In Fish
All bony fishes, some sharks and rays have yolk sacs at some stage of development, with all oviparous fished retaining the sac after hatching. Lamniform sharks are ovoviviparous, in that their eggs hatch in utero, in addition to eating unfertilized eggs, unborn sharks participate in intrauterine-cannibalism: stronger pups consume their weaker womb-mates.
Read more about this topic: Yolk Sac
Famous quotes containing the word fish:
“Science, which cuts its way through the muddy pond of daily life without mingling with it, casts its wealth to right and left, but the puny boatmen do not know how to fish for it.”
—Alexander Herzen (1812–1870)
“Thou stately stream that with the swelling tide
‘Gainst London walls incessantly dost beat,
Thou Thames, I say, where barge and boat doth ride,
And snow-white swans do fish for needful meat:”
—George Turberville (1821–1873)