Abstract
Sea otters are carnivorous, amphibious mammals that are active both above and under water. Accordingly, it might be expected that their eyes are adapted for both aerial and aqueous vision. We examined the anatomy and physiological optics of the sea otter eye with a view towards describing and explaining its amphibious visual characteristics. We employed photokeratoscopy to measure the refractive power of the sea otter cornea, which we found to be 59 D. Using video dynamic photorefraction, we found that sea otters can focus targets clearly both in air and water, relying on accommodation to compensate for the refractive loss of their corneas upon immersion in water. Our anatomical investigations revealed that the anterior epithelium of the cornea is extensively developed, as is the iris musculature, meridional ciliary muscle, and the corneoscleral venous plexus. The first feature is most likely an adaptation to the salinity of the marine environment. We believe the latter features are part of a novel, well-developed lenticular accommodative mechanism.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 23-32 |
| Number of pages | 10 |
| Journal | Vision Research |
| Volume | 30 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1990 |
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Keywords
- Accommodation
- Corneal curvature
- Enhydra lutris
- Optics
- Photokeratometry
- Photorefraction
- Refraction
- Sea otter
ASJC Scopus subject areas
- Ophthalmology
- Sensory Systems
Cite this
Refractive state, ocular anatomy, and accommodative range of the sea otter (Enhydra lutris). / Murphy, Christopher J; Bellhorn, Roy W.; Williams, Tom; Burns, Margaret S.; Schaeffel, Frank; Howland, Howard C.
In: Vision Research, Vol. 30, No. 1, 1990, p. 23-32.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Refractive state, ocular anatomy, and accommodative range of the sea otter (Enhydra lutris)
AU - Murphy, Christopher J
AU - Bellhorn, Roy W.
AU - Williams, Tom
AU - Burns, Margaret S.
AU - Schaeffel, Frank
AU - Howland, Howard C.
PY - 1990
Y1 - 1990
N2 - Sea otters are carnivorous, amphibious mammals that are active both above and under water. Accordingly, it might be expected that their eyes are adapted for both aerial and aqueous vision. We examined the anatomy and physiological optics of the sea otter eye with a view towards describing and explaining its amphibious visual characteristics. We employed photokeratoscopy to measure the refractive power of the sea otter cornea, which we found to be 59 D. Using video dynamic photorefraction, we found that sea otters can focus targets clearly both in air and water, relying on accommodation to compensate for the refractive loss of their corneas upon immersion in water. Our anatomical investigations revealed that the anterior epithelium of the cornea is extensively developed, as is the iris musculature, meridional ciliary muscle, and the corneoscleral venous plexus. The first feature is most likely an adaptation to the salinity of the marine environment. We believe the latter features are part of a novel, well-developed lenticular accommodative mechanism.
AB - Sea otters are carnivorous, amphibious mammals that are active both above and under water. Accordingly, it might be expected that their eyes are adapted for both aerial and aqueous vision. We examined the anatomy and physiological optics of the sea otter eye with a view towards describing and explaining its amphibious visual characteristics. We employed photokeratoscopy to measure the refractive power of the sea otter cornea, which we found to be 59 D. Using video dynamic photorefraction, we found that sea otters can focus targets clearly both in air and water, relying on accommodation to compensate for the refractive loss of their corneas upon immersion in water. Our anatomical investigations revealed that the anterior epithelium of the cornea is extensively developed, as is the iris musculature, meridional ciliary muscle, and the corneoscleral venous plexus. The first feature is most likely an adaptation to the salinity of the marine environment. We believe the latter features are part of a novel, well-developed lenticular accommodative mechanism.
KW - Accommodation
KW - Corneal curvature
KW - Enhydra lutris
KW - Optics
KW - Photokeratometry
KW - Photorefraction
KW - Refraction
KW - Sea otter
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UR - http://www.scopus.com/inward/citedby.url?scp=0025129265&partnerID=8YFLogxK
U2 - 10.1016/0042-6989(90)90125-5
DO - 10.1016/0042-6989(90)90125-5
M3 - Article
C2 - 2321364
AN - SCOPUS:0025129265
VL - 30
SP - 23
EP - 32
JO - Vision Research
JF - Vision Research
SN - 0042-6989
IS - 1
ER -