A Chiton Uses Aragonite Lenses to Form Images

@article{Speiser2011ACU,
  title={A Chiton Uses Aragonite Lenses to Form Images},
  author={D. I. Speiser and D. Eernisse and S. Johnsen},
  journal={Current Biology},
  year={2011},
  volume={21},
  pages={665-670}
}
Hundreds of ocelli are embedded in the dorsal shell plates of certain chitons. These ocelli each contain a pigment layer, retina, and lens, but it is unknown whether they provide chitons with spatial vision. It is also unclear whether chiton lenses are made from proteins, like nearly all biological lenses, or from some other material. Electron probe X-ray microanalysis and X-ray diffraction revealed that the chiton Acanthopleura granulata has the first aragonite lenses ever discovered. We found… Expand

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References

SHOWING 1-10 OF 54 REFERENCES
Structure and function of the larval eye of the sawfly, Perga.
TLDR
The visual properties of the stemmata of fourth and fifth instar sawfly larvae have been investigated by means of intracellular electrophysiological recordings, interference-, light-, scanning, and transmission electron microscopy, and ray tracing techniques and a system of highly oriented microvilli is thought to be responsible for the polarization sensitivity. Expand
Fine structure and optical properties of an ostracode (Crustacea) nauplius eye
TLDR
The investigated nauplius eye is the only one known with both a mirror and a highly refractive lens in the dioptric apparatus. Expand
Eyes as optical alarm systems in fan worms and ark clams
TLDR
The possibility that hyperpolarizing photoreceptor cells (shadow detectors) evolved from chemoreceptors that were inhibited by light is suggested. Expand
Image formation by a concave reflector in the eye of the scallop, Pecten maximus.
  • M. Land
  • Geology, Medicine
  • The Journal of physiology
  • 1965
TLDR
The eye of Pecten has been described histologically many times, but there has been no serious attempt to examine it as an optical system, nor to assess the nature and quality of the visual image that such an eye produces. Expand
Trilobite vision; a comparison of schizochroal and holochroal eyes with the compound eyes of modern arthropods
TLDR
Examination of holochroal compound eyes in Asaphus cornutus, Isotelus gigas, and Homote- lus sp. Expand
The spatial resolution of the pinhole eyes of giant clams (Tridacna maxima
  • M. Land
  • Physics, Medicine
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 2003
TLDR
Giant clams have several hundred small pinhole–type eyes on the exposed mantle and respond by withdrawing the mantle to movements of dark objects, even if these cast no shadow on the animal as a whole, which implies an acceptance angle for the best–resolving eyes of between 8.7° and 21.8°. Expand
Comparative Morphology of the Concave Mirror Eyes of Scallops (Pectinoidea)*
TLDR
It is hypothesized that scallop distal retinas may perform tasks of similar importance to all species, such as predator detection, and that proximal retinas might perform tasks more important to swimming species,such as those associated with the visual detection of preferred habitats. Expand
Fine structure of the eyes of Onithochiton neglectus (Mollusca: Polyplacophora)
  • P. Boyle
  • Biology, Medicine
  • Zeitschrift für Zellforschung und Mikroskopische Anatomie
  • 2004
TLDR
Onithochiton neglectus a common littoral chiton possesses large numbers of small eyes embedded in the outer layer of the shell, the tegmentum, which it is thought that the lamellate bodies are also sensory. Expand
Rhabdomeric Ocellus in a Chiton
TLDR
Electron microscopy of the aesthetes of several American species has failed to reveal any structures recognizable as typical of photoreceptors, and it is assumed that these shell organelles function as light receptors. Expand
Gereral purpose and special purpose visual systems
The information that eyes supply supports a wide variety of functions, from the guidance systems that enable an animal to navigate successfully around the environment, to the detection andExpand
...
1
2
3
4
5
...