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Updated: Jul 14, 2026
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Deep Vascular Imaging in the Eye with Flow-Enhanced Ultrasound
Published on: October 4, 2021
Adaptive features of aquatic mammals' eye
Alla M Mass1, Alexander Ya Supin
1Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia. alla_mass@sevin.ru
Anatomical Record (Hoboken, N.J. : 2007)
|May 23, 2007
Summary
Aquatic mammals possess specialized eyes for clear underwater and aerial vision, adapting their vision through unique pupil shapes and retinal structures. This review details these adaptations across cetaceans, pinnipeds, sirenians, and sea otters.
Area of Science:
- Comparative anatomy
- Ophthalmology
- Marine biology
Background:
- Aquatic mammals navigate diverse environments, requiring sophisticated visual systems.
- Understanding eye adaptations is crucial for marine mammal biology.
Purpose of the Study:
- To review eye anatomy and adaptations in four aquatic mammal groups.
- To compare underwater and aerial vision specializations.
- To examine retinal morphology and ganglion cell distribution.
Main Methods:
- Review of existing literature on eye anatomy and optics.
- Analysis of retinal laminar morphology.
- Examination of ganglion cell distribution topography.
Main Results:
- Aquatic mammals achieve emmetropia underwater and adapt for aerial vision.
- Species-specific pupil shapes and optic tapeta regulate light.
- Retinas are rich in rods, with adaptations for low light.
- Ganglion cell distribution varies, with 1 or 2 best-vision areas.
Conclusions:
- Marine mammal vision is highly adapted for both aquatic and aerial environments.
- Specific anatomical and physiological features support dual-environment vision.
- Further research can illuminate evolutionary adaptations in marine mammal eyes.
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