Eyes and vision Sperm whale

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like other toothed whales, sperm whale can retract eyes.


the sperm whale s eye not differ of other toothed whales except in size. largest among toothed whales, weighing 170 g. overall ellipsoid in shape, compressed along visual axis, measuring 7×7×3 cm. cornea elliptical , lens spherical. sclera hard , thick, 1 cm anteriorly , 3 cm posteriorly. there no ciliary muscles. choroid thick , contains fibrous tapetum lucidum. other toothed whales, sperm whale can retract , protrude eyes 2-cm-thick retractor muscle attached around eye @ equator.


according fristrup , harbison (2002),


sperm whales eyes afford vision , sensitivity light. conjectured sperm whales use vision hunt squid, either detecting silhouettes below or detecting bioluminescence. if sperm whales detect silhouettes, fristrup , harbison suggested hunt upside down, allowing them use forward parts of ventral visual fields binocular vision.








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