The image-forming mirror in the eye of the scallop

Fine-tuned for image formation We typically think of eyes as having one or more lenses for focusing incoming light onto a surface such as our retina. However, light can also be focused using arrays of mirrors, as is commonly done in telescopes. A biological example of this is the scallop, which can have up to 200 reflecting eyes that focus light onto two retinas. Palmer et al. find that spatial vision in the scallop is achieved through precise control of the size, shape, and packing density of the tiles of guanine that together make up an image-forming mirror at the back of each of the eyes. Science, this issue p. 1172 The crystal morphology, organization, and three-dimensional shape of the scallop eye mirror are finely controlled for image formation. Scallops possess a visual system comprising up to 200 eyes, each containing a concave mirror rather than a lens to focus light. The hierarchical organization of the multilayered mirror is controlled for image formation, from the component guanine crystals at the nanoscale to the complex three-dimensional morphology at the millimeter level. The layered structure of the mirror is tuned to reflect the wavelengths of light penetrating the scallop’s habitat and is tiled with a mosaic of square guanine crystals, which reduces optical aberrations. The mirror forms images on a double-layered retina used for separately imaging the peripheral and central fields of view. The tiled, off-axis mirror of the scallop eye bears a striking resemblance to the segmented mirrors of reflecting telescopes.

[1]  S. Weiner,et al.  Biologically Controlled Morphology and Twinning in Guanine Crystals. , 2017, Angewandte Chemie.

[2]  S. Weiner,et al.  Light Manipulation by Guanine Crystals in Organisms: Biogenic Scatterers, Mirrors, Multilayer Reflectors and Photonic Crystals , 2017 .

[3]  A. Oldenburg,et al.  Examining the Effects of Chromatic Aberration, Object Distance, and Eye Shape on Image-Formation in the Mirror-Based Eyes of the Bay Scallop Argopecten irradians , 2016, Integrative and comparative biology.

[4]  A. Steuwer,et al.  The Dual Function of Orchid Bee Ocelli as Revealed by X-Ray Microtomography , 2016, Current Biology.

[5]  S. Weiner,et al.  Light‐Induced Color Change in the Sapphirinid Copepods: Tunable Photonic Crystals , 2016 .

[6]  L. Addadi,et al.  “Guanigma”: The Revised Structure of Biogenic Anhydrous Guanine , 2015 .

[7]  J. Aizenberg,et al.  Multifunctionality of chiton biomineralized armor with an integrated visual system , 2015, Science.

[8]  S. Weiner,et al.  The mechanism of color change in the neon tetra fish: a light-induced tunable photonic crystal array. , 2015, Angewandte Chemie.

[9]  S. Weiner,et al.  Structural Basis for the Brilliant Colors of the Sapphirinid Copepods. , 2015, Journal of the American Chemical Society.

[10]  Curtis D Mobley,et al.  Inherent optical properties of Jerlov water types. , 2015, Applied optics.

[11]  M. Milinkovitch,et al.  Photonic crystals cause active colour change in chameleons , 2015, Nature Communications.

[12]  J. Partridge,et al.  Disordered animal multilayer reflectors and the localization of light , 2014, Journal of The Royal Society Interface.

[13]  S. Weiner,et al.  The structural basis for enhanced silver reflectance in Koi fish scale and skin. , 2014, Journal of the American Chemical Society.

[14]  N. J. Marshall,et al.  Reflecting optics in the diverticular eye of a deep-sea barreleye fish (Rhynchohyalus natalensis) , 2014, Proceedings of the Royal Society B: Biological Sciences.

[15]  J. Partridge,et al.  Non-polarizing broadband multilayer reflectors in fish , 2012, Nature Photonics.

[16]  Johannes E. Schindelin,et al.  Fiji: an open-source platform for biological-image analysis , 2012, Nature Methods.

[17]  S. Johnsen,et al.  Spectral sensitivity of the concave mirror eyes of scallops: potential influences of habitat, self-screening and longitudinal chromatic aberration , 2011, Journal of Experimental Biology.

[18]  S. Weiner,et al.  Guanine‐Based Biogenic Photonic‐Crystal Arrays in Fish and Spiders , 2010 .

[19]  R. Douglas,et al.  A Novel Vertebrate Eye Using Both Refractive and Reflective Optics , 2009, Current Biology.

[20]  S. Johnsen,et al.  Comparative Morphology of the Concave Mirror Eyes of Scallops (Pectinoidea)* , 2008 .

[21]  S. Johnsen,et al.  Scallops visually respond to the size and speed of virtual particles , 2008, Journal of Experimental Biology.

[22]  Steve Weiner,et al.  Biogenic Guanine Crystals from the Skin of Fish May Be Designed to Enhance Light Reflectance , 2008 .

[23]  Justin Marshall,et al.  Stomatopod eye structure and function: a review. , 2007, Arthropod structure & development.

[24]  Luke P. Lee,et al.  Biologically Inspired Artificial Compound Eyes , 2006, Science.

[25]  Eric J Warrant,et al.  Vision in the deep sea , 2004, Biological reviews of the Cambridge Philosophical Society.

[26]  Uwe Homberg,et al.  Ultrastructure and orientation of ommatidia in the dorsal rim area of the locust compound eye. , 2002, Arthropod structure & development.

[27]  Michinomae,et al.  STRUCTURAL BASIS FOR WAVELENGTH DISCRIMINATION IN THE BANKED RETINA OF THE FIREFLY SQUID WATASENIA SCINTILLANS , 1994, The Journal of experimental biology.

[28]  N. A. Locket,et al.  Possible Wavelength Discrimination by Multibank Retinae in Deep-Sea Fishes , 1989, Journal of the Marine Biological Association of the United Kingdom.

[29]  L. Wilkens,et al.  Neurobiology of the scallop. II: Structure of the parietovisceral ganglion lateral lobes in relation to afferent projections from the mantle eyes , 1983 .

[30]  D. Nilsson,et al.  Fine structure and optical properties of an ostracode (Crustacea) nauplius eye , 1981, Protoplasma.

[31]  M F Land,et al.  Mechanism of reflexion in silvery layers of fish and cephalopods , 1971, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[32]  A. Gorman,et al.  Photoreceptor Potentials of Opposite Polarity in the Eye of the Scallop, Pecten irradians , 1970, The Journal of general physiology.

[33]  M F Land,et al.  Movements of the retinae of jumping spiders (Salticidae: dendryphantinae) in response to visual stimuli. , 1969, The Journal of experimental biology.

[34]  Michael F. Land,et al.  A Multilayer Interference Reflector in the Eye of the Scallop, Pecten Maximus , 1966 .

[35]  M F Land,et al.  Activity in the optic nerve of Pecten maximus in response to changes in light intensity, and to pattern and movement in the optical environment. , 1966, The Journal of experimental biology.

[36]  J. Cronly-Dillon.  Spectral Sensitivity of the Scallop Pecten maximus , 1966, Science.

[37]  M. Land.  Image formation by a concave reflector in the eye of the scallop, Pecten maximus. , 1965, The Journal of physiology.

[38]  V. C. Barber,et al.  The fine structure of the eye of the mollusc Pecten maximus , 2004, Zeitschrift für Zellforschung und Mikroskopische Anatomie.