Phylogenetic Origins of the Visual and Olfactory Organs

  • Roger Jankowski


Cranial placodes (Holland and Holland 2001; Bassham and Postlethwait 2005) are specialized areas of the head ectoderm of vertebrate embryos that typically first become apparent as patches of thickened, columnar epithelial cells. Placodes, with the exceptions of the neurohypophyseal and lens placodes, are neurogenic, differentiating into neurons as well as other cell types. Placode-derived tissues make a significant contribution to the visual, olfactory, acoustico-lateralis, and gustatory systems of all living vertebrates.


Olfactory Epithelium Olfactory Organ Olfactory Placode Ventral Diencephalon Anterior Neural Plate 
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Copyright information

© Springer-Verlag France 2013

Authors and Affiliations

  • Roger Jankowski
    • 1
  1. 1.Faculté de Médecine Service ORL - CHUUniversité de LorraineNancyFrance

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