Aesthete (chiton)

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Aesthetes are visual organs in chitons. They are tiny 'eyes', too small to be seen unaided, embedded in the organism's shell.[1] They may act in unison to function as a large, dispersed, compound eye.[2] They are light sensing organs that are derived from the mantle of the organism. Some chitons also have larger lens-bearing eyes.[2]

The aesthetes are derived from mantle tissue which extend through holes in the shell (microscopic). Recent studies[citation needed] by ultrasound analysis of the aesthetes have shown that they do not function as an eye, but as an excretory organ secreting periostracum (a proteinaceous material covering and protecting the shell from abrasion). this layer is constantly worn away by waves and debris as a function of their rugged habitat, and must be continuously replaced to protect the shell.

References[edit]

  1. ^ Boyle, P. R. (1976). "The aesthetes of chitons". Cell and Tissue Research 172 (3): 379–388. doi:10.1007/BF00399520.  edit
  2. ^ a b Serb, J. M.; Eernisse, D. J. (2008). "Charting Evolution's Trajectory: Using Molluscan Eye Diversity to Understand Parallel and Convergent Evolution". Evolution Education and Outreach 1 (4): 439–447. doi:10.1007/s12052-008-0084-1.  edit