Linked Life Data

15844175

Source:http://linkedlifedata.com/resource/pubmed/id/15844175

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2005-4-27
pubmed:abstractText
Subterranean mammals are generally considered to have reduced eyes and apparent blindness as a convergent adaptation to their lightless microhabitat. However, there are substantial interspecific differences. We have studied the prospect of vision in the Chilean subterranean rodent cururo (Spalacopus cyanus, Octodontidae) by analyzing the optical properties of the eye, the presence and distribution of rod and cone photoreceptors, and their spectral sensitivities. Cururo eye size is normal for rodents of similar body size, the cornea and lens are transparent from red to near-UV light, and the retina is well-structured. Electroretinography reveals three spectral mechanisms: a rod with peak sensitivity (lambda(max)) at about 500 nm, a cone with lambda(max) at about 505 nm (green-sensitive L-cone), and a cone with lambda(max) near 365 nm (UV-sensitive S-cone). This suggests dichromatic color vision. Immunocytochemistry with opsin-specific antibodies confirms the presence of rods, L-cones, and S-cones. Cururo rod density is much lower than that of nocturnal surface-dwelling rodents, and the cones form an unexpectedly high 10% proportion of the photoreceptors. Of these, S-cones constitute a regionally varying proportion from 2% in dorsal to 20% in ventral retina. The high cone proportion suggests adaptation to visual demands during the sporadic short phases of diurnal surface activity, rather than to the lightless subterranean environment. Our measurements on fresh cururo urine reveal a high UV reflectance, suggesting that scent marks may be visible to the UV-sensitive cones. The present results challenge the general view of convergent adaptive eye reduction and blindness in subterranean mammals.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9967
pubmed:author
pubmed:copyrightInfo
Copyright (c) 2005 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
6
pubmed:volume
486
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
197-208
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Eye and vision in the subterranean rodent cururo (Spalacopus cyanus, Octodontidae).
pubmed:affiliation
Max Planck Institute for Brain Research, D-60528 Frankfurt, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't