue region. Our simulations confirm the role of the longitudinal ridges, working in conjunction with thin-film effects to produce a broadband metallic coloration. Broadband coloration occurs through spatial colour mixing, which probably results from nanoscale variation in scale thickness and ridge height and distance. These results provide crucial insights into the colour production mechanisms in a basal scale design and highlight the need for further investigation of scaled, basal arthropods.
Language
English
Source (journal)
Journal of the Royal Society interface: physical and life sciences. - London
Publication
London : 2021
ISSN
1742-5689
DOI
10.1098/RSIF.2021.0188
Volume/pages
18 :180 (2021) , 15 p.
Article Reference
20210188
ISI
000671880600001
Pubmed ID
34229459
Medium
E-only publicatie
Full text (Publisher's DOI)
UAntwerpen
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 30.07.2021
Last edited 02.10.2024
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