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Sensory

Fish Vision

How fish see - often better than we do underwater, with color vision, UV sensitivity, and polarized light detection in many species.

System: Nervous Level: Intermediate Discipline: Physiology

📖 Overview

Fish eyes are optimized for water - a medium where the lens must do more optical work than in air. Round lenses focus light effectively; retinas often contain multiple cone types for color vision (some reef fish have 4-color vision, versus our 3). Many fish see UV light; some detect polarized light for navigation. Deep-sea fish often have tubular eyes to gather scarce light.

🔑 Key Concepts

Spherical lens, tapetum lucidum, tetrachromatic vision, UV vision, polarized light detection.

Fun Fact

Mantis shrimp - relatives of fish in the crustacean world - have 12 color receptor types compared to our 3. Some reef fish approach 4-5.