title: A highly conspicuous mineralized composite photonic architecture in the translucent shell of the blue-rayed limpet.
abstract: Many species rely on diverse selections of entirely organic photonic structures for the manipulation of light and the display of striking colours. Here we report the discovery of a mineralized hierarchical photonic architecture embedded within the translucent shell of the blue-rayed limpet Patella pellucida. The bright colour of the limpet's stripes originates from light interference in a periodically layered zig-zag architecture of crystallographically co-oriented calcite lamellae. Beneath the photonic multilayer, a disordered array of light-absorbing particles provides contrast for the blue colour. This unique mineralized manifestation of a synergy of two distinct optical elements at specific locations within the continuum of the limpet's translucent protective shell ensures the vivid shine of the blue stripes, which can be perceived under water from a wide range of viewing angles. The stripes' reflection band coincides with the spectral range of minimal light absorption in sea water, raising intriguing questions regarding their functional significance.
authors.affiliation: Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.affiliation: 1] Wyss Institute for Biologically Inspired Engineering, Harvard University, 60 Oxford Street, Cambridge, Massachusetts 02138, USA [2] School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kolle
authors.affiliation: Wyss Institute for Biologically Inspired Engineering, Harvard University, 60 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: James C
authors.initials: JC
authors.lastname: Weaver
authors.affiliation: Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Ortiz
authors.affiliation: 1] Wyss Institute for Biologically Inspired Engineering, Harvard University, 60 Oxford Street, Cambridge, Massachusetts 02138, USA [2] School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138, USA [3] Kavli Institute for Bionano Science and Technology at Harvard University, 29 Oxford Street, Cambridge, Massachusetts 02138, USA.
authors.forename: Joanna
authors.initials: J
authors.lastname: Aizenberg
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
authors.forename: Mathias
authors.initials: M
authors.lastname: Kolle
mesh_terms: D060105:Animal Shells / Q000648:ultrastructure*; D000818:Animals; D003116:Color; D049851:Gastropoda / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D055620:Optical Phenomena