title: Surprising characteristics of visual systems of invertebrates.
abstract: OBJECTIVE
  To communicate relevant and striking aspects about the visual system of some close invertebrates.
  
  
  METHODS
  Review of the related literature.
  
  
  RESULTS
  The capacity of snails to regenerate a complete eye, the benefit of the oval shape of the compound eye of many flying insects as a way of stabilising the image during flight, the potential advantages related to the extreme refractive error that characterises the ocelli of many insects, as well as the ability to detect polarised light as a navigation system, are some of the surprising capabilities present in the small invertebrate eyes that are described in this work.
  
  
  CONCLUSIONS
  The invertebrate eyes have capabilities and sensorial modalities that are not present in the human eye. The study of the eyes of these animals can help us to improve our understanding of our visual system, and inspire the development of optical devices.
authors.affiliation: Departamento de Oftalmología, Hospital Universitario del Henares, Coslada, Madrid, España; Universidad Francisco de Vitoria, Madrid, España. Electronic address: juliogazpeitia@gmail.com.
authors.forename: J
authors.initials: J
authors.lastname: González-Martín-Moro
authors.affiliation: Escuela de Óptica, Universidad Complutense de Madrid, Madrid, España.
authors.forename: J L
authors.initials: JL
authors.lastname: Hernández-Verdejo
authors.affiliation: Airbus military, Madrid, España.
authors.forename: A E
authors.initials: AE
authors.lastname: Jiménez-Gahete
mesh_terms: D000818:Animals; D005075:Biological Evolution; D054910:Compound Eye, Arthropod / Q000502:physiology / Q000648:ultrastructure; D060733:Electromagnetic Radiation; D005426:Flight, Animal; D007313:Insecta / Q000502:physiology; D007448:Invertebrates / Q000502:physiology*; D017956:Photoreceptor Cells, Invertebrate / Q000502:physiology; D011235:Predatory Behavior; D012029:Refraction, Ocular; D012038:Regeneration / Q000502:physiology; D012908:Snails / Q000502:physiology; D013045:Species Specificity; D013112:Spiders / Q000502:physiology; D014785:Vision, Ocular / Q000502:physiology*
keywords: Ametropía extrema; Compound eye; Extreme refractive error; Luz polarizada; Ocellus; Ocelo; Ocular regeneration; Ojo compuesto; Polarized light; Polifenismo; Polyphenism; Regeneración ocular; Tapetum lucidum